JP5114106B2 - Voice input / output device and communication device - Google Patents

Abstract

The invention provides an input and output device and a talking device, which can provide a comfortable talking environment that can suffer little from the ambient noises, impacting sounds, echoes and screaming sounds. The voice input-output device includes a voice input section and a voice output section. The voice input section includes a microphone unit, the microphone unit including a housing that has an inner space, a partition member that is provided in the housing and divides the inner space into a first space and a second space, the partition member being at least partially formed of a diaphragm, and an electrical signal output circuit that outputs an electrical signal that is the first voice signal based on vibrations of the diaphragm, a first through-hole through which the first space communicates with an outer space of the housing and a second through-hole through which the second space communicates with the outer space being formed in the housing. The voice output section includes: an ambient noise detection section that detects ambient noise during a call based on the first voice signal; and a volume control section that controls volume of the speaker based on a degree of the detected ambient noise.

Description

  The present invention relates to a voice input / output device and a communication device.

  In a telephone call, voice recognition, voice recording, etc., it is preferable to pick up only the target voice (user voice). However, in a usage environment of the voice input device, there may be a sound other than the target voice such as background noise. Therefore, development of a voice input device having a function of removing noise has been advanced.

  As a technology to remove noise in a usage environment where noise exists, the microphone has a sharp directivity, or the arrival direction of the sound wave is identified using the difference in arrival time of the sound wave, and the noise is removed by signal processing. The method is known.

In recent years, electronic devices have been downsized, and technology for downsizing a voice input device has become important.
JP 7-312638 A Japanese Patent Laid-Open No. 9-331377 JP 2001-186241 A

  In order to give the microphone a sharp directivity, it is necessary to arrange a large number of vibrating membranes, and miniaturization is difficult.

  In addition, in order to accurately detect the direction of arrival of sound waves using the difference in arrival times of sound waves, it is necessary to install a plurality of vibrating membranes at intervals of about one-several wavelengths of audible sound waves. Is difficult.

  In addition, when a voice input / output device such as a telephone, a mobile phone, or a headset microphone / speaker unit is used in a noisy environment, it is generally difficult to clearly hear the voice of the other party.

  An object of the present invention is to provide a voice input / output device and a call device that can provide a comfortable call environment with less influence of ambient noise, impact sound, echo, howling, and the like.

(1) The present invention
An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A housing having an internal space, a partition member provided in the housing, which divides the internal space into a first space and a second space, at least a part of which is made of a vibrating membrane; and the vibration An electrical signal output circuit that outputs an electrical signal that is a first audio signal based on vibrations of the membrane, and the housing communicates with the first space and an external space of the housing. A microphone unit in which a through-hole of 1 and a second through-hole communicating with the second space and the external space of the housing are formed is mounted;
The audio output unit
An ambient noise detector for detecting ambient noise during a call based on the first audio signal;
And a volume control unit that controls the volume of the speaker based on the magnitude of the detected ambient noise.

  The ambient noise during a call may be determined by, for example, an electrical signal (sound pressure, for example, a voltage detected by a microphone) detected at the start of the call. In general, voice exchange starts after standing for about 1 second, not immediately after the call can be started, so that the electrical signal detected immediately after the start of the call is regarded as ambient noise and controls the output volume. You may do it.

  Also, based on the transition of the electrical signal during a call, it is determined whether there is a voice input section or no voice input section, and the electrical signal detected in the voice input no section is regarded as ambient noise and the output volume is controlled. May be.

  The voice input / output device may be a telephone, a mobile phone or other telephone communication device, or a headset microphone / speaker unit, a musical sound playback device (karaoke set) having a microphone and a speaker, a TV having a microphone and a speaker, A radio or personal computer may be used.

  The loudspeaker volume may be controlled to change continuously or stepwise based on the magnitude of the detected ambient noise.

  According to the present invention, user voice and noise are incident on both sides of the diaphragm. Of the sound incident on both sides of the diaphragm, the noise component has almost the same sound pressure, and therefore cancels with the diaphragm. Therefore, the sound pressure that vibrates the diaphragm can be regarded as the sound pressure indicating the user voice, and the electric signal acquired based on the vibration of the diaphragm is an electric signal indicating the user voice from which noise has been removed. It can be considered as a signal.

  Therefore, according to the present invention, it is possible to provide a high-quality microphone unit capable of deep noise removal with a simple configuration.

  When such a voice input / output device or the like is used in a noisy environment, it is difficult to clearly hear the second voice signal (for example, the voice of the other party), but according to the present invention, the microphone unit for voice input is used, By controlling the volume of the speaker continuously or stepwise according to the intensity of the ambient noise obtained from the microphone unit, it is easy for the voice input person to hear the sound output from the speaker. It is possible to provide a voice / voice input / output device that facilitates transmission and reception.

(2) The present invention
An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A first vibrating membrane constituting a first microphone, a second vibrating membrane constituting a second microphone, a first voltage signal acquired by the first microphone, and a second microphone; A semiconductor substrate formed with a difference signal generation circuit that receives the acquired second voltage signal and generates a first audio signal based on a difference signal indicating a difference between the first and second voltage signals An integrated circuit device is mounted,
The audio output unit
An ambient noise detector for detecting ambient noise during a call based on the first audio signal;
And a volume control unit that controls the volume of the speaker based on the magnitude of the detected ambient noise.

  The ambient noise during a call may be determined by, for example, an electrical signal (sound pressure, for example, a voltage detected by a microphone) detected at the start of the call. In general, voice exchange starts after standing for about 1 second, not immediately after the call can be started, so that the electrical signal detected immediately after the start of the call is regarded as ambient noise and controls the output volume. You may do it.

  Also, based on the transition of the electrical signal during a call, it is determined whether there is a voice input section or no voice input section, and the electrical signal detected in the voice input no section is regarded as ambient noise and the output volume is controlled. May be.

  The voice input / output device may be a telephone, a mobile phone or other telephone communication device, or a headset microphone / speaker unit, a musical sound playback device (karaoke set) having a microphone and a speaker, a TV having a microphone and a speaker, A radio or personal computer may be used.

  The loudspeaker volume may be controlled to change continuously or stepwise based on the magnitude of the detected ambient noise.

  According to the present invention, it is possible to generate a signal indicating a sound from which a noise component has been removed by a simple process that only generates a difference signal indicating a difference between two voltage signals. According to the present invention, since the first and second vibrating membranes and the differential signal generation circuit 30 are formed on one semiconductor substrate, the external shape of the integrated circuit device can be reduced, and the integrated circuit The accuracy of the apparatus can be increased.

  Thus, according to the present invention, it is possible to provide an integrated circuit device that has a small outer shape and can realize a highly accurate noise removal function.

  Note that the integrated circuit device can be applied as a voice input element (microphone element) of a close-talking voice input device. At this time, in the integrated circuit device, the first and second vibrating membranes have an intensity of the noise component included in the difference signal with respect to an intensity of the noise component included in the first or second voltage signal. The noise intensity ratio indicating the ratio is smaller than the audio intensity ratio indicating the ratio of the intensity of the input audio component included in the difference signal to the intensity of the input audio component included in the first or second voltage signal. It may be arranged as follows. At this time, the noise intensity ratio may be an intensity ratio based on the phase difference component of noise, and the voice intensity ratio may be an intensity ratio based on the amplitude component of the input voice.

  The integrated circuit device (semiconductor substrate) may be configured as a so-called MEMS (Micro Electro Mechanical Systems).

  When such a voice input / output device or the like is used in a noisy environment, it is difficult to clearly hear the second voice signal (for example, the voice of the other party), but according to the present invention, the microphone unit for voice input is used, By controlling the volume of the speaker continuously or stepwise according to the intensity of the ambient noise obtained from the microphone unit, it is easy for the voice input person to hear the sound output from the speaker. It is possible to provide a voice / voice input / output device that facilitates transmission and reception.

(3) The present invention
An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A first microphone having a first vibrating membrane;
A second microphone having a second vibrating membrane;
Difference signal generation for generating a first audio signal based on a difference signal indicating a difference between a first voltage signal acquired by the first microphone and a second voltage signal acquired by the second microphone And
The first and second diaphragms have a noise intensity ratio indicating a ratio of the intensity of the noise component included in the differential signal to the intensity of the noise component included in the first or second voltage signal. Arranged so as to be smaller than the input voice intensity ratio indicating the ratio of the intensity of the input voice component included in the difference signal to the intensity of the input voice component included in the first or second voltage signal;
The audio output unit
An ambient noise detector for detecting ambient noise during a call based on the first audio signal;
And a volume control unit that controls the volume of the speaker based on the magnitude of the detected ambient noise.

  The ambient noise during a call may be determined by, for example, an electrical signal (sound pressure, for example, a voltage detected by a microphone) detected at the start of the call. In general, voice exchange starts after standing for about 1 second, not immediately after the call can be started, so that the electrical signal detected immediately after the start of the call is regarded as ambient noise and controls the output volume. You may do it.

  Also, based on the transition of the electrical signal during a call, it is determined whether there is a voice input section or no voice input section, and the electrical signal detected in the voice input no section is regarded as ambient noise and the output volume is controlled. May be.

  The voice input / output device may be a telephone, a mobile phone or other telephone communication device, or a headset microphone / speaker unit, a musical sound playback device (karaoke set) having a microphone and a speaker, a TV having a microphone and a speaker, A radio or personal computer may be used.

  The loudspeaker volume may be controlled to change continuously or stepwise based on the magnitude of the detected ambient noise.

  According to the present invention, the first and second microphones (first and second vibrating membranes) are arranged so as to satisfy a predetermined condition. According to this, the difference signal indicating the difference between the first and second voltage signals acquired by the first and second microphones can be regarded as a signal indicating the input sound from which the noise component has been removed. Therefore, according to the present invention, it is possible to provide a voice input device capable of realizing a noise removal function with a simple configuration that only generates a differential signal.

  In the voice input / output device of the present invention, the difference signal generation unit generates a difference signal without performing analysis processing (Fourier analysis processing or the like) on the first and second voltage signals. Therefore, it is possible to reduce the signal processing load of the differential signal generation unit, or to realize the differential signal generation unit with a very simple circuit.

  Therefore, according to the present invention, it is possible to provide a voice input device that can be miniaturized and can realize a highly accurate noise removal function.

  In this voice input device, the first and second diaphragms may be arranged such that the intensity ratio based on the phase difference component of the noise component is smaller than the intensity ratio based on the amplitude of the input voice component. Good.

  When such a voice input / output device or the like is used in a noisy environment, it is difficult to clearly hear the second voice signal (for example, the voice of the other party), but according to the present invention, the microphone unit for voice input is used, By controlling the volume of the speaker continuously or stepwise according to the intensity of the ambient noise obtained from the microphone unit, it is easy for the voice input person to hear the sound output from the speaker. It is possible to provide a voice / voice input / output device that facilitates transmission and reception.

(4) The present invention
A hands-free type audio input unit that generates a first audio signal based on an input from a microphone;
A hands-free type voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A housing having an internal space, a partition member provided in the housing, which divides the internal space into a first space and a second space, at least a part of which is made of a vibrating membrane; and the vibration An electrical signal output circuit that outputs an electrical signal that is a first audio signal based on vibrations of the membrane, and the housing communicates with the first space and an external space of the housing. A microphone unit in which one through hole and a second through hole that communicates the second space and the external space of the housing are formed is mounted.

  A hands-free voice input unit refers to a voice input unit that allows a voice input person to input voice without gripping the voice input unit. The voice input unit is installed on a table or a wall, for example, For example, a hands-free mobile phone installed in an automobile or a hands-free loudspeaker used in a video conference or the like is also applicable.

  According to the present invention, user voice and noise are incident on both sides of the diaphragm. Of the sound incident on both sides of the diaphragm, the noise component has almost the same sound pressure, and therefore cancels with the diaphragm. Therefore, the sound pressure that vibrates the diaphragm can be regarded as the sound pressure indicating the user voice, and the electric signal acquired based on the vibration of the diaphragm is an electric signal indicating the user voice from which noise has been removed. It can be considered as a signal.

  Therefore, according to the present invention, it is possible to provide a high-quality microphone unit capable of deep noise removal with a simple configuration.

  In addition, the microphone unit has a characteristic of easily and extremely effectively suppressing the impact sound that acts directly or indirectly on the device. That is, not only the sound propagating in the air but also the sound propagating in the solid can be removed. Since the propagation speed of sound in solids is extremely fast (about 10 times) compared to the propagation speed in air, the impact sound (noise) applied to the solid on which the microphone unit is installed reaches the vibrating membrane almost simultaneously. Therefore, it can be removed in the same way as noise propagating in the air.

  Further, since it is excellent in the performance of suppressing howling generated between the microphone and the speaker, it is possible to provide a high-performance hands-free loudspeaker device by incorporating it in a hands-free telephone set on a table, for example.

  Therefore, according to the present invention, it is excellent in noise suppression performance against impact noise directly or indirectly acting on a microphone. Therefore, by incorporating it in a hands-free type voice input / output device, it has been extremely uncomfortable and can be removed. It is possible to provide a device with excellent performance even under impact noise that has been difficult.

  The same effect can be obtained by incorporating it into a keyboard of a personal computer, a working robot, a digital recorder, a hearing aid, or the like.

(5) The present invention
A hands-free type audio input unit that generates a first audio signal based on an input from a microphone;
A hands-free type voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A first vibrating membrane constituting a first microphone, a second vibrating membrane constituting a second microphone, a first voltage signal acquired by the first microphone, and a second microphone; A semiconductor substrate formed with a difference signal generation circuit that receives the acquired second voltage signal and generates a first audio signal based on a difference signal indicating a difference between the first and second voltage signals An integrated circuit device having the above is mounted.

  A hands-free voice input unit refers to a voice input unit that allows a voice input person to input voice without gripping the voice input unit. The voice input unit is installed on a table or a wall, for example, For example, a hands-free mobile phone installed in an automobile, a hands-free loudspeaker used in a TV conference, or the like, which is used to pick up voice, also corresponds to the right.

  According to the present invention, it is possible to generate a signal indicating a sound from which a noise component has been removed by a simple process that only generates a difference signal indicating a difference between two voltage signals. According to the present invention, since the first and second vibrating membranes and the differential signal generation circuit 30 are formed on one semiconductor substrate, the external shape of the integrated circuit device can be reduced, and the integrated circuit The accuracy of the apparatus can be increased.

  Thus, according to the present invention, it is possible to provide an integrated circuit device that has a small outer shape and can realize a highly accurate noise removal function.

  Note that the integrated circuit device can be applied as a voice input element (microphone element) of a close-talking voice input device. At this time, in the integrated circuit device, the first and second vibrating membranes have an intensity of the noise component included in the difference signal with respect to an intensity of the noise component included in the first or second voltage signal. The noise intensity ratio indicating the ratio is smaller than the audio intensity ratio indicating the ratio of the intensity of the input audio component included in the difference signal to the intensity of the input audio component included in the first or second voltage signal. It may be arranged as follows. At this time, the noise intensity ratio may be an intensity ratio based on the phase difference component of noise, and the voice intensity ratio may be an intensity ratio based on the amplitude component of the input voice.

  The integrated circuit device (semiconductor substrate) may be configured as a so-called MEMS (Micro Electro Mechanical Systems).

  In addition, the microphone unit has a characteristic of easily and extremely effectively suppressing the impact sound that acts directly or indirectly on the device. That is, not only the sound propagating in the air but also the sound propagating in the solid can be removed. Since the propagation speed of sound in a solid is extremely high (about 10 times) compared to the propagation speed in air, the impact sound (noise) applied to the solid on which the microphone unit is installed is almost simultaneously Since it reaches the vibration film 2, it can be removed in the same manner as noise that propagates in the air.

  Further, since it is excellent in the performance of suppressing howling generated between the microphone and the speaker, it is possible to provide a high-performance hands-free loudspeaker device by incorporating it in a hands-free telephone set on a table, for example.

  Therefore, according to the present invention, it is excellent in noise suppression performance against impact noise directly or indirectly acting on a microphone. Therefore, by incorporating it in a hands-free type voice input / output device, it has been extremely uncomfortable and can be removed. It is possible to provide a device with excellent performance even under impact noise that has been difficult.

  The same effect can be obtained by incorporating it into a keyboard of a personal computer, a working robot, a digital recorder, a hearing aid, or the like.

(6) The present invention
A hands-free type audio input unit that generates a first audio signal based on an input from a microphone;
A hands-free type voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A first microphone having a first vibrating membrane;
A second microphone having a second vibrating membrane;
Difference signal generation for generating a first audio signal based on a difference signal indicating a difference between a first voltage signal acquired by the first microphone and a second voltage signal acquired by the second microphone And
The first and second diaphragms have a noise intensity ratio indicating a ratio of the intensity of the noise component included in the differential signal to the intensity of the noise component included in the first or second voltage signal. The input voice component included in the difference signal is disposed so as to be smaller than an input voice intensity ratio indicating a ratio of the intensity of the input voice component included in the first or second voltage signal to the intensity of the input voice component. Features.

  A hands-free voice input unit refers to a voice input unit that allows a voice input person to input voice without gripping the voice input unit. The voice input unit is installed on a table or a wall, for example, For example, a hands-free mobile phone installed in an automobile, a hands-free loudspeaker used in a TV conference, or the like, which is used to pick up voice, also corresponds to the right.

  According to the present invention, the first and second microphones (first and second vibrating membranes) are arranged so as to satisfy a predetermined condition. According to this, the difference signal indicating the difference between the first and second voltage signals acquired by the first and second microphones can be regarded as a signal indicating the input sound from which the noise component has been removed. Therefore, according to the present invention, it is possible to provide a voice input device capable of realizing a noise removal function with a simple configuration that only generates a differential signal.

  In the voice input / output device of the present invention, the difference signal generation unit generates a difference signal without performing analysis processing (Fourier analysis processing or the like) on the first and second voltage signals. Therefore, it is possible to reduce the signal processing load of the differential signal generation unit, or to realize the differential signal generation unit with a very simple circuit.

  Therefore, according to the present invention, it is possible to provide a voice input device that can be miniaturized and can realize a highly accurate noise removal function.

  In this voice input device, the first and second diaphragms may be arranged such that the intensity ratio based on the phase difference component of the noise component is smaller than the intensity ratio based on the amplitude of the input voice component. Good.

  In addition, the microphone unit has a characteristic of easily and extremely effectively suppressing the impact sound that acts directly or indirectly on the device. That is, not only the sound propagating in the air but also the sound propagating in the solid can be removed. Since the propagation speed of sound in a solid is extremely high (about 10 times) compared to the propagation speed in air, the impact sound (noise) applied to the solid on which the microphone unit is installed is almost simultaneously Since it reaches the vibration film 2, it can be removed in the same manner as noise that propagates in the air.

  Further, since it is excellent in the performance of suppressing howling generated between the microphone and the speaker, it is possible to provide a high-performance hands-free loudspeaker device by incorporating it in a hands-free telephone set on a table, for example.

  Therefore, according to the present invention, it is excellent in noise suppression performance against impact noise directly or indirectly acting on a microphone. Therefore, by incorporating it in a hands-free type voice input / output device, it has been extremely uncomfortable and can be removed. It is possible to provide a device with excellent performance even under impact noise that has been difficult.

  The same effect can be obtained by incorporating it into a keyboard of a personal computer, a working robot, a digital recorder, a hearing aid, or the like.

(7) The present invention
An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A housing having an internal space, a partition member provided in the housing, which divides the internal space into a first space and a second space, at least a part of which is made of a vibrating membrane; and the vibration An electrical signal output circuit that outputs an electrical signal that is a first audio signal based on vibrations of the membrane, and the housing communicates with the first space and an external space of the housing. A microphone unit in which a through-hole of 1 and a second through-hole communicating with the second space and the external space of the housing are formed is mounted;
The voice output unit and the voice input unit are installed separately.

  The audio output unit and the audio input unit are installed separately from each other. For example, the audio output unit using the microphone unit of the present invention incorporated in a portable device, a remote controller, or the like, and a speaker such as a television set are used for output. It includes a configuration in which the voice receiving unit of the other party is paired and separated.

  According to the present invention, user voice and noise are incident on both sides of the diaphragm. Of the sound incident on both sides of the diaphragm, the noise component has almost the same sound pressure, and therefore cancels with the diaphragm. Therefore, the sound pressure that vibrates the diaphragm can be regarded as the sound pressure indicating the user voice, and the electric signal acquired based on the vibration of the diaphragm is an electric signal indicating the user voice from which noise has been removed. It can be considered as a signal.

  Therefore, according to the present invention, it is possible to provide a high-quality microphone unit capable of deep noise removal with a simple configuration.

  In addition, since it is excellent in the howling suppression performance generated between the microphone and the speaker, it is possible to provide a new voice input / output device resistant to a noise environment.

(8) The present invention
An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A first vibrating membrane constituting a first microphone, a second vibrating membrane constituting a second microphone, a first voltage signal acquired by the first microphone, and a second microphone; A semiconductor substrate formed with a difference signal generation circuit that receives the acquired second voltage signal and generates a first audio signal based on a difference signal indicating a difference between the first and second voltage signals An integrated circuit device is mounted,
The voice output unit and the voice input unit are installed separately.

  The audio output unit and the audio input unit are installed separately from each other. For example, the audio output unit using the microphone unit of the present invention incorporated in a portable device, a remote controller, or the like, and a speaker such as a television set are used for output. It includes a configuration in which the voice receiving unit of the other party is paired and separated.

  According to the present invention, it is possible to generate a signal indicating a sound from which a noise component has been removed by a simple process that only generates a difference signal indicating a difference between two voltage signals. According to the present invention, since the first and second vibrating membranes and the differential signal generation circuit 30 are formed on one semiconductor substrate, the external shape of the integrated circuit device can be reduced, and the integrated circuit The accuracy of the apparatus can be increased.

  Thus, according to the present invention, it is possible to provide an integrated circuit device that has a small outer shape and can realize a highly accurate noise removal function.

  Note that the integrated circuit device can be applied as a voice input element (microphone element) of a close-talking voice input device. At this time, in the integrated circuit device, the first and second vibrating membranes have an intensity of the noise component included in the difference signal with respect to an intensity of the noise component included in the first or second voltage signal. The noise intensity ratio indicating the ratio is smaller than the audio intensity ratio indicating the ratio of the intensity of the input audio component included in the difference signal to the intensity of the input audio component included in the first or second voltage signal. It may be arranged as follows. At this time, the noise intensity ratio may be an intensity ratio based on the phase difference component of noise, and the voice intensity ratio may be an intensity ratio based on the amplitude component of the input voice.

  The integrated circuit device (semiconductor substrate) may be configured as a so-called MEMS (Micro Electro Mechanical Systems).

  In addition, since it is excellent in the howling suppression performance generated between the microphone and the speaker, it is possible to provide a new voice input / output device resistant to a noise environment.

(9) The present invention
An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A first microphone having a first vibrating membrane;
A second microphone having a second vibrating membrane;
Difference signal generation for generating a first audio signal based on a difference signal indicating a difference between a first voltage signal acquired by the first microphone and a second voltage signal acquired by the second microphone And
The first and second diaphragms have a noise intensity ratio indicating a ratio of the intensity of the noise component included in the differential signal to the intensity of the noise component included in the first or second voltage signal. Arranged so as to be smaller than the input voice intensity ratio indicating the ratio of the intensity of the input voice component included in the difference signal to the intensity of the input voice component included in the first or second voltage signal;
The voice output unit and the voice input unit are installed separately.

  The audio output unit and the audio input unit are installed separately from each other. For example, the audio output unit using the microphone unit of the present invention incorporated in a portable device, a remote controller, or the like, and a speaker such as a television set are used for output. It includes a configuration in which the voice receiving unit of the other party is paired and separated.

  According to the present invention, the first and second microphones (first and second vibrating membranes) are arranged so as to satisfy a predetermined condition. According to this, the difference signal indicating the difference between the first and second voltage signals acquired by the first and second microphones can be regarded as a signal indicating the input sound from which the noise component has been removed. Therefore, according to the present invention, it is possible to provide a voice input device capable of realizing a noise removal function with a simple configuration that only generates a differential signal.

  In the voice input / output device of the present invention, the difference signal generation unit generates a difference signal without performing analysis processing (Fourier analysis processing or the like) on the first and second voltage signals. Therefore, it is possible to reduce the signal processing load of the differential signal generation unit, or to realize the differential signal generation unit with a very simple circuit.

  Therefore, according to the present invention, it is possible to provide a voice input device that can be miniaturized and can realize a highly accurate noise removal function.

  In this voice input device, the first and second diaphragms may be arranged such that the intensity ratio based on the phase difference component of the noise component is smaller than the intensity ratio based on the amplitude of the input voice component. Good.

  In addition, since it is excellent in the howling suppression performance generated between the microphone and the speaker, it is possible to provide a new voice input / output device resistant to a noise environment.

(10) The present invention
A voice input / output device according to any one of the above;
A transmission unit for transmitting the first audio signal generated by the audio input unit to the device of the other party;
And a receiving unit that receives a second audio signal transmitted from the device of the other party.

  Embodiments to which the present invention is applied will be described below with reference to the drawings. However, the present invention is not limited to the following embodiments. Moreover, this invention shall include what combined the following content freely.

1-1. Configuration of Microphone Unit 1 First, the configuration of the microphone unit 1 according to the present embodiment will be described.

  The microphone unit 1 according to the present embodiment includes a housing 10 as shown in FIGS. 1 and 2A. The housing 10 is a member that forms the outer shape of the microphone unit 1. The outer shape of the housing 10 (microphone unit 1) may have a polyhedral structure. The outer shape of the housing 10 may be a hexahedron (a cuboid or a cube) as shown in FIG. However, the outer shape of the housing 10 may have a polyhedral structure other than a hexahedron. Or the external shape of the housing | casing 10 may be structures other than a polyhedron, such as a spherical structure (hemispherical structure).

  As shown in FIG. 2A, the housing 10 has an internal space 100 (first and second spaces 102 and 104). That is, the housing 10 has a structure that partitions a predetermined space, and the internal space 100 is a space partitioned by the housing 10. The housing 10 may have a shielding structure (electromagnetic shield structure) that electrically and magnetically shields the internal space 100 and a space outside the housing 10 (external space 110). As a result, the diaphragm 30 and the electric signal output circuit 40 described later can be made less susceptible to the influence of electronic components arranged outside the housing 10 (external space 110). A microphone unit that can be realized can be provided.

  As shown in FIGS. 1 and 2A, the housing 10 is formed with a through hole that allows the internal space 100 and the external space 110 of the housing 10 to communicate with each other. In the present embodiment, the housing 10 is formed with a first through hole 12 and a second through hole 14. Here, the first through hole 12 is a through hole that communicates the first space 102 and the external space 110. The second through hole 14 is a through hole that communicates the second space 104 and the external space 110. The first and second spaces 102 and 104 will be described in detail later. Although the external shape of the 1st and 2nd through-holes 12 and 14 is not specifically limited, For example, as shown in FIG. 1, you may be circular. However, the outer shape of the first and second through holes 12 and 14 may be a shape other than a circle, for example, a rectangle.

  In the present embodiment, as shown in FIGS. 1 and 2A, the first and second through holes 12 and 14 are formed on one surface 15 of the housing 10 having a hexahedral structure (polyhedral structure). Has been. However, as a modification, the first and second through holes 12 and 14 may be formed on different surfaces of the polyhedron, respectively. For example, the first and second through holes 12 and 14 may be formed on opposing surfaces of the hexahedron, or may be formed on adjacent surfaces of the hexahedron. In the present embodiment, the housing 10 is formed with one first through hole 12 and one second through hole 14. However, the present invention is not limited to this, and the housing 10 may be formed with a plurality of first through holes 12 and a plurality of second through holes 14.

  The microphone unit 1 according to the present embodiment includes a partition member 20 as shown in FIGS. 2 (A) and 2 (B). Here, FIG. 2B is a view of the partition member 20 observed from the front. The partition member 20 is provided in the housing 10 so as to divide the internal space 100. In the present embodiment, the partition member 20 is provided so as to divide the internal space 100 into a first space 102 and a second space 104. That is, it can be said that the first and second spaces 102 and 104 are spaces defined by the housing 10 and the partition member 20, respectively.

  The partition member 20 may be provided so that the medium that propagates the sound wave does not move between the first space 102 and the second space 104 inside the housing 10 (so that the medium cannot move). . For example, the partition member 20 may be an airtight partition that airtightly separates the internal space 100 (the first and second spaces 102 and 104) inside the housing 10.

  As shown in FIGS. 2A and 2B, at least a part of the partition member 20 is composed of a vibration film 30. The vibration film 30 is a member that vibrates in the normal direction when a sound wave enters. In the microphone unit 1, an electrical signal indicating the sound incident on the diaphragm 30 is acquired by extracting an electrical signal based on the vibration of the diaphragm 30. That is, the vibration film 30 may be a vibration film of a microphone (an electroacoustic transducer that converts an acoustic signal into an electric signal).

  Hereinafter, a configuration of a condenser microphone 200 will be described as an example of a microphone applicable to the present embodiment. FIG. 3 is a diagram for explaining the condenser microphone 200.

  The condenser microphone 200 has a vibration film 202. The vibration film 202 corresponds to the vibration film 30 of the microphone unit 1 according to the present embodiment. The vibration film 202 is a film (thin film) that vibrates in response to sound waves, has conductivity, and forms one end of the electrode. The condenser microphone 200 also has an electrode 204. The electrode 204 is disposed to face the vibration film 202. Thereby, the vibrating membrane 202 and the electrode 204 form a capacitance. When a sound wave enters the condenser microphone 200, the vibration film 202 vibrates, the distance between the vibration film 202 and the electrode 204 changes, and the capacitance between the vibration film 202 and the electrode 204 changes. By taking out this change in capacitance as, for example, a change in voltage, an electrical signal based on the vibration of the vibration film 202 can be acquired. That is, the sound wave incident on the condenser microphone 200 can be converted into an electric signal and output. In the condenser microphone 200, the electrode 204 may have a structure that is not affected by sound waves. For example, the electrode 204 may have a mesh structure.

  However, the microphone (vibration membrane 30) applicable to the present invention is not limited to the condenser microphone, and any microphone that is already known can be applied. For example, the vibration film 30 may be a vibration film of various microphones such as an electrodynamic type (dynamic type), an electromagnetic type (magnetic type), and a piezoelectric type (crystal type).

  Alternatively, the vibration film 30 may be a semiconductor film (for example, a silicon film). That is, the vibration film 30 may be a vibration film of a silicon microphone (Si microphone). By using the silicon microphone, the microphone unit 1 can be reduced in size and performance can be improved.

  The outer shape of the vibration film 30 is not particularly limited. As shown in FIG. 2B, the outer shape of the vibrating membrane 30 may be circular. At this time, the vibration film 30 and the first and second through holes 12 and 14 may have a circular shape with (substantially) the same diameter. However, the vibration film 30 may be larger or smaller than the first and second through holes 12 and 14. In addition, the vibration film 30 has first and second surfaces 35 and 37. The first surface 35 is a surface facing the first space 102, and the second surface 37 is a surface facing the second space 104.

  In the present embodiment, the vibrating membrane 30 may be provided such that the normal line extends in parallel with the surface 15 of the housing 10 as shown in FIG. In other words, the vibration film 30 may be provided so as to be orthogonal to the surface 15. The vibration film 30 may be disposed on the side (near the side) of the second through hole 14. That is, the vibration film 30 may be arranged such that the distance from the first through hole 12 and the distance from the second through hole 14 are not equal. However, as a modification, the vibration film 30 may be disposed between the first and second through holes 12 and 14 (not shown).

  In the present embodiment, the partition member 20 may include a holding portion 32 that holds the vibrating membrane 30 as shown in FIGS. 2 (A) and 2 (B). The holding unit 32 may be in close contact with the inner wall surface of the housing 10. The first and second spaces 102 and 104 can be hermetically separated by bringing the holding portion 32 into close contact with the inner wall surface of the housing 10.

  The microphone unit 1 according to the present embodiment includes an electric signal output circuit 40 that outputs an electric signal based on the vibration of the vibrating membrane 30. At least a part of the electric signal output circuit 40 may be formed in the internal space 100 of the housing 10. The electric signal output circuit 40 may be formed on the inner wall surface of the housing 10, for example. That is, in the present embodiment, the housing 10 may be used as a circuit board for an electric circuit.

  FIG. 4 shows an example of an electric signal output circuit 40 applicable to this embodiment. The electric signal output circuit 40 may be configured to amplify and output an electric signal based on a change in capacitance of the capacitor 42 (capacitor-type microphone having the vibrating membrane 30) by the signal amplifying circuit 44. The capacitor 42 may constitute a part of the diaphragm unit 41, for example. The electrical signal output circuit 40 may include a charge-up circuit 46 and an operational amplifier 48. As a result, it is possible to accurately acquire a change in the capacitance of the capacitor 42. In the present embodiment, for example, the capacitor 42, the signal amplification circuit 44, the charge-up circuit 46, and the operational amplifier 48 may be formed on the inner wall surface of the housing 10. The electric signal output circuit 40 may include a gain adjustment circuit 45. The gain adjustment circuit 45 plays a role of adjusting the amplification factor (gain) of the signal amplification circuit 44. The gain adjustment circuit 45 may be provided inside the housing 10 or may be provided outside the housing 10.

  However, when a silicon microphone is applied as the vibration film 30, the electric signal output circuit 40 may be realized by an integrated circuit formed on a semiconductor substrate of the silicon microphone.

  The electric signal output circuit 40 may further include a conversion circuit that converts an analog signal into a digital signal, a compression circuit that compresses (encodes) the digital signal, and the like.

  The microphone unit 1 according to the present embodiment may be configured as described above. According to the microphone unit 1, a highly accurate noise removal function can be realized with a simple configuration. Hereinafter, the principle of noise removal of the microphone unit 1 will be described.

1-2. Noise Removal Principle of Microphone Unit 1 (1) Structure of Microphone Unit 1 and Vibration Principle of Vibration Film 30 First, the vibration principle of the vibration film 30 derived from the structure of the microphone unit 1 will be described.

  In the present embodiment, the vibrating membrane 30 receives sound pressure from both sides (first and second 35, 37). Therefore, if sound pressures of the same magnitude are simultaneously applied to both sides of the vibration film 30, the two sound pressures cancel each other out with the vibration film 30, and do not become a force for vibrating the vibration film 30. Conversely, when there is a difference in sound pressure applied to both sides, the vibrating membrane 30 vibrates due to the difference in sound pressure.

  Further, the sound pressure of the sound wave incident on the first and second through holes 12 and 14 is evenly transmitted to the inner wall surfaces of the first and second spaces 102 and 104 (Pascal principle). Therefore, the surface (first surface 35) facing the first space 102 of the vibration film 30 receives a sound pressure equal to the sound pressure incident on the first through hole 12, and the second space 104 of the vibration film 30. The surface (second surface 37) facing the surface receives a sound pressure equal to the sound pressure incident on the second through hole 14.

  That is, the sound pressure received by the first and second surfaces 35 and 37 is the sound pressure of the sound incident on the first and second through holes 12 and 14, respectively. 2 is vibrated by the difference in sound pressure of the sound wave incident on the two surfaces 35 and 37 (first and second through holes 12 and 14).

と表すことができる。なお、式（１）中、ｋは比例定数である。図５には、式（１）を表すグラフを示すが、本図からもわかるように、音圧（音波の振幅）は、音源に近い位置（グラフの左側）では急激に減衰し、音源から離れるほどなだらかに減衰する。 (2) Properties of sound waves Sound waves attenuate as they travel through the medium, and sound pressure (sound wave intensity and amplitude) decreases. Since the sound pressure is inversely proportional to the distance from the sound source, the sound pressure P is related to the distance r from the sound source.

It can be expressed as. In equation (1), k is a proportionality constant. FIG. 5 shows a graph representing the expression (1). As can be seen from FIG. 5, the sound pressure (the amplitude of the sound wave) is abruptly attenuated at a position close to the sound source (left side of the graph). Attenuates gently as you move away.

  When the microphone unit 1 is applied to a close-talking voice input device, the user's voice is generated from the vicinity of the microphone unit 1 (first and second through holes 12, 14). Therefore, the user's voice is greatly attenuated between the first and second through holes 12 and 14, and the sound pressure of the user voice incident on the first and second through holes 12 and 14, that is, the first and second A large difference appears in the sound pressure of the user voice incident on the second surfaces 35 and 37.

  On the other hand, the noise component is present at a position farther from the microphone unit 1 (first and second through holes 12 and 14) than the sound of the user. For this reason, the sound pressure of noise hardly attenuates between the first and second through holes 12 and 14, and there is almost no difference in the sound pressure of noise incident on the first and second through holes 12 and 14. Does not appear.

(3) Noise Removal Principle As described above, the vibration film 30 vibrates due to the difference in sound pressure between sound waves that are simultaneously incident on the first and second surfaces 35 and 37. The difference between the sound pressures of noise incident on the first and second surfaces 35 and 37 is very small and is canceled by the vibration film 30. On the other hand, since the difference in sound pressure between user sounds incident on the first and second surfaces 35 and 37 is large, the user sound is not canceled by the vibration film 30 and vibrates the vibration film 30.

  From this, according to the microphone unit 1, it can be considered that the vibration film 30 vibrates only by a user's voice. Therefore, the electric signal output from the microphone unit 1 (electric signal output circuit 40) can be regarded as a signal indicating only the user voice from which noise is removed.

  That is, according to the microphone unit 1 according to the present embodiment, it is possible to provide a voice input device capable of acquiring an electric signal indicating a user voice from which noise is removed with a simple configuration.

1-3. Conditions for realizing a more accurate noise removal function with the microphone unit 1 As described above, according to the microphone unit 1, it is possible to obtain an electrical signal indicating only a user voice from which noise has been removed. . However, the sound wave includes a phase component. Therefore, a more accurate noise removal function can be realized by considering the phase difference between the sound waves incident on the first and second through holes 12 and 14 (first and second surfaces 35 and 37 of the vibration film 30). It is possible to derive conditions (design conditions for the microphone unit 1) that can be performed. Hereinafter, conditions that the microphone unit 1 should satisfy in order to realize a more accurate noise removal function will be described.

  According to the microphone unit 1, as described above, the sound pressure that vibrates the vibrating membrane 30 (difference in sound pressure applied to the first and second surfaces 35 and 37: hereinafter, appropriately referred to as “differential sound pressure”) Is regarded as a signal indicating the user voice. According to this microphone unit, the noise component included in the sound pressure (differential sound pressure) that vibrates the diaphragm 30 is smaller than the noise component included in the sound pressure incident on the first or second surface 35 or 37. Therefore, it can be evaluated that the noise removal function has been realized. Specifically, the noise intensity ratio indicating the ratio of the intensity of the noise component included in the differential sound pressure to the intensity of the noise component included in the sound pressure incident on the first or second surface 35 or 37 is the differential sound pressure. If the intensity of the included user voice component is smaller than the user voice intensity ratio indicating the ratio of the intensity of the user voice component included in the sound pressure incident on the first or second surface 35, 37 to the intensity of the user voice component, this noise removal function Can be evaluated as realized.

  Hereinafter, specific conditions to be satisfied by the microphone unit 1 (housing 10) in order to realize the noise removal function will be described.

と表すことができる。 First, the sound pressure of sound incident on the first and second surfaces 35 and 37 (first and second through holes 12 and 14) of the vibrating membrane 30 will be examined. If the distance from the sound source of the user voice to the first through hole 12 is R, and the distance between the centers of the first and second through holes 12 and 14 is Δr, the first and second are ignored if the phase difference is ignored. The sound pressures (intensities) P (S1) and P (S2) of the user voice that enter the through holes 12 and 14 are:

It can be expressed as.

と表される。 Therefore, the intensity of the user sound component included in the differential sound pressure with respect to the sound pressure intensity of the user sound incident on the first surface 35 (first through hole 12) when the phase difference of the user sound is ignored. The user voice intensity ratio ρ (P) indicating the ratio is

It is expressed.

  Here, when the microphone unit 1 is used in a close-talking voice input device, Δr can be considered to be sufficiently smaller than R.

と変形することができる。 Therefore, the above equation (4) is

And can be transformed.

  That is, it can be seen that the user voice intensity ratio when the phase difference of the user voice is ignored is expressed by the equation (A).

と表すことができる。なお、式中、αは位相差である。 By the way, considering the phase difference of the user voice, the sound pressures Q (S1) and Q (S2) of the user voice are

It can be expressed as. In the formula, α is a phase difference.

と表される。式（７）を考慮すると、ユーザ音声強度比ρ（Ｓ）の大きさは、

と表すことができる。 At this time, the user voice intensity ratio ρ (S) is

It is expressed. Considering equation (7), the magnitude of the user voice strength ratio ρ (S) is

It can be expressed as.

の関係を満たしていることが重要である。 In the equation (8), the term sinωt−sin (ωt−α) indicates the intensity ratio of the phase component, and the Δr / Rsinωt term indicates the intensity ratio of the amplitude component. Even if it is a user voice component, the phase difference component becomes noise with respect to the amplitude component, so that the intensity ratio of the phase component is sufficiently smaller than the intensity ratio of the amplitude component in order to accurately extract the user voice. is required. That is, sinωt−sin (ωt−α) and Δr / Rsinωt are

It is important to satisfy the relationship.

と表すことができるため、上述の式（Ｂ）は、

と表すことができる。 here,

Therefore, the above formula (B) can be expressed as

It can be expressed as.

を満たす必要があることがわかる。 Considering the amplitude component of Equation (10), the microphone unit 1 according to the present embodiment is

It turns out that it is necessary to satisfy.

と近似することができる。 Note that, as described above, Δr can be regarded as sufficiently small as compared with R, so sin (α / 2) can be regarded as sufficiently small,

And can be approximated.

と変形することができる。 Therefore, the formula (C) is

And can be transformed.

と表せば、式（Ｄ）は、

と変形することができる。 Also, the relationship between α and Δr, which are phase differences, is

The expression (D) can be expressed as

And can be transformed.

  That is, in the present embodiment, if the microphone unit 1 satisfies the relationship shown in the equation (E), the user voice can be extracted with high accuracy.

  Next, the sound pressure of noise incident on the first and second surfaces 35 and 37 (first and second through holes 12 and 14) will be examined.

と表すことができ、第１の面３５（第１の貫通穴１２）に入射する雑音成分の音圧の強度に対する、差分音圧に含まれる雑音成分の強度の比率を示す雑音強度比ρ（Ｎ）は、

と表すことができる。 Assuming that the amplitudes of the noise components incident on the first and second surfaces 35 and 37 are A and A ′, the sound pressures Q (N1) and Q (N2) of the noise considering the phase difference component are

The noise intensity ratio ρ (), which indicates the ratio of the intensity of the noise component included in the differential sound pressure to the intensity of the sound pressure of the noise component incident on the first surface 35 (first through hole 12). N)

It can be expressed as.

と変形することができる。 As described above, the amplitude (intensity) of the noise component incident on the first and second surfaces 35 and 37 (first and second through holes 12 and 14) is substantially the same, and A = A ′ can be handled. Therefore, the above equation (15) is

And can be transformed.

と表すことができる。 And the magnitude of the noise intensity ratio is

It can be expressed as.

と変形することができる。 Here, considering the above equation (9), equation (17) is

And can be transformed.

と変形することができる。 And considering equation (11), equation (18) is

And can be transformed.

と表すことができる。なお、Δｒ／Ｒとは、式（Ａ）に示すように、ユーザ音声の振幅成分の強度比である。式（Ｆ）から、このマイクロフォンユニット１では、雑音強度比がユーザ音声の強度比Δｒ／Ｒよりも小さくなることがわかる。 Here, referring to equation (D), the magnitude of the noise intensity ratio is

It can be expressed as. Note that Δr / R is the intensity ratio of the amplitude component of the user voice, as shown in Expression (A). From the formula (F), it can be seen that in the microphone unit 1, the noise intensity ratio is smaller than the intensity ratio Δr / R of the user voice.

  From the above, according to the microphone unit 1 in which the intensity ratio of the phase component of the user voice is smaller than the intensity ratio of the amplitude component (see Expression (B)), the noise intensity ratio is smaller than the user voice intensity ratio ( (See formula (F)). In other words, according to the microphone unit 1 designed such that the noise intensity ratio is smaller than the user voice intensity ratio, a highly accurate noise removal function can be realized.

1-4. Method for Manufacturing Microphone Unit 1 Hereinafter, a method for manufacturing the microphone unit 1 according to the present embodiment will be described. In the present embodiment, the value of Δr / λ indicating the ratio between the center-to-center distance Δr of the first and second through holes 12 and 14 and the noise wavelength λ and the noise intensity ratio (the intensity based on the phase component of the noise). The microphone unit 1 may be manufactured using data indicating a correspondence relationship with the ratio.

と表すことができる。 The intensity ratio based on the phase component of noise is expressed by the above-described equation (18). Therefore, the decibel value of the intensity ratio based on the phase component of noise is

It can be expressed as.

  Then, by assigning each value to α in Expression (20), it is possible to clarify the correspondence between the phase difference α and the intensity ratio based on the phase component of noise. FIG. 6 shows an example of data representing the correspondence between the phase difference and the intensity ratio when the horizontal axis is α / 2π and the vertical axis is the intensity ratio (decibel value) based on the phase component of noise. .

  The phase difference α can be expressed as a function of Δr / λ, which is the ratio of the distance Δr to the wavelength λ, as shown in Equation (12), and the horizontal axis in FIG. 6 is regarded as Δr / λ. Can do. That is, FIG. 6 can be said to be data indicating the correspondence between the intensity ratio based on the phase component of noise and Δr / λ.

  In the present embodiment, the microphone unit 1 is manufactured using this data. FIG. 7 is a flowchart for explaining a procedure for manufacturing the microphone unit 1 using this data.

  First, data (see FIG. 6) showing the correspondence between the noise intensity ratio (intensity ratio based on the phase component of noise) and Δr / λ is prepared (step S10).

  Next, a noise intensity ratio is set according to the application (step S12). In the present embodiment, it is necessary to set the noise intensity ratio so that the noise intensity decreases. Therefore, in this step, the noise intensity ratio is set to 0 dB or less.

  Next, a value of Δr / λ corresponding to the noise intensity ratio is derived based on the data (step S14).

  Then, a condition to be satisfied by Δr is derived by substituting the wavelength of the main noise into λ (step S16).

  As a specific example, let us consider a case where the microphone unit 1 whose noise intensity is reduced by 20 dB is manufactured in an environment where the main noise is 1 KHz and the wavelength is 0.347 m.

  First, the conditions for the noise intensity ratio to be 0 dB or less are examined. Referring to FIG. 6, it can be seen that the value of Δr / λ may be 0.16 or less in order to make the noise intensity ratio 0 dB or less. That is, it is understood that the value of Δr may be 55.46 mm or less, and this is a necessary condition for the microphone unit 1 (housing 10).

  Next, a condition for reducing the intensity of 1 kHz noise by 20 dB will be considered. Referring to FIG. 6, it can be seen that the value of Δr / λ may be set to 0.015 in order to reduce the noise intensity by 20 dB. When λ = 0.347 m, it can be seen that this condition is satisfied when the value of Δr is 5.199 mm or less. That is, if Δr is set to about 5.2 mm or less, a microphone unit having a noise removal function can be manufactured.

  When the microphone unit 1 according to the present embodiment is used in a close-talking voice input device, the distance between the sound source of the user voice and the microphone unit 1 (first and second through holes 12, 14) is as follows. Usually 5 cm or less. Further, the interval between the sound source of the user voice and the microphone unit 1 (first and second through holes 12 and 14) can be set by the design of the casing in which the microphone unit 1 is housed. Therefore, the value of Δr / R that is the intensity ratio of the user's voice becomes larger than 0.1 (noise intensity ratio), and it can be seen that the noise removal function is realized.

  In general, noise is not limited to a single frequency. However, the noise having a frequency lower than the noise assumed as the main noise has a longer wavelength than that of the main noise, so that the value of Δr / λ becomes small and is removed by the microphone unit 1. Further, the sound wave decays faster as the frequency is higher. For this reason, noise having a higher frequency than the noise assumed as the main noise attenuates faster than the main noise, so that the influence on the microphone unit 1 (vibrating membrane 30) can be ignored. Therefore, the microphone unit 1 according to the present embodiment can exhibit an excellent noise removal function even in an environment where noise having a frequency different from that assumed as main noise exists.

  Moreover, in this Embodiment, the noise which injects from the straight line which ties the 1st and 2nd through-holes 12 and 14 was assumed so that Formula (12) might also show. This noise is a noise in which the apparent distance between the first and second through holes 12 and 14 is the largest, and is a noise in which the phase difference is the largest in an actual use environment. In other words, the microphone unit 1 according to the present embodiment is configured to be able to remove noise with the largest phase difference. Therefore, according to the microphone unit 1 according to the present embodiment, it is possible to remove noise incident from all directions.

1-5. Effects Hereinafter, effects obtained by the microphone unit 1 will be summarized.

  As described above, according to the microphone unit 1, an electric signal indicating a sound from which a noise component has been removed can be obtained simply by acquiring an electric signal indicating the vibration of the vibration film 30 (an electric signal based on the vibration of the vibration film 30). Can be acquired. That is, the microphone unit 1 can realize a noise removal function without performing complicated analysis calculation processing. Therefore, a high-quality microphone unit capable of deep noise removal with a simple configuration can be provided. In particular, it is possible to provide a microphone unit capable of realizing a more accurate noise removal function by setting the center-to-center distance Δr between the first and second through holes 12 and 14 to 5.2 mm or less. it can.

  In the microphone unit 1, the housing 10 (positions of the first and second through holes 12 and 14) can be removed so that incident noise can be removed so that the noise intensity ratio based on the phase difference is maximized. Can be designed. Therefore, according to the microphone unit 1, noise incident from all directions can be removed. That is, according to the present invention, it is possible to provide a microphone unit that can remove noise incident from all directions.

  According to the microphone unit 1, it is also possible to remove the user voice component that is incident on the vibration film 30 (the first and second surfaces 35 and 37) after being reflected by a wall or the like. Specifically, since the user sound reflected by a wall or the like is incident on the microphone unit 1 after propagating a long distance, it can be regarded as a sound generated from a sound source that exists farther than a normal user sound, and Since the energy is largely lost due to the reflection, the sound pressure is not greatly attenuated between the first and second through holes 12 and 14 like the noise component. Therefore, according to the microphone unit 1, the user voice component incident after being reflected by the wall or the like is also removed (as a kind of noise) in the same manner as the noise.

  And if the microphone unit 1 is utilized, the signal which does not contain noise and shows a user voice can be acquired. Therefore, by using the microphone unit 1, highly accurate voice recognition, voice authentication, and command generation processing can be realized.

1-6. Voice Input Device Next, the voice input device 2 having the microphone unit 1 will be described.

(1) Configuration of Voice Input Device 2 First, the configuration of the voice input device 2 will be described. 8 and 9 are diagrams for explaining the configuration of the voice input device 2. The voice input device 2 described below is a close-talking type voice input device, for example, a voice communication device such as a mobile phone or a transceiver, or an information processing system using technology for analyzing input voice. (Voice authentication systems, voice recognition systems, command generation systems, electronic dictionaries, translators, voice input remote controllers, etc.) or recording equipment, amplifier systems (loudspeakers), microphone systems, etc. .

  FIG. 8 is a diagram for explaining the structure of the voice input device 2.

  The voice input device 2 has a housing 50. The casing 50 is a member that forms the outer shape of the voice input device 2. A basic posture may be set in the housing 50, thereby restricting the travel path of the user voice. The housing 50 may be formed with an opening 52 for receiving the user's voice.

  In the voice input device 2, the microphone unit 1 is installed inside the housing 50. The microphone unit 1 may be installed in the housing 50 so that the first and second through holes 12 and 14 communicate (overlap) with the opening 52. The microphone unit 1 may be installed in the housing 50 via the elastic body 54. Thereby, since the vibration of the housing | casing 50 becomes difficult to be transmitted to the microphone unit 1 (housing 10), the microphone unit 1 can be operated accurately.

  The microphone unit 1 may be installed in the housing 50 such that the first and second through holes 12 and 14 are arranged so as to be shifted along the traveling direction of the user voice. Then, the through hole disposed on the upstream side of the travel path of the user voice may be the first through hole 12, and the through hole disposed on the downstream side may be the second through hole 14. When the microphone unit 1 in which the vibration film 30 is disposed on the side of the second through hole 14 is disposed as described above, the user voice is transmitted to both surfaces of the vibration film 30 (first and second surfaces 35 and 37). Can be incident simultaneously. Specifically, in the microphone unit 1, the distance from the center of the first through hole 12 to the first surface 35 is substantially equal to the distance from the first through hole 12 to the second through hole 14. The time required for the user voice that has passed through the first through hole 12 to enter the first surface 35 is the second time when the user sound wave that has passed over the first through hole 12 passes through the second through hole 14. Is approximately equal to the time required to enter the surface 37. That is, the time taken for the voice uttered by the user to enter the first surface 35 is equal to the time taken for the sound to enter the second surface 37. Therefore, the user voice can be incident on the first and second surfaces 35 and 37 at the same time, and the vibration film 30 can be vibrated so that noise due to phase shift does not occur. In other words, since α = 0 and sinωt−sin (ωt−α) = 0 in the above-described equation (8), it can be seen that the Δr / Rsinωt term (only the amplitude component) is extracted. Therefore, even when a user voice having a high frequency band of about 7 KHz is input as a human voice, the influence of the phase distortion between the sound pressure incident on the first surface 35 and the sound pressure incident on the second surface 37. Can be ignored, and an electric signal accurately indicating the user's voice can be obtained.

(2) Function of Voice Input Device 2 Next, the function of the voice input device 2 will be described with reference to FIG. FIG. 9 is a block diagram for explaining the function of the voice input device 2.

  The voice input device 2 has a microphone unit 1. The microphone unit 1 outputs an electric signal generated based on the vibration of the vibration film 30. Note that the electric signal output from the microphone unit 1 is an electric signal indicating the user voice from which the noise component has been removed.

  The voice input device 2 may have an arithmetic processing unit 60. The arithmetic processing unit 60 performs various arithmetic processes based on the electric signal output from the microphone unit 1 (electric signal output circuit 40). The arithmetic processing unit 60 may perform analysis processing on the electrical signal. The arithmetic processing unit 60 may perform processing (so-called voice authentication processing) for identifying a person who has uttered a user voice by analyzing an output signal from the microphone unit 1. Or the arithmetic processing part 60 may perform the process (what is called a speech recognition process) which specifies the content of a user voice by analyzing the output signal of the microphone unit 1. The arithmetic processing unit 60 may perform processing for creating various commands based on an output signal from the microphone unit 1. The arithmetic processing unit 60 may perform processing for amplifying the output signal from the microphone unit 1. The arithmetic processing unit 60 may control the operation of the communication processing unit 70 described later. Note that the arithmetic processing unit 60 may realize the above functions by signal processing using a CPU or a memory. Or the arithmetic processing part 60 may implement | achieve each said function with exclusive hardware.

  The voice input device 2 may further include a communication processing unit 70. The communication processing unit 70 controls communication between the voice input device 2 and another terminal (such as a mobile phone terminal or a host computer). The communication processing unit 70 may have a function of transmitting a signal (an output signal from the microphone unit 1) to another terminal via a network. The communication processing unit 70 may also have a function of receiving signals from other terminals via a network. For example, the host computer may analyze the output signal acquired via the communication processing unit 70 and perform various information processing such as voice recognition processing, voice authentication processing, command generation processing, and data storage processing. Good. That is, the voice input device 2 may constitute an information processing system in cooperation with other terminals. In other words, the voice input device 2 may be regarded as an information input terminal that constructs an information processing system. However, the voice input device 2 may not have the communication processing unit 70.

  Note that the arithmetic processing unit 60 and the communication processing unit 70 described above may be arranged in the housing 50 as a packaged semiconductor device (integrated circuit device). However, the present invention is not limited to this. For example, the arithmetic processing unit 60 may be disposed outside the housing 50. When the arithmetic processing unit 60 is disposed outside the housing 50, the arithmetic processing unit 60 may acquire a differential signal via the communication processing unit 70.

  Note that the voice input device 2 may further include a display device such as a display panel, and a voice output device such as a speaker. The voice input device 2 may further include an operation key for inputting operation information.

  The voice input device 2 may have the above configuration. The voice input device 2 uses a microphone unit 1. Therefore, the voice input device 2 can acquire a signal indicating input voice that does not include noise, and can realize highly accurate voice recognition, voice authentication, and command generation processing.

  Further, when the voice input device 2 is applied to a microphone system, the user's voice output from the speaker is also removed as noise. Therefore, it is possible to provide a microphone system in which howling hardly occurs.

  10 to 12 show a mobile phone 300, a microphone (microphone system) 400, and a remote controller 500 as examples of the voice input device 2. FIG. 13 is a schematic diagram of an information processing system 600 including a voice input device 602 as an information input terminal and a host computer 604.

1-7. Modifications The present invention is not limited to the above-described embodiment, and various modifications can be made. The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

  Hereinafter, a specific modification is shown.

(1) First Modification FIG. 14 shows a microphone unit 3 according to a first modification of the embodiment to which the present invention is applied.

  The microphone unit 3 includes a vibration film 80. The vibrating membrane 80 constitutes a part of a partition member that divides the internal space 100 of the housing 10 into a first space 112 and a second space 114. The vibration film 80 is provided so that the normal line is orthogonal to the surface 15 (that is, parallel to the surface 15). The vibration film 80 may be provided on the side of the second through hole 14 so as not to overlap with the first and second through holes 12 and 14. Further, the vibration film 80 may be disposed with a space from the inner wall surface of the housing 10.

(2) Second Modification FIG. 15 shows a microphone unit 4 according to a second modification of the embodiment to which the present invention is applied.

  The microphone unit 4 includes a vibration film 90. The vibration film 90 constitutes a part of a partition member that divides the internal space 100 of the housing 10 into a first space 122 and a second space 124. The vibration film 90 is provided so that the normal line is orthogonal to the surface 15. The vibration film 90 may be provided so as to be flush with the inner wall surface (surface opposite to the surface 15) of the housing 10. The vibration film 90 may be provided so as to block the second through hole 14 from the inside (inner space 100) of the housing 10. That is, in the microphone unit 3, only the internal space of the second through hole 14 may be the second space 124, and the space other than the second space 124 in the internal space 100 may be the first space 122. According to this, it becomes possible to design the housing | casing 10 thinly.

(3) Third Modification FIG. 16 shows a microphone unit 5 according to a third modification of the embodiment to which the present invention is applied.

  The microphone unit 5 includes a housing 11. The housing 11 has an internal space 101. The internal space 101 is divided into a first region 132 and a second region 134 by the partition member 20. In the microphone unit 5, the partition member 20 is disposed on the side of the second through hole 14. In the microphone unit 5, the partition member 20 divides the internal space 101 so that the volumes of the first and second spaces 132 and 134 are equal.

(4) Fourth Modification FIG. 17 shows a microphone unit 6 according to a fourth modification of the embodiment to which the present invention is applied.

  The microphone unit 6 includes a partition member 21 as shown in FIG. The partition member 21 has a vibration film 31. The vibration film 31 is held inside the housing 10 so that the normal line obliquely intersects the surface 15.

(5) Fifth Modification FIG. 18 shows a microphone unit 7 according to a fifth modification of the embodiment to which the present invention is applied.

  In the microphone unit 7, as shown in FIG. 18, the partition member 20 is disposed between the first and second through holes 12 and 14. That is, the distance between the first through hole 12 and the partition member 20 is equal to the distance between the second through hole 14 and the partition member 20. In the microphone unit 7, the partition member 20 may be arranged so as to equally divide the internal space 100 of the housing 10.

(6) Sixth Modification FIG. 19 shows a microphone unit 8 according to a sixth modification of the embodiment to which the present invention is applied.

  In the microphone unit 8, the housing has a convex curved surface 16 as shown in FIG. 19. The first and second through holes 12 and 14 are formed on the convex curved surface 16.

(7) Seventh Modification FIG. 20 shows a microphone unit 9 according to a seventh modification of the embodiment to which the present invention is applied.

  In the microphone unit 9, the housing has a concave curved surface 17 as shown in FIG. 20. The first and second through holes 12 and 14 may be disposed on both sides of the concave curved surface 17. However, the first and second through holes 12 and 14 may be formed in the concave curved surface 17.

(8) Eighth Modification FIG. 21 shows a microphone unit 13 according to an eighth modification of the embodiment to which the present invention is applied.

  In the microphone unit 13, the casing has a spherical surface 18 as shown in FIG. 21. The bottom surface of the spherical surface 18 may be circular, but is not limited thereto, and the bottom surface may be elliptical. The first and second through holes 12 and 14 are formed in the spherical surface 18.

  These microphone units can also provide the same effects as described above. Therefore, by acquiring an electrical signal based on the vibration of the diaphragm, it is possible to acquire an electrical signal indicating only the user voice that does not include a noise component.

2-1. Configuration of Integrated Circuit Device First, the configuration of an integrated circuit device 1 according to an embodiment to which the present invention is applied will be described with reference to FIGS. The integrated circuit device 1 according to the present embodiment is configured as a voice input element (microphone element), and can be applied to a close-talking voice input device or the like.

  The integrated circuit device 1 according to the present embodiment includes a semiconductor substrate 1100 as shown in FIGS. 22 is a perspective view of the integrated circuit device 1001 (semiconductor substrate 1100), and FIG. 23 is a cross-sectional view of the integrated circuit device 1001. The semiconductor substrate 1100 may be a semiconductor chip. Alternatively, the semiconductor substrate 1100 may be a semiconductor wafer having a plurality of regions to be the integrated circuit device 1001. The semiconductor substrate 1100 may be a silicon substrate.

  A first vibration film 1012 is formed on the semiconductor substrate 1100. The first vibrating membrane 1012 may be the bottom of the first recess 1102 formed from a given surface 1101 of the semiconductor substrate 1100. The first vibration film 1012 is a vibration film constituting the first microphone 1010. That is, the first vibrating membrane 1012 is formed so as to vibrate when a sound wave is incident thereon, and constitutes the first microphone 1010 in a pair with the first electrodes 1014 arranged to face each other with a space therebetween. . When sound waves are incident on the first vibration film 1012, the first vibration film 1012 vibrates, the distance between the first vibration film 1012 and the first electrode 1014 changes, and the first vibration film 1012 and the first vibration film 1012 change. The capacitance between the electrode 1014 and the first electrode 1014 changes. By outputting this change in capacitance as, for example, a change in voltage, a sound wave that vibrates the first vibration film 1012 (a sound wave incident on the first vibration film 1012) is converted into an electric signal (voltage signal). Can be output. Hereinafter, the voltage signal output from the first microphone 1010 is referred to as a first voltage signal.

  A second vibration film 1022 is formed on the semiconductor substrate 1100. The second vibrating membrane 1022 may be the bottom of the second recess 1104 formed from a given surface 1101 of the semiconductor substrate 1100. The second vibration film 1022 is a vibration film constituting the second microphone 1020. That is, the second vibrating membrane 1022 is formed so as to vibrate when a sound wave is incident thereon, and forms a second microphone 1020 in a pair with the second electrode 1024 arranged to face the gap. . The second microphone 1020 converts a sound wave that vibrates the second vibration film 1022 (a sound wave incident on the second vibration film 22) into a voltage signal by the same action as the first microphone 1010 and outputs the voltage signal. . Hereinafter, the voltage signal output from the second microphone 1020 is referred to as a second voltage signal.

  In the present embodiment, the first and second vibration films 1012 and 1022 are formed on the semiconductor substrate 1100, and may be silicon films, for example. That is, the first and second microphones 1010 and 1020 may be silicon microphones (Si microphones). By using the silicon microphone, the first and second microphones 1010 and 1020 can be reduced in size and performance. The first and second vibrating membranes 1012 and 1022 may be arranged so that the normal lines are parallel to each other. Further, the first and second vibrating membranes 1012 and 1022 may be arranged so as to be shifted in a direction orthogonal to the normal line.

  The first and second electrodes 1014 and 1024 may be part of the semiconductor substrate 1100, or may be a conductor disposed on the semiconductor substrate 1100. The first and second electrodes 1014 and 1024 may have a structure that is not affected by sound waves. For example, the first and second electrodes 1014 and 1024 may have a mesh structure.

  An integrated circuit 1016 is formed on the semiconductor substrate 1100. The configuration of the integrated circuit 1016 is not particularly limited, and may include, for example, an active element such as a transistor or a passive element such as a resistor.

  The integrated circuit device according to this embodiment includes a differential signal generation circuit 1030. The difference signal generation circuit 1030 receives the first voltage signal and the second voltage signal, and generates (outputs) a difference signal indicating the difference between the two. The difference signal generation circuit 1030 performs a process for generating a difference signal without performing an analysis process such as Fourier analysis on the first and second voltage signals. The differential signal generation circuit 1030 may be a part of the integrated circuit 1016 configured on the semiconductor substrate 1100. FIG. 24 shows an example of a circuit diagram of the differential signal generation circuit 1030, but the circuit configuration of the differential signal generation circuit 1030 is not limited to this.

  Note that the integrated circuit device 1001 according to this embodiment may further include a signal amplifier circuit that amplifies the differential signal. The signal amplifier circuit may constitute part of the integrated circuit 1016. However, the integrated circuit device may be configured not to include a signal amplifier circuit.

  In the integrated circuit device 1001 according to this embodiment, the first and second vibrating membranes 1012 and 1022 and the integrated circuit 1016 (difference signal generation circuit 1030) are formed on one semiconductor substrate 1100. The semiconductor substrate 1100 may be regarded as so-called MEMS (Micro Electro Mechanical Systems). By forming the first and second vibrating membranes 1012 and 1022 on the same substrate (semiconductor substrate 1100), the first and second vibrating membranes 1012 and 1022 can be accurately formed, The second vibrating membranes 1012 and 1022 can be extremely close to each other.

  Note that the integrated circuit device 1001 according to the present embodiment realizes a function of removing a noise component by using a difference signal indicating a difference between the first and second voltage signals, as will be described later. In order to realize this function with high accuracy, the first and second vibrating membranes 1012 and 1022 may be arranged to satisfy certain restrictions. Although details of the constraints to be satisfied by the first and second vibrating membranes 1012 and 1014 will be described later, in the present embodiment, the first and second vibrating membranes 1012 and 1022 have a noise intensity ratio and an input voice intensity. You may arrange | position so that it may become smaller than ratio. As a result, the difference signal can be regarded as a signal indicating the audio component from which the noise component has been removed. The first and second vibrating membranes 1012 and 1022 may be arranged, for example, such that the center-to-center distance Δr is 5.2 mm or less.

  The integrated circuit device 1001 according to this embodiment may be configured as described above. According to this, an integrated circuit device capable of realizing a highly accurate noise removal function can be provided. The principle will be described later.

2-2. Noise Removal Function Hereinafter, the principle of voice removal by the integrated circuit device 1001 and the conditions for realizing it will be described.

(1) Principle of noise removal First, the principle of noise removal will be described.

と表すことができる。なお、式（１）中、ｋは比例定数である。図５には、式（１）を表すグラフを示すが、本図からもわかるように、音圧（音波の振幅）は、音源に近い位置（グラフの左側）では急激に減衰し、音源から離れるほどなだらかに減衰する。本実施の形態に係る集積回路装置では、この減衰特性を利用して雑音成分を除去する。 The sound wave attenuates as it travels through the medium, and the sound pressure (the intensity and amplitude of the sound wave) decreases. Since the sound pressure is inversely proportional to the distance from the sound source, the sound pressure P is related to the distance R from the sound source.

It can be expressed as. In equation (1), k is a proportionality constant. FIG. 5 shows a graph representing the expression (1). As can be seen from FIG. 5, the sound pressure (the amplitude of the sound wave) is abruptly attenuated at a position close to the sound source (left side of the graph). Attenuates gently as you move away. In the integrated circuit device according to the present embodiment, noise components are removed using this attenuation characteristic.

  In other words, when the integrated circuit device 1001 is applied to a close-talking sound input device, the user speaks at a position closer to the integrated circuit device 1001 (first and second vibrating membranes 1012 and 1022) than a noise source. Will be issued. Therefore, the user's voice is greatly attenuated between the first and second vibrating membranes 1012 and 1022, and a difference appears in the intensity of the user voice included in the first and second voltage signals. On the other hand, the noise component is hardly attenuated between the first and second vibrating membranes 1012 and 1022 because the sound source is farther than the user's voice. Therefore, it can be considered that no difference appears in the intensity of noise included in the first and second voltage signals. From this, if the difference between the first and second voltage signals is detected, the noise is eliminated, and only the voice component of the user uttered in the vicinity of the integrated circuit device 1 remains. That is, by detecting the difference between the first and second voltage signals, it is possible to obtain a voltage signal (difference signal) that does not include a noise component and that indicates only the user's voice component. And according to this integrated circuit device 1, the signal which shows a user voice from which noise was removed accurately can be acquired by simple processing which only generates the difference signal which shows the difference of two voltage signals.

  However, the sound wave has a phase component. Therefore, in order to realize a more accurate noise removal function, it is necessary to consider the phase difference between the speech component and the noise component included in the first and second voltage signals.

  Hereinafter, specific conditions that the integrated circuit device 1 should satisfy in order to realize the noise removal function by generating the differential signal will be described.

(2) Specific conditions to be satisfied by the integrated circuit device According to the integrated circuit device 1001, as described above, the difference signal indicating the difference between the first and second voltage signals can be converted into an input voice signal that does not include noise. Consider it. According to this integrated circuit device, it can be evaluated that the noise removal function can be realized when the noise component included in the differential signal is smaller than the noise component included in the first or second voltage signal. Specifically, the noise intensity ratio indicating the ratio of the intensity of the noise component included in the difference signal to the intensity of the noise component included in the first or second voltage signal is equal to the intensity of the audio component included in the difference signal. If the ratio is smaller than the voice intensity ratio indicating the ratio of the voice component included in the first or second voltage signal, it can be evaluated that the noise removal function has been realized.

  Hereinafter, specific conditions that the integrated circuit device 1001 (first and second vibrating membranes 1012 and 1022) should satisfy in order to realize this noise removal function will be described.

と表すことができる。 First, the sound pressure of sound incident on the first and second microphones 1010 and 1020 (first and second vibrating membranes 1012 and 1022) will be examined. If the distance from the sound source of the input voice (user's voice) to the first diaphragm 1012 is R, and the phase difference is ignored, the sound pressure of the input voice acquired by the first and second microphones 1010 and 1020 (Strength) P (S1) and P (S2) are

It can be expressed as.

と表される。 Therefore, a speech intensity ratio ρ (P) indicating the ratio of the strength of the input speech component included in the difference signal to the strength of the input speech component acquired by the first microphone 10 when the phase difference of the input speech is ignored. Is

It is expressed.

と変形することができる。 Here, when the integrated circuit device according to the present embodiment is a microphone element used in a close-talking voice input device, Δr can be considered to be sufficiently smaller than R, and therefore, the above equation (4) )

And can be transformed.

  That is, it can be seen that the voice intensity ratio when the phase difference of the input voice is ignored is expressed by the equation (A).

と表すことができる。なお、式中、αは位相差である。 By the way, considering the phase difference of the input voice, the sound pressures Q (S1) and Q (S2) of the user voice are

It can be expressed as. In the formula, α is a phase difference.

と表される。式（７）を考慮すると、音声強度比ρ（Ｓ）の大きさは、

と表すことができる。 At this time, the voice intensity ratio ρ (S) is

It is expressed. Considering equation (7), the magnitude of the voice intensity ratio ρ (S) is

It can be expressed as.

の関係を満たしていることが必要である。 By the way, in equation (8), the term sinωt−sin (ωt−α) indicates the intensity ratio of the phase component, and the Δr / Rsinωt term indicates the intensity ratio of the amplitude component. Even if it is an input voice component, the phase difference component becomes noise with respect to the amplitude component. Therefore, in order to accurately extract the input voice (user's voice), the intensity ratio of the phase component should Must be sufficiently small. That is, sinωt−sin (ωt−α) and Δr / Rsinωt are

It is necessary to satisfy the relationship.

と表すことができるため、上述の式（Ｂ）は、

と表すことができる。 here,

Therefore, the above formula (B) can be expressed as

It can be expressed as.

を満たす必要があることがわかる。 Considering the amplitude component of equation (10), the integrated circuit device 1 according to the present embodiment is

It turns out that it is necessary to satisfy.

と近似することができる。 Note that, as described above, Δr can be regarded as sufficiently small as compared with R, so sin (α / 2) can be regarded as sufficiently small,

And can be approximated.

と変形することができる。 Therefore, the formula (C) is

And can be transformed.

と表せば、式（Ｄ）は、

と変形することができる。 Also, the relationship between α and Δr, which are phase differences, is

The expression (D) can be expressed as

And can be transformed.

  In other words, in the present embodiment, in order to accurately extract the input voice (user's voice), it is necessary for the integrated circuit device 1 to satisfy the relationship represented by the equation (E).

  Next, the sound pressure of noise incident on the first and second microphones 10 and 20 (first and second vibrating membranes 12 and 22) will be examined.

と表すことができ、第１のマイクロフォン１０で取得される雑音成分の強度に対する、差分信号に含まれる雑音成分の強度の比率を示す雑音強度比ρ（Ｎ）は、

と表すことができる。 Assuming that the amplitudes of the noise components acquired by the first and second microphones 10 and 20 are A and A ′, the sound pressures Q (N1) and Q (N2) of the noise considering the phase difference component are

The noise intensity ratio ρ (N) indicating the ratio of the intensity of the noise component included in the difference signal to the intensity of the noise component acquired by the first microphone 10 is expressed as follows:

It can be expressed as.

と変形することができる。 As described above, the amplitudes (intensities) of the noise components acquired by the first and second microphones 10 and 20 are substantially the same, and can be handled as A = A ′. Therefore, the above equation (15) is

And can be transformed.

と表すことができる。 And the magnitude of the noise intensity ratio is

It can be expressed as.

と変形することができる。 Here, considering the above equation (9), equation (17) is

And can be transformed.

と変形することができる。 And considering equation (11), equation (18) is

And can be transformed.

と表すことができる。なお、Δｒ／Ｒとは、式（Ａ）に示すように、入力音声（ユーザ音声）の振幅成分の強度比である。式（Ｆ）から、この集積回路装置１では、雑音強度比が入力音声の強度比Δｒ／Ｒよりも小さくなることがわかる。 Here, referring to equation (D), the magnitude of the noise intensity ratio is

It can be expressed as. Note that Δr / R is the intensity ratio of the amplitude component of the input voice (user voice) as shown in Expression (A). From the equation (F), it can be seen that in this integrated circuit device 1, the noise intensity ratio is smaller than the intensity ratio Δr / R of the input voice.

  From the above, according to the integrated circuit device 1 in which the intensity ratio of the phase component of the input sound is smaller than the intensity ratio of the amplitude component (see equation (B)), the noise intensity ratio is smaller than the input sound intensity ratio. (See formula (F)). In other words, according to the integrated circuit device 1 designed so that the noise intensity ratio is smaller than the input voice intensity ratio, a highly accurate noise removal function can be realized.

2-3. Hereinafter, a method for manufacturing an integrated circuit device according to the present embodiment will be described. In the present embodiment, the value of Δr / λ indicating the ratio between the center-to-center distance Δr of the first and second vibrating membranes 1012 and 1022 and the noise wavelength λ and the noise intensity ratio (the intensity based on the phase component of the noise). The integrated circuit device may be manufactured using data indicating the correspondence relationship with the ratio.

と表すことができる。 The intensity ratio based on the phase component of noise is expressed by the above-described equation (18). Therefore, the decibel value of the intensity ratio based on the phase component of noise is

It can be expressed as.

  Then, by substituting each value into α in Expression (20), it is possible to clarify the correspondence between the phase difference α and the intensity ratio based on the phase component of noise. FIG. 6 shows an example of data representing the correspondence between the phase difference and the intensity ratio when the horizontal axis is α / 2π and the vertical axis is the intensity ratio (decibel value) based on the phase component of noise. .

  The phase difference α can be expressed as a function of Δr / λ, which is the ratio of the distance Δr to the wavelength λ, as shown in Equation (12), and the horizontal axis in FIG. 5 is regarded as Δr / λ. Can do. That is, FIG. 5 can be said to be data indicating a correspondence relationship between the intensity ratio based on the phase component of noise and Δr / λ.

  In this embodiment, the integrated circuit device 1001 is manufactured using this data. FIG. 7 is a flowchart for explaining a procedure for manufacturing the integrated circuit device 1 using this data.

  First, data (see FIG. 6) showing the correspondence between the noise intensity ratio (intensity ratio based on the phase component of noise) and Δr / λ is prepared (step S10).

  Next, a noise intensity ratio is set according to the application (step S12). In the present embodiment, it is necessary to set the noise intensity ratio so that the noise intensity decreases. Therefore, in this step, the noise intensity ratio is set to 0 dB or less.

  Next, a value of Δr / λ corresponding to the noise intensity ratio is derived based on the data (step S14).

  Then, a condition to be satisfied by Δr is derived by substituting the wavelength of the main noise into λ (step S16).

  As a specific example, consider the case of manufacturing an integrated circuit device in which the noise intensity is reduced by 20 dB in an environment where the main noise is 1 KHz and the wavelength is 0.347 m.

  First, as a necessary condition, a condition for the noise intensity ratio to be 0 dB or less is examined. Referring to FIG. 6, it can be seen that the value of Δr / λ may be 0.16 or less in order to make the noise intensity ratio 0 dB or less. That is, it can be seen that the value of Δr should be 55.46 mm or less, which is a necessary condition for this integrated circuit device.

  Next, a condition for reducing the intensity of 1 kHz noise by 20 dB will be considered. Referring to FIG. 6, it can be seen that the value of Δr / λ may be set to 0.015 in order to reduce the noise intensity by 20 dB. When λ = 0.347 m, it can be seen that this condition is satisfied when the value of Δr is 5.199 mm or less. That is, if Δr is set to about 5.2 mm or less, an integrated circuit device having a noise removal function can be manufactured.

  Note that the integrated circuit device 1001 according to the present embodiment is used in a close-talking voice input device, and therefore, the sound source of the user's voice, the integrated circuit device 1001 (first or second vibrating membranes 1012 and 1022), and The interval is usually 5 cm or less. Further, the distance between the sound source of the user voice and the integrated circuit device 1001 (first and second vibrating membranes 1012 and 1022) can be controlled by the design of the housing. Therefore, the value of Δr / R, which is the intensity ratio of the input voice (user's voice), becomes larger than 0.1 (noise intensity ratio), and it can be seen that the noise removal function is realized.

  In general, noise is not limited to a single frequency. However, since noise having a frequency lower than that of noise assumed as main noise has a longer wavelength than that of main noise, the value of Δr / λ becomes small and is removed by the integrated circuit device. Further, the sound wave decays faster as the frequency is higher. For this reason, noise having a higher frequency than the noise assumed as the main noise attenuates faster than the main noise, so that the influence on the integrated circuit device can be ignored. Therefore, the integrated circuit device according to the present embodiment can exhibit an excellent noise removal function even in an environment where noise having a frequency different from that assumed as main noise exists.

  Further, in this embodiment, as can be seen from the equation (12), it is assumed that noise is incident on a straight line connecting the first and second vibrating membranes 1012 and 1022. This noise is a noise in which the apparent distance between the first and second vibrating membranes 1012 and 1022 is the largest, and is a noise in which the phase difference is the largest in an actual use environment. In other words, the integrated circuit device 1001 according to the present embodiment is configured to be able to remove noise with the largest phase difference. Therefore, according to the integrated circuit device 1001 according to the present embodiment, noise incident from all directions is removed.

2-4. Effects The effects achieved by the integrated circuit device 1001 will be summarized below.

  As described above, according to the integrated circuit device 1001, the sound component from which the noise component has been removed can be obtained only by generating a differential signal indicating the difference between the voltage signals acquired by the first and second microphones 1010 and 1020. Can be obtained. That is, in this voice input device, a noise removal function can be realized without performing complicated analysis calculation processing. Therefore, it is possible to provide an integrated circuit device (microphone element / audio input element) that can realize a highly accurate noise removal function with a simple configuration.

  In the integrated circuit device 1001, the first and second vibrating membranes 1012 and 1022 are arranged so that incident noise can be removed so that the noise intensity ratio based on the phase difference is maximized. Therefore, according to this integrated circuit device 1001, noise incident from all directions is removed. That is, according to the present invention, it is possible to provide an integrated circuit device capable of removing noise incident from all directions.

  Note that according to the integrated circuit device 1001, it is also possible to remove the user voice component incident on the integrated circuit device 1001 after being reflected by a wall or the like. Specifically, since the sound source of the user sound reflected by the wall or the like is incident on the integrated circuit device 1 after propagating a long distance, it can be regarded as being farther than the sound source of the normal user sound, and the energy is greatly increased by the reflection. Therefore, the sound pressure is not greatly attenuated between the first and second vibrating membranes 1012 and 1022, similarly to the noise component. Therefore, according to the integrated circuit device 1001, the user voice component incident after being reflected by a wall or the like is also removed in the same manner as noise (as a kind of noise).

  Further, according to the integrated circuit device 1001, the first and second vibrating membranes 1012 and 1022 and the differential signal generation circuit 1030 are formed on one semiconductor substrate 1100. According to this, the first and second vibrating membranes 1012 and 1022 can be formed with high accuracy, and the distance between the centers of the first and second vibrating membranes 1012 and 1022 can be extremely close. . Therefore, an integrated circuit device with high noise removal accuracy and a small external shape can be provided.

  If the integrated circuit device 1001 is used, a signal indicating input speech that does not include noise can be acquired. Therefore, by using this integrated circuit device, highly accurate voice recognition, voice authentication, and command generation processing can be realized.

2-5. Next, the voice input device 1002 having the integrated circuit device 1001 will be described.

(1) Configuration of Voice Input Device First, the configuration of the voice input device 2 will be described. 25 and 26 are diagrams for explaining the configuration of the voice input device 1002. Note that a voice input device 1002 described below is a close-talking voice input device, for example, a voice communication device such as a mobile phone or a transceiver, or an information processing system using technology for analyzing input voice. (Voice authentication system, voice recognition system, command generation system, electronic dictionary, translator, voice input remote controller, etc.), recording equipment, amplifier system (loudspeaker), microphone system, etc. .

  FIG. 25 is a diagram for explaining the structure of the voice input device 2002.

  The voice input device 1002 includes a housing 1040. The housing 1040 may be a member that forms the outer shape of the voice input device 1002. A basic posture may be set for the housing 1040, and thereby the travel path of the input voice (user's voice) can be restricted. The housing 1040 may have an opening 1042 for receiving input voice (user's voice).

  In the voice input device 1002, the integrated circuit device 1001 is installed in the housing 1040. The integrated circuit device 1001 may be installed in the housing 1040 so that the first and second recesses 1102 and 1104 communicate with the opening 1042. The integrated circuit device 1001 may be installed in the housing 1040 so that the first and second vibrating membranes 1012 and 1022 are displaced along the traveling path of the input sound. The vibration film disposed on the upstream side of the traveling path of the input voice may be the first vibration film 1012, and the vibration film disposed on the downstream side may be the second vibration film 1022.

  Next, the function of the voice input device 1002 will be described with reference to FIG. FIG. 26 is a block diagram for explaining the function of the voice input device 1002.

  The voice input device 1002 includes first and second microphones 1010 and 1020. The first and second microphones 1010 and 1020 output first and second voltage signals.

  The voice input device 1002 includes a differential signal generation circuit 1030. The difference signal generation circuit 1030 receives the first and second voltage signals output from the first and second microphones 1010 and 1020, and generates a difference signal indicating the difference between them.

  Note that the first and second microphones 1010 and 1020 and the differential signal generation circuit 1030 are realized by one semiconductor substrate 1100.

  The voice input device 1002 may have an arithmetic processing unit 1050. The arithmetic processing unit 1050 performs various arithmetic processes based on the difference signal generated by the difference signal generation circuit 1030. The arithmetic processing unit 1050 may perform analysis processing on the difference signal. The arithmetic processing unit 1050 may perform a process (so-called voice authentication process) for identifying the person who has emitted the input voice by analyzing the difference signal. Alternatively, the arithmetic processing unit 1050 may perform processing (so-called speech recognition processing) for specifying the content of the input speech by analyzing the difference signal. The arithmetic processing unit 1050 may perform processing for creating various commands based on the input voice. The arithmetic processing unit 1050 may perform processing for amplifying the difference signal. In addition, the arithmetic processing unit 1050 may control the operation of the communication processing unit 1060 described later. Note that the arithmetic processing unit 1050 may realize the above functions by signal processing using a CPU or a memory.

  The voice input device 1002 may further include a communication processing unit 1060. The communication processing unit 1060 controls communication between the voice input device and another terminal (such as a mobile phone terminal or a host computer). The communication processing unit 1060 may have a function of transmitting a signal (difference signal) to another terminal via a network. The communication processing unit 1060 may also have a function of receiving signals from other terminals via a network. For example, the host computer may analyze the differential signal acquired via the communication processing unit 1060 and perform various information processing such as voice recognition processing, voice authentication processing, command generation processing, and data storage processing. Good. That is, the voice input device may constitute an information processing system in cooperation with other terminals. In other words, the voice input device may be regarded as an information input terminal that constructs an information processing system. However, the voice input device may not have the communication processing unit 1060.

  Note that the arithmetic processing unit 1050 and the communication processing unit 1060 described above may be disposed in the housing 1040 as a packaged semiconductor device (integrated circuit device). However, the present invention is not limited to this. For example, the arithmetic processing unit 1050 may be disposed outside the housing 1040. When the arithmetic processing unit 1050 is disposed outside the housing 1040, the arithmetic processing unit 1050 may acquire a difference signal via the communication processing unit 1060.

  Note that the voice input device 1002 may further include a display device such as a display panel and a voice output device such as a speaker. In addition, the voice input device according to the present embodiment may further include an operation key for inputting operation information.

  The voice input device 1002 may have the above configuration. The voice input device 1002 uses the integrated circuit device 1 as a microphone element (voice input element). Therefore, the voice input device 1002 can acquire a signal indicating input voice that does not include noise, and can realize highly accurate voice recognition, voice authentication, and command generation processing.

  Further, when the voice input device 1002 is applied to a microphone system, the user's voice output from the speaker is also removed as noise. Therefore, it is possible to provide a microphone system in which howling hardly occurs.

2-6. Modified Examples Hereinafter, modified examples of the embodiment to which the present invention is applied will be described.

  FIG. 27 is a diagram for explaining the integrated circuit device 1003 according to this embodiment.

  The integrated circuit device 1003 according to this embodiment includes a semiconductor substrate 1200 as shown in FIG. First and second vibrating membranes 1012 and 1022 are formed on the semiconductor substrate 1200. Here, the first vibration film 1015 is the bottom of the first recess 1210 formed from the first surface 1201 of the semiconductor substrate 1200. The second vibration film 1025 is the bottom of the second recess 1220 formed from the second surface 1202 of the semiconductor substrate 1200 (the surface facing the first surface 1201). That is, according to the integrated circuit device 1003 (semiconductor substrate 1200), the first and second vibrating membranes 1015 and 1025 are arranged so as to be shifted in the normal direction (in the thickness direction of the semiconductor substrate 1200). In the semiconductor substrate 1200, the first and second vibrating membranes 1015 and 1025 may be arranged so that the normal distance is 5.2 mm or less. Alternatively, the first and second vibrating membranes 1015 and 1025 may be arranged so that the center-to-center distance is 5.2 mm or less.

  FIG. 28 is a diagram for explaining the voice input device 1004 in which the integrated circuit device 1003 is mounted. The integrated circuit device 1003 is mounted on the housing 1040. As shown in FIG. 28, the integrated circuit device 1003 may be mounted on the housing 1040 such that the first surface 1201 faces the surface of the housing 1040 where the opening 1042 is formed. The integrated circuit device 1003 may be mounted on the housing 1040 so that the first recess 1210 communicates with the opening 1042 and the second vibrating membrane 1025 overlaps with the opening 1042.

  In this embodiment mode, the integrated circuit device 1003 is configured such that the center of the opening 1212 that communicates with the first recess 1210 is a sound source of input sound, rather than the center of the second vibration film 1025 (the bottom surface of the second recess 1220). It may be installed so that it may be arrange | positioned in the position near. The integrated circuit device 1003 may be installed so that the input sound arrives at the first and second vibrating membranes 1015 and 1025 at the same time. For example, the integrated circuit device 1003 is installed such that the distance between the input sound source (model sound source) and the first diaphragm 1015 is the same as the distance between the model sound source and the second diaphragm 1025. Also good. The integrated circuit device 1003 may be installed in a housing in which a basic posture is set so as to satisfy the above conditions.

  According to the voice input device according to the present embodiment, it is possible to reduce a shift in incident time of input voices (user voices) incident on the first and second vibrating membranes 1015 and 1025. Therefore, since the difference signal can be generated so as not to include the phase difference component of the input sound, the amplitude component of the input sound can be accurately extracted.

  In addition, since the sound wave does not diffuse in the recess (first recess 1210), the amplitude of the sound wave is hardly attenuated. Therefore, in this voice input device, the intensity (amplitude) of the input voice that vibrates the first diaphragm 1015 can be regarded as the same as the intensity of the input voice in the opening 1212. Thus, even when the voice input device is configured so that the input voice reaches the first and second vibrating membranes 1015 and 1025 at the same time, the first and second vibrating membranes 1015 and 1025 are vibrated. A difference appears in the intensity of the input speech. Therefore, the input sound can be extracted by acquiring a differential signal indicating the difference between the first and second voltage signals.

  In summary, according to the voice input device, the amplitude component (difference signal) of the input voice can be acquired so as not to include noise based on the phase difference component of the input voice. Therefore, it is possible to realize a highly accurate noise removal function.

  Finally, FIGS. 29 to 31 show a mobile phone 1300, a microphone (microphone system) 1400, and a remote controller 1500, respectively, as examples of the voice input device according to the embodiment of the present invention. FIG. 32 shows a schematic diagram of an information processing system 1600 including a voice input device 1602 as an information input terminal and a host computer 1604.

3-1. Configuration of Voice Input Device According to this Embodiment First, the configuration of a voice input device 2001 according to an embodiment to which the present invention is applied will be described with reference to FIGS. Note that a voice input device 2001 described below is a close-talking voice input device, for example, a voice communication device such as a mobile phone or a transceiver, or an information processing system using technology for analyzing input voice. (Voice authentication system, voice recognition system, command generation system, electronic dictionary, translator, voice input remote controller, etc.), recording equipment, amplifier system (loudspeaker), microphone system, etc. .

  The voice input device according to the present embodiment includes a first microphone 2010 having a first vibration film 2012 and a second microphone 2020 having a second vibration film 2022. Here, the microphone is an electroacoustic transducer that converts an acoustic signal into an electrical signal. The first and second microphones 2010 and 2020 may be converters that output the vibrations of the first and second diaphragms 2012 and 2022 (diaphragm) as voltage signals, respectively.

  In the voice input device according to the present embodiment, the first microphone 2010 generates a first voltage signal. Further, the second microphone 2020 generates a second voltage signal. That is, the voltage signals generated by the first and second microphones 2010 and 2020 may be called first and second voltage signals, respectively.

  The mechanism of the first and second microphones 2010 and 2020 is not particularly limited. FIG. 34 shows a structure of a condenser microphone 2100 as an example of a microphone applicable to the first and second microphones 2010 and 2020. The condenser microphone 2100 has a vibration film 2102. The vibration film 2102 is a film (thin film) that vibrates in response to sound waves, has conductivity, and forms one end of the electrode. The condenser microphone 2100 also has an electrode 2104. The electrode 2104 is disposed to face the vibration film 2102. Thereby, the vibrating membrane 2102 and the electrode 2104 form a capacitance. When a sound wave enters the condenser microphone 2100, the vibration film 2102 vibrates, the distance between the vibration film 2102 and the electrode 2104 changes, and the capacitance between the vibration film 2102 and the electrode 2104 changes. By outputting this change in capacitance as, for example, a change in voltage, a sound wave incident on the condenser microphone 2100 can be converted into an electrical signal. In the capacitor microphone 2100, the electrode 2104 may have a structure that is not affected by sound waves. For example, the electrode 2104 may have a mesh structure.

  However, the microphone applicable to the present invention is not limited to the condenser microphone, and any microphone that is already known can be applied. For example, as the first and second microphones 2010 and 2020, electrodynamic (dynamic), electromagnetic (magnetic), and piezoelectric (crystal) microphones may be applied.

  The first and second microphones 2010 and 2020 may be silicon microphones (Si microphones) in which the first and second vibrating membranes 2012 and 2022 are made of silicon. By using the silicon microphone, the first and second microphones 2010 and 2020 can be reduced in size and performance. At this time, the first and second microphones 2010 and 2020 may be configured as one integrated circuit device. That is, the first and second microphones 2010 and 2020 may be configured on one semiconductor substrate. At this time, a differential signal generation unit 2030 described later may also be formed on the same semiconductor substrate. That is, the first and second microphones 2010 and 2020 may be configured as so-called MEMS (Micro Electro Mechanical Systems). However, the first microphone 2010 and the second microphone 2020 may be configured as separate silicon microphones.

  In the voice input device according to the present embodiment, as described later, a function of removing a noise component is realized by using a differential signal indicating a difference between the first and second voltage signals. In order to realize this function, the first and second microphones (first and second vibrating membranes 2012 and 2022) are arranged so as to satisfy certain restrictions. Although details of the constraints to be satisfied by the first and second vibrating membranes 2012 and 2022 will be described later, in the present embodiment, the first and second vibrating membranes 2012 and 2022 (first and second microphones 2010, 2020) is arranged such that the noise intensity ratio is smaller than the input voice intensity ratio. As a result, the difference signal can be regarded as a signal indicating the audio component from which the noise component has been removed. For example, the first and second vibrating membranes 2012 and 2022 may be arranged such that the center-to-center distance is 5.2 mm or less.

  In the voice input device according to the present embodiment, the directions of the first and second vibrating membranes 2012 and 2022 are not particularly limited. The first and second vibrating membranes 2012 and 2022 may be arranged so that the normal lines are parallel. At this time, the first and second vibrating membranes 2012 and 2022 may be arranged so that the normal lines are not the same straight line. For example, the first and second vibrating membranes 2012 and 2022 may be arranged on the surface of a base (not shown) (for example, a circuit board) with a space therebetween. Alternatively, the first and second vibrating membranes 2012 and 2022 may be arranged shifted in the normal direction. However, the first and second vibrating membranes 2012 and 2022 may be arranged so that the normal lines do not become parallel. The first and second vibrating membranes 2012 and 2022 may be arranged so that the normal lines are orthogonal to each other.

  The voice input device according to this embodiment includes a differential signal generation unit 2030. The difference signal generation unit 2030 generates a difference signal indicating a difference (voltage difference) between the first voltage signal acquired by the first microphone 2010 and the second voltage signal acquired by the second microphone 2020. To do. The difference signal generation unit 2030 performs a process of generating a difference signal indicating a difference between the first and second voltage signals without performing an analysis process such as Fourier analysis. The function of the difference signal generation unit 2030 may be realized by a dedicated hardware circuit (difference signal generation circuit) or may be realized by signal processing by a CPU or the like.

  The voice input device according to the present embodiment may further include a signal amplifying unit that amplifies the differential signal. The difference signal generation unit 2030 and the signal amplification unit may be realized by one control circuit. However, the voice input device according to the present embodiment may be configured not to have a signal amplifying unit therein.

  FIG. 35 shows an example of a circuit that can realize the differential signal generation unit 2030 and the signal amplification unit. According to the circuit shown in FIG. 35, the first and second voltage signals are received, and a signal obtained by amplifying the difference signal indicating the difference by 10 times is output. However, the circuit configuration for realizing the differential signal generation unit 2030 and the signal amplification unit is not limited to this.

  The voice input device according to this embodiment may include a housing 2040. At this time, the outer shape of the voice input device may be configured by the housing 2040. A basic posture may be set for the housing 2040, thereby restricting the travel path of the input voice. The first and second vibrating membranes 2012 and 2022 may be formed on the surface of the housing 2040. Alternatively, the first and second vibrating membranes 2012 and 2022 may be disposed inside the housing 2040 so as to face an opening (sound entrance) formed in the housing 2040. The first and second vibrating membranes 2012 and 2022 may be arranged so that the distances from the sound source (incident sound model sound source) are different. For example, as shown in FIG. 33, the basic posture of the housing 2040 may be set so that the travel path of the input voice is along the surface of the housing 2040. The first and second vibrating membranes 2012 and 2022 may be disposed along the traveling path of the input voice. Then, the vibration film disposed on the upstream side of the traveling path of the input sound may be the first vibration film 2012, and the vibration film disposed on the downstream side may be the second vibration film 2022.

  The voice input device according to this embodiment may further include an arithmetic processing unit 2050. The arithmetic processor 2050 performs various arithmetic processes based on the difference signal generated by the difference signal generator 2030. The arithmetic processing unit 2050 may perform analysis processing on the difference signal. The arithmetic processing unit 2050 may perform processing (so-called voice authentication processing) for identifying a person who has emitted the input voice by analyzing the difference signal. Alternatively, the arithmetic processing unit 2050 may perform processing (so-called speech recognition processing) for specifying the content of the input speech by analyzing the difference signal. The arithmetic processing unit 2050 may perform processing for creating various commands based on the input voice. The arithmetic processing unit 2050 may perform processing for amplifying the difference signal. Further, the arithmetic processing unit 2050 may control the operation of the communication processing unit 2060 described later. Note that the arithmetic processing unit 2050 may realize the above functions by signal processing using a CPU or a memory.

  The arithmetic processing unit 2050 may be disposed inside the housing 2040, but may be disposed outside the housing 2040. When the arithmetic processing unit 2050 is arranged outside the housing 2040, the arithmetic processing unit 2050 may acquire the difference signal via the communication processing unit 2060 described later.

  The voice input device according to the present embodiment may further include a communication processing unit 2060. The communication processing unit 2060 controls communication between the voice input device and another terminal (such as a mobile phone terminal or a host computer). The communication processing unit 2060 may have a function of transmitting a signal (difference signal) to another terminal via a network. The communication processing unit 2060 may also have a function of receiving signals from other terminals via a network. For example, the host computer may analyze the differential signal acquired via the communication processing unit 2060 and perform various information processing such as voice recognition processing, voice authentication processing, command generation processing, and data storage processing. Good. That is, the voice input device may constitute an information processing system in cooperation with other terminals. In other words, the voice input device may be regarded as an information input terminal that constructs an information processing system. However, the voice input device may not have the communication processing unit 2060.

  The audio input device according to the present embodiment may further include a display device such as a display panel and an audio output device such as a speaker. In addition, the voice input device according to the present embodiment may further include an operation key for inputting operation information.

  The voice input device according to the present embodiment may have the above configuration. According to this voice input device, a signal (voltage signal) indicating the voice component from which the noise component has been removed is generated by a simple process that simply outputs the difference between the first and second voltage signals. Therefore, according to the present invention, it is possible to provide a voice input device that can be miniaturized and has an excellent noise removal function. The principle, manufacturing method, and effects are the same as those described in 2-2 to 2-4.

3-2. Voice Input Device According to Another Embodiment Next, a voice input device according to another embodiment to which the present invention is applied will be described with reference to FIG.

  The voice input device according to the present embodiment includes a base 2070. A recess 2074 is formed in the main surface 2072 of the base 2070. In the voice input device according to this embodiment, the first vibration film 2012 (first microphone 2010) is disposed on the bottom surface 2075 of the recess 2074, and the second vibration film 2022 (on the main surface 2072 of the base 2070). A second microphone 2020) is arranged. The recess 2074 may extend perpendicular to the main surface 2072, and the bottom surface 2075 of the recess 2074 may be a surface parallel to the main surface 2072. The bottom surface 2075 may be a surface orthogonal to the recess 2074. The recess 2074 may have the same outer shape as the first vibrating membrane 2012.

  In the present embodiment, the recess 2074 may be shallower than the distance between the region 2076 and the opening 2078. That is, if the depth of the recess 2074 is d and the interval between the region 2076 and the opening 2078 is ΔG, the base 2070 may satisfy d ≦ ΔG. The base 2070 may satisfy 2d = ΔG. Note that ΔG may be 5.2 mm or less. Alternatively, the base 2070 may be configured such that a linear distance connecting the centers of the first and second vibrating membranes 2012 and 2022 is 5.2 mm or less.

  The base 2070 is installed such that the opening 2078 communicating with the recess 2074 is disposed at a position closer to the sound source of the input sound than the region 2076 in the main surface 2072 where the second vibrating membrane 2022 is disposed. The base 2070 may be installed so that the input sound arrives at the first and second vibrating membranes 2012 and 2022 at the same time. For example, the base 2070 may be installed such that the distance between the input sound source (model sound source) and the first diaphragm 2012 is the same as the distance between the model sound source and the second diaphragm 22. . The base 2070 may be installed in a housing in which a basic posture is set so as to satisfy the above conditions.

  According to the voice input device according to the present embodiment, it is possible to reduce a shift in incident time of input voices (user voices) incident on the first and second vibrating membranes 2012 and 2022. That is, since the difference signal can be generated so as not to include the phase difference component of the input sound, the amplitude component of the input sound can be accurately extracted.

  In addition, since the sound wave does not diffuse in the recess 74, the amplitude of the sound wave hardly attenuates. Therefore, in this voice input device, the intensity (amplitude) of the input voice that vibrates the first diaphragm 2012 can be regarded as the same as the intensity of the input voice in the opening 2078. Therefore, even when the voice input device is configured so that the input voice reaches the first and second vibrating membranes 2012 and 2022 at the same time, the first and second vibrating membranes 2012 and 2022 are vibrated. A difference appears in the intensity of the input speech. Therefore, the input sound can be extracted by acquiring a differential signal indicating the difference between the first and second voltage signals.

  In summary, according to the voice input device, the amplitude component (difference signal) of the input voice can be acquired so as not to include noise based on the phase difference component of the input voice. Therefore, it is possible to realize a highly accurate noise removal function.

  In addition, since the resonance frequency of the recess 2074 can be set high by setting the depth of the recess 2074 to ΔG or less (5.2 mm or less), it is possible to prevent the generation of resonance noise in the recess 2074. .

  FIG. 37 shows a modification of the voice input device according to this embodiment.

  The voice input device according to the present embodiment includes a base 2080. A main surface 2082 of the base 2080 is formed with a first recess 2084 and a second recess 2086 that is shallower than the first recess 2084. Δd, which is the difference between the depths of the first and second recesses 2084 and 2086, is between the first opening 2085 that communicates with the first recess 2084 and the second opening 2087 that communicates with the second recess 2086. It may be smaller than ΔG which is the interval. The first vibration film 2012 is disposed on the bottom surface of the first recess 2084, and the second vibration film 2022 is disposed on the bottom surface of the second recess 2086.

  Even with this voice input device, the same effects as described above can be obtained, so that a highly accurate noise removal function can be realized.

4-1. Voice Input / Output Device and Call Device FIG. 38 is a functional block diagram of the voice input / output device and the call device of this embodiment.

  The audio input / output device 3010 of this embodiment includes an audio input unit 3030 that generates a first audio signal 3034 based on an input from a microphone 3032, and an audio that outputs audio from a speaker 3046 based on a second audio signal 3048. Output unit 3040.

  The voice input unit 3030 includes a housing having an internal space, and the internal space provided in the housing divides the internal space into a first space and a second space, and at least a part thereof is configured by a vibration film. A partition member, and an electric signal output circuit that outputs an electric signal that is a first audio signal based on vibration of the diaphragm, wherein the casing includes the first space and an exterior of the casing A microphone unit in which a first through hole that communicates with a space and a second through hole that communicates between the second space and the external space of the housing may be mounted. Here, the microphone unit may be realized by the configuration described with reference to FIGS.

  In addition, the voice input unit 3030 includes a first diaphragm that forms a first microphone, a second diaphragm that forms a second microphone, and a first voltage signal acquired by the first microphone. A differential signal generation circuit that receives a second voltage signal acquired by the second microphone and generates a first audio signal based on a differential signal indicating a difference between the first and second voltage signals; An integrated circuit device having a semiconductor substrate on which is formed may be mounted. Here, the integrated circuit device may be realized by the configuration described with reference to FIGS.

  The voice input unit 3030 includes a first microphone having a first diaphragm, a second microphone having a second diaphragm, a first voltage signal acquired by the first microphone, A differential signal generation unit that generates a first audio signal based on a differential signal indicating a difference from the second voltage signal acquired by the second microphone, and the first and second diaphragms are The noise intensity ratio indicating the ratio of the intensity of the noise component included in the difference signal to the intensity of the noise component included in the first or second voltage signal is the intensity of the input speech component included in the difference signal. The input sound intensity ratio indicating the ratio of the input sound component included in the first or second voltage signal to the intensity may be smaller than the input sound intensity ratio. Here, the voice input unit 3030 may be realized by the configuration described with reference to FIGS.

  The voice input unit 3030 may be configured as a hands-free type that generates the first voice signal based on an input from a microphone.

  An audio output unit 3040 detects an ambient noise during a call based on the first audio signal 3034, and a volume for controlling the volume of the speaker 3046 based on the detected ambient noise level. You may comprise so that the control part 3044 may be included.

  The audio output unit 3040 and the audio input unit 2030 may be separately installed.

  According to the present embodiment, even when used in a noisy environment, the volume of the speaker is controlled continuously or stepwise in accordance with the intensity of ambient noise obtained from the microphone for voice input, so that the voice input person can It is possible to provide a voice / sound input / output device that makes it easy to hear the output sound, for example, in the case of a telephone call, which facilitates transmission and reception.

  In addition, the microphone has a characteristic of easily and extremely effectively suppressing an impact sound that acts directly or indirectly on the device. That is, not only the sound propagating in the air but also the sound propagating in the solid can be removed. Since the propagation speed of sound in a solid is extremely high (about 10 times) compared to the propagation speed in air, the impact sound (noise) applied to the solid on which the microphone is installed reaches the vibrating membrane almost simultaneously. Therefore, it can be removed in the same manner as noise propagating in the air.

  Therefore, it was a very unpleasant phenomenon in the past: “Echo phenomenon where sound emitted from the speaker propagates through the device's enclosure or solid body to the microphone and then returns to the other party as a voice echo” Can be effectively removed.

  Further, since it is excellent in the performance of suppressing howling generated between the microphone and the speaker, it is possible to provide a high-performance hands-free loudspeaker device by incorporating it in a hands-free telephone set on a table, for example.

  Therefore, according to the present embodiment, it is excellent in noise suppression performance against impact noise that directly or indirectly acts on the microphone. It is possible to provide a device having excellent performance even under impact noise that is difficult to remove.

  The same effect can be obtained by incorporating it into a keyboard of a personal computer, a working robot, a digital recorder, a hearing aid, or the like.

  In addition, since it is excellent in the howling suppression performance generated between the microphone and the speaker, it is possible to provide a new voice input / output device resistant to a noise environment.

  Call device 3020 according to the present embodiment is transmitted from voice input / output device 3010, transmission unit 3050 that transmits first voice signal 3034 generated by voice input unit 3030 to the other party's device, and the other party's device. Receiving unit 3060 for receiving second audio signal 3048.

  In addition, this invention is not limited to the above-mentioned embodiment, A various deformation | transformation is possible. The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

The figure for demonstrating a microphone unit. The figure for demonstrating a microphone unit. The figure for demonstrating a microphone unit. The figure for demonstrating a microphone unit. The figure for demonstrating the attenuation | damping property of a sound wave. The figure which shows an example of the data showing the correspondence of a phase difference and an intensity ratio. The flowchart figure which shows the procedure which manufactures a microphone unit. The figure for demonstrating an audio | voice input apparatus. The figure for demonstrating an audio | voice input apparatus. The figure which shows the mobile telephone as an example of a voice input device. The figure which shows the microphone as an example of an audio | voice input apparatus. The figure which shows the remote controller as an example of an audio | voice input apparatus. 1 is a schematic diagram of an information processing system. The figure for demonstrating the microphone unit which concerns on a modification. The figure for demonstrating the microphone unit which concerns on a modification. The figure for demonstrating the microphone unit which concerns on a modification. The figure for demonstrating the microphone unit which concerns on a modification. The figure for demonstrating the microphone unit which concerns on a modification. The figure for demonstrating the microphone unit which concerns on a modification. The figure for demonstrating the microphone unit which concerns on a modification. The figure for demonstrating the microphone unit which concerns on a modification. 4A and 4B illustrate an integrated circuit device. 4A and 4B illustrate an integrated circuit device. 4A and 4B illustrate an integrated circuit device. 4A and 4B illustrate a voice input device including an integrated circuit device. 4A and 4B illustrate a voice input device including an integrated circuit device. The figure for demonstrating the integrated circuit device which concerns on a modification. The figure for demonstrating the voice input device which has the integrated circuit device which concerns on a modification. 1 is a diagram showing a mobile phone as an example of a voice input device having an integrated circuit device. The figure which shows the microphone as an example of the audio | voice input apparatus which has an integrated circuit device. The figure which shows the remote controller as an example of the audio | voice input apparatus which has an integrated circuit device. 1 is a schematic diagram of an information processing system. The figure for demonstrating an audio | voice input apparatus. The figure for demonstrating an audio | voice input apparatus. The figure for demonstrating an audio | voice input apparatus. The figure for demonstrating an audio | voice input apparatus. The figure for demonstrating an audio | voice input apparatus. The functional block diagram of a voice input / output device and a communication device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Microphone unit, 2 ... Voice input device, 3 ... Microphone unit, 4 ... Microphone unit, 5 ... Microphone unit, 6 ... Microphone unit, 7 ... Microphone unit, 8 ... Microphone unit, 9 ... Microphone unit, 10 ... Housing DESCRIPTION OF SYMBOLS 11 ... Housing | casing 12 ... 1st through-hole, 13 ... Microphone unit, 14 ... 2nd through-hole, 16 ... Convex curved surface, 17 ... Concave curved surface, 18 ... Spherical surface, 20 ... Partition member, 21 ... Partition member , 30 ... Vibration membrane, 31 ... Vibration membrane, 32 ... Holding part, 40 ... Electric signal output circuit, 41 ... Vibration membrane unit, 42 ... Capacitor, 44 ... Signal amplification circuit, 45 ... Gain adjustment circuit, 46 ... Charge-up circuit , 48 ... operational amplifier, 50 ... housing, 52 ... opening, 54 ... elastic body, 60 ... arithmetic processing unit, 70 ... Communication processing unit 80 ... vibrating membrane 100 ... internal space 101 ... internal space 102 ... first space 104 ... second space 112 ... first space 114 ... second space 110 ... outside Space, 112 ... first space, 114 ... second space, 122 ... first space, 124 ... second space, 132 ... first space, 134 ... second space, 200 ... condenser microphone, 202 ... Vibration membrane, 204 ... Electrode, 300 ... Mobile phone, 400 ... Microphone, 500 ... Remote controller, 600 ... Information processing system, 602 ... Voice input device, 604 ... Host computer, 1001 ... Integrated circuit device, 1002 ... Voice input Device 1003 Integrated circuit device 1004 Voice input device 1010 First microphone 1012 First vibration membrane 1014 First electrode 101 1st diaphragm, 1016 ... Integrated circuit, 1020 ... 2nd microphone, 1022 ... 2nd diaphragm, 1024 ... 2nd electrode, 1025 ... 2nd diaphragm, 1030 ... Differential signal generation circuit, 1040 ... Case, 1042 ... Opening, 1050 ... Arithmetic processing unit, 1060 ... Communication processing unit, 1100 ... Semiconductor substrate, 1102 ... First recess, 1104 ... Second recess, 1200 ... Semiconductor substrate, 1201 ... First surface DESCRIPTION OF SYMBOLS 1202 ... 2nd surface, 1210 ... 1st recessed part, 1212 ... Opening, 1220 ... 2nd recessed part, 1300 ... Mobile phone, 1400 ... Microphone, 1500 ... Remote controller, 1600 ... Information processing system, 1602 ... Voice input Apparatus 1604 ... host computer 2001 ... voice input device 2010 ... first microphone 2012 ... first diaphragm 20 DESCRIPTION OF SYMBOLS 0 ... 2nd microphone, 2022 ... 2nd diaphragm, 2030 ... Difference signal generation part, 2040 ... Case, 2050 ... Arithmetic processing part, 2060 ... Communication processing part, 2070 ... Base part, 2072 ... Main surface, 2074 ... Recess, 2075 ... Bottom, 2076 ... Region, 2078 ... Opening, 2080 ... Base, 2082 ... Main surface, 2084 ... First recess, 2085 ... First opening, 2086 ... Second recess, 2087 ... Second opening DESCRIPTION OF SYMBOLS 2100 ... Capacitor type microphone, 20102 ... Vibration membrane, 2104 ... Electrode, 3010 ... Voice input / output device, 3020 ... Communication device, 3030 ... Voice input part, 3032 ... Microphone, 3034 ... First voice signal, 3040 ... Voice output , 3042 ... Ambient noise detection unit, 3044 ... Volume control unit, 3046 ... Speaker, 3050 ... Transmission unit, 3060 ... Reception Nobube

Claims (7)

An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A housing having an internal space, a partition member provided in the housing, which divides the internal space into a first space and a second space, at least a part of which is made of a vibrating membrane; and the vibration An electrical signal output circuit that outputs an electrical signal that is a first audio signal based on the vibration of the membrane, and the first space and the external space of the housing are formed on the same surface of the housing. A first through hole that communicates with the second space and a second through hole that communicates between the second space and the external space of the housing are formed, and the vibration membrane is the first through hole when viewed from the normal direction of the surface. located between the first through hole and the second through-hole, the first through the through holes and the distance to the vibrating film and the second through hole Ri distance and the Do different to the vibration film from, The distance from the first through hole to the first surface of the diaphragm, and from the first through hole to the second through hole. Distance is approximately equal microphone unit is mounted,
The audio output unit
An ambient noise detector for detecting ambient noise during a call based on the first audio signal;
A voice input / output device comprising: a volume control unit that controls the volume of the speaker based on the detected magnitude of ambient noise. A hands-free type audio input unit that generates a first audio signal based on an input from a microphone;
A hands-free type voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A housing having an internal space, and the internal space provided in the housing is divided into a first space and a second space
A partition member that is divided into at least a part of a diaphragm, and an electrical signal output circuit that outputs an electrical signal that is a first audio signal based on the vibration of the diaphragm, A first through hole that communicates the first space and the external space of the housing with the same surface of the housing, and a second that communicates the second space and the external space of the housing. And the vibrating membrane is located between the first through hole and the second through hole when viewed from the normal direction of the surface, and the vibration is transmitted from the first through hole. Ri to distance and are Do different distance from the second through hole to said vibration film membrane, the distance from the first through-hole to the first surface of the vibrating membrane, from the first through hole speech, characterized in that the distance to the second through-holes is substantially equal microphone unit is mounted Output device. An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A housing having an internal space, a partition member provided in the housing, which divides the internal space into a first space and a second space, at least a part of which is made of a vibrating membrane; and the vibration An electrical signal output circuit that outputs an electrical signal that is a first audio signal based on the vibration of the membrane, and the first space and the external space of the housing are formed on the same surface of the housing. A first through hole that communicates with the second space and a second through hole that communicates between the second space and the external space of the housing are formed, and the vibration membrane is the first through hole when viewed from the normal direction of the surface. located between the first through hole and the second through-hole, the first through the through holes and the distance to the vibrating film and the second through hole Ri distance and the Do different to the vibration film from, The distance from the first through hole to the first surface of the diaphragm, and from the first through hole to the second through hole. Distance is approximately equal microphone unit is mounted,
The voice input / output apparatus, wherein the voice output unit and the voice input unit are installed separately. An audio input unit that generates a first audio signal based on an input from a microphone;
A voice input / output device including a voice output unit that outputs voice from a speaker based on a second voice signal,
The voice input unit
A housing having an internal space, a partition member provided in the housing, which divides the internal space into a first space and a second space, at least a part of which is made of a vibrating membrane; and the vibration An electrical signal output circuit that outputs an electrical signal that is a first audio signal based on the vibration of the membrane, and the first space and the external space of the housing are formed on the same surface of the housing. A first through hole that communicates with the second space and a second through hole that communicates between the second space and the external space of the housing are formed, and the vibration membrane is the first through hole when viewed from the normal direction of the surface. is disposed between the first through hole and the second through-hole, the first through the through holes and the distance to the vibrating film and the second through hole Ri said Do different and the distance to the vibration film from, The distance from the first through hole to the first surface of the diaphragm, and the second through hole from the first through hole Audio input and output device, characterized in that approximately equal microphone unit distance is in is implemented. The voice input / output device according to claim 4,
The audio output unit
An audio input / output apparatus comprising: a volume control unit that controls the volume of the speaker based on the first audio signal . The voice input / output device according to any one of claims 1 to 5,
The voice input / output device according to claim 1, wherein the vibration film is disposed on a side of the second through hole when viewed from a normal direction of the surface. The voice input / output device according to any one of claims 1 to 6,
A transmission unit for transmitting the first audio signal generated by the audio input unit to the device of the other party;
And a receiver that receives a second audio signal transmitted from the device of the other party.

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