KR102570630B1 - Proximity sensor for bezel-less type electronic device - Google Patents

Abstract

A proximity sensor for bezel-less electronics is provided. A proximity sensor for a bezel-less electronic device according to an embodiment of the present invention includes a first piezoelectric actuator that converts an electrical signal into sound waves or ultrasonic waves in an audible frequency band and an ultrasonic band and functions as a speaker or an ultrasonic transmitter; and a second piezoelectric actuator that converts sound waves or ultrasonic waves into electrical signals in the audible frequency band and ultrasonic band and functions as a microphone or ultrasonic receiver. Here, the ultrasonic transmitter transmits ultrasonic waves toward the user, and the ultrasonic receiver receives ultrasonic waves reflected by the user among the transmitted ultrasonic waves.

Description

Proximity sensor for bezel-less type electronic device}

The present invention relates to a proximity sensor, and more particularly, to a proximity sensor for a bezel-less electronic device.

Recently, electronic devices such as smart phones are configured as bezel-less to maximize a front display area. At this time, research on piezoelectric speakers and linear actuators as receivers is being actively conducted according to the full display of electronic devices, and hybridization for configuration of more improved sound quality is also being actively studied.

In such a bezel-less electronic device, as a hole for a receiver is omitted on the front side, a new method is required for the location or implementation method of the proximity sensor disposed on the front side.

KR 2017-0142571 A (2017.12.28 open)

The present invention has been devised in consideration of the above points, and an object of the present invention is to provide a proximity sensor for a bezel-less electronic device capable of combining speaker and microphone functions and proximity sensor functions using a piezoelectric actuator.

In order to solve the above problems, the present invention provides a proximity sensor for a bezel-less electronic device including a first piezoelectric actuator and a second piezoelectric actuator. The first piezoelectric actuator converts electrical signals into sound waves or ultrasonic waves in an audible frequency band and an ultrasonic band, and functions as a speaker and an ultrasonic transmitter. The second piezoelectric actuator functions as a microphone and an ultrasonic receiver by converting sound waves or ultrasonic waves into electrical signals in an audible frequency band and an ultrasonic band. Here, the ultrasonic transmitter transmits ultrasonic waves, and the ultrasonic receiver receives ultrasonic waves reflected by a user among the transmitted ultrasonic waves.

According to a preferred embodiment of the present invention, the first piezoelectric actuator and the second piezoelectric actuator can be independently driven with respect to the sound wave and the ultrasonic wave by time division processing.

Here, the first piezoelectric actuator includes a first piezoelectric element; and a first electrode and a second electrode respectively provided on both sides of the first piezoelectric element. In this case, the first piezoelectric actuator may further include an auxiliary vibrating body disposed on one side of one of the first electrode and the second electrode.

In addition, the second piezoelectric actuator may include a second piezoelectric element; and a third electrode and a fourth electrode respectively provided on both sides of the second piezoelectric element.

In addition, the first piezoelectric actuator may include a first spacer having one side provided on one side of one of the first electrode and the second electrode; a fifth electrode having one side provided on the other side of the first spacer; a third piezoelectric element having one side disposed on the other side of the fifth electrode; and a sixth electrode provided on the other side of the third piezoelectric element.

In addition, the second piezoelectric actuator may include a second spacer having one side provided on one side of one of the third electrode and the fourth electrode; a seventh electrode, one side of which is provided on the other side of the second spacer; a fourth piezoelectric element having one side disposed on the other side of the seventh electrode; and an eighth electrode provided on the other side of the fourth piezoelectric element.

According to the present invention, the first piezoelectric actuator is provided for both a speaker and an ultrasonic transmitter, and the second piezoelectric actuator is provided for both a microphone and an ultrasonic receiver, so that a bezel-less electronic device is provided without a separate proximity sensor. Since a proximity sensor can be implemented using a speaker and a microphone, it is possible to reduce the space in which components are mounted in a bezel-less electronic device.

In addition, the present invention drives the first piezoelectric actuator and the second piezoelectric actuator in the audio frequency band and the ultrasonic band through time-division processing, thereby minimizing the mounting space of components in a bezel-less electronic device because a proximity sensor is not separately provided. At the same time, you can save money.

In addition, the present invention provides a separate piezoelectric element for independently driving the first piezoelectric actuator and the second piezoelectric actuator in the audio frequency band and the ultrasonic band, thereby eliminating interference between the speaker and microphone function and proximity sensor function. .

1 is a perspective view showing a bezel-less electronic device for applying a proximity sensor according to an embodiment of the present invention;
2 is a schematic layout diagram of a proximity sensor for a bezel-less electronic device according to an embodiment of the present invention;
3 is a diagram for explaining an example in which a proximity sensor for a bezel-less electronic device according to an embodiment of the present invention is used;
4 is a block diagram schematically illustrating an electronic device to which a proximity sensor according to an embodiment of the present invention is applied;
5 is a cross-sectional view showing an example of the first piezoelectric actuator of FIG. 2;
6 is a cross-sectional view showing an example of the second piezoelectric actuator of FIG. 2;
7 is a cross-sectional view showing another example of the first piezoelectric actuator of FIG. 2, and
8 is a cross-sectional view illustrating another example of the second piezoelectric actuator of FIG. 2 .

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. This invention may be embodied in many different forms and is not limited to the embodiments set forth herein. In order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

Hereinafter, a proximity sensor for a bezel-less electronic device according to an embodiment of the present invention will be described with reference to the drawings.

Referring to FIGS. 1 and 2 , a proximity sensor 100 for a bezel-less electronic device includes a first piezoelectric actuator 110 and a second piezoelectric actuator 120 .

The proximity sensor 100 for a bezel-less electronic device may be mounted on a rear surface of the bezel-less electronic device 10 . Here, the first piezoelectric actuator 110 may be used both as a speaker and an ultrasonic transmitter. In addition, the second piezoelectric actuator 120 may be used as both a microphone and an ultrasonic receiver.

Accordingly, in the bezel-less electronic device 10, it is possible to implement a proximity sensor using a speaker and a microphone that are necessarily provided without having a separate proximity sensor. Accordingly, a space in which components are mounted in the bezel-less electronic device 10 may be reduced.

In this case, the first piezoelectric actuator 110 and the second piezoelectric actuator 120 may be mounted on the back frame of the bezel-less electronic device 10 or the rear surface of the display panel, as shown in FIG. 2 . For example, the first piezoelectric actuator 110 may be disposed on one side (upper side in FIG. 2 ) of the back frame of the bezel-less electronic device 10 or the rear surface of the display panel.

In addition, the second piezoelectric actuator 120 may be disposed on the other side (lower side in FIG. 2 ) of the back frame of the bezel-less electronic device 10 or the rear surface of the display panel. Here, the back frame or display panel may have a diaphragm function of the first piezoelectric actuator 110 functioning as a speaker.

Here, the first piezoelectric actuator 110 and the second piezoelectric actuator 120 have sizes optimized for the vibrating body in order to generate sound waves and ultrasonic waves. At this time, it can be attached with an adhesive layer in order to transmit appropriate vibration force with the vibrating object, and it is possible to alleviate and flatten pick-dip of sound waves and ultrasonic waves by having appropriate elasticity and adhesion.

The present invention is to combine a microphone and speaker function and a proximity sensor function by utilizing a piezoelectric actuator. To this end, the first piezoelectric actuator 110 converts electrical signals into sound waves or ultrasonic waves in the audible frequency band and ultrasonic band, and functions as a speaker and an ultrasonic transmitter.

In addition, the second piezoelectric actuator 120 converts sound waves or ultrasonic waves into electric signals in the audible frequency band and ultrasonic band, and functions as a microphone and ultrasonic receiver.

Referring to FIG. 3 , in the ultrasonic band, the first piezoelectric actuator 110 is an ultrasonic transmitter and transmits ultrasonic waves toward the user. At this time, the second piezoelectric actuator 120 is an ultrasonic receiver and receives ultrasonic waves reflected by the user's face 1 among ultrasonic waves transmitted by the first piezoelectric actuator 110 .

Also, in the sound wave band, the first piezoelectric actuator 110 is a speaker, and can output sound waves so that the user can hear them through ears. At this time, the second piezoelectric actuator 120 is a microphone and can receive sound waves so that the user can communicate through the mouth.

Referring to FIG. 4 , the first piezoelectric actuator 110 and the second piezoelectric actuator 120 are subjected to time-division processing through the time-division processor 11, so that they can be independently driven with respect to sound waves and ultrasonic waves.

For example, the time division processing unit 11 may interlock the sound control unit 12 and the proximity sensor control unit 13 with the proximity sensor 100 for a bezel-less electronic device for each of a sound wave for a call and an ultrasonic wave for proximity sensing. .

That is, when the proximity sensor 100 for a bezel-less electronic device functions as a proximity sensor, the time division processor 11 may interlock the proximity sensor controller 13 with the proximity sensor 100 for a bezel-less electronic device.

At this time, the first piezoelectric actuator 110 may transmit an ultrasonic signal under the control of the proximity sensor controller 13 . The second piezoelectric actuator 120 may receive an ultrasonic signal under the control of the proximity sensor controller 13 . Here, the proximity sensor controller 13 may determine whether the user is close by using a difference between the transmission time of the ultrasonic wave and the reception time of the ultrasonic wave.

In addition, when the proximity sensor 100 for a bezel-less electronic device functions as a microphone and a speaker, the time division processing unit 11 may interlock the sound controller 12 and the proximity sensor 100 for a bezel-less electronic device.

At this time, the first piezoelectric actuator 110 may output sound waves corresponding to the audio function of the electronic device 10 under the control of the sound controller 12 . The second piezoelectric actuator 120 may receive a sound wave corresponding to a user's voice or ambient sound under the control of the sound controller 12 .

Accordingly, since the proximity sensor 100 for a bezel-less electronic device is not separately provided for the proximity sensor, a mounting space for parts in the bezel-less electronic device 10 can be minimized and costs can be reduced.

Referring to FIG. 5 , the first piezoelectric actuator 110 may include a first piezoelectric element 111 , a first electrode 112 and a second electrode 114 .

The first piezoelectric element 111 may vibrate according to electrical signals applied to the first electrode 112 and the second electrode 114 to output ultrasonic waves. At this time, the electrical signal applied to the first piezoelectric element 111 may be an ultrasonic oscillation signal provided from the proximity sensor controller 13 .

In addition, the first piezoelectric element 111 may be driven in an audible frequency band lower than the ultrasonic band. At this time, the first piezoelectric element 111 may vibrate according to a sound control signal output from the sound controller 12 in the electronic device 10 having an audio function to output sound waves in an audible frequency band.

The first electrode 112 may be disposed above the first piezoelectric element 111 , and the second electrode 114 may be disposed below the first piezoelectric element 111 . Here, the positions where the first electrode 112 and the second electrode 114 are formed on the first piezoelectric element 111 are only described with reference to FIG. 5 and are not particularly limited.

In addition, the first piezoelectric actuator 110 may further include an auxiliary vibrator 116 . Here, the auxiliary vibrator 116 may be disposed on one side of either the first electrode 112 or the second electrode 114 . For example, the auxiliary vibrator 116 may be disposed above the first electrode 112 . Accordingly, the first piezoelectric actuator 110 can improve a characteristic of converting an electrical signal into a sound wave.

Referring to FIG. 6 , the second piezoelectric actuator 120 may include a second piezoelectric element 121 , a third electrode 122 and a fourth electrode 124 .

The second piezoelectric element 121 may output an electrical signal according to input ultrasonic vibration. At this time, the second piezoelectric element 121 has a function of detecting ultrasonic vibration reflected by an object such as a user and outputting a corresponding electrical signal.

In addition, the second piezoelectric element 121 may receive sound wave vibration in an audible frequency band lower than the ultrasonic band. At this time, the second piezoelectric element 121 has a function of detecting vibration caused by a user's voice or ambient sound and outputting a corresponding electrical signal.

The third electrode 122 may be disposed above the second piezoelectric element 121 , and the fourth electrode 124 may be disposed below the second piezoelectric element 121 . Here, the positions where the third electrode 122 and the fourth electrode 124 are formed on the second piezoelectric element 121 are only described with reference to FIG. 6 and are not particularly limited.

Meanwhile, in the proximity sensor 100 for a bezel-less electronic device according to an embodiment of the present invention, the first piezoelectric actuator 110 and the second piezoelectric actuator 120 are independently driven for each of the ultrasonic band and the audio frequency band. It can be composed of a double structure. That is, the first piezoelectric actuator 110 and the second piezoelectric actuator 120 may include separate piezoelectric elements to output structurally independent signals for each of the ultrasonic band and the audio frequency band.

Accordingly, the efficiency and characteristics of each function can be improved by eliminating interference between the speaker/microphone function and the proximity sensor function. In particular, each of the speaker and microphone functions and proximity sensor functions can be optimized through maximization of reception performance.

Referring to FIG. 7 , the first piezoelectric actuator 210 includes a third piezoelectric element 215 and a fifth electrode 216 in addition to the first piezoelectric element 111, the first electrode 112, and the second electrode 114. ), a sixth electrode 218 and a first spacer 119 may be further included.

At this time, the first piezoelectric element 111, the first electrode 112, and the second electrode 114 are the first functional units, and the third piezoelectric element 215, the fifth electrode 216, and the sixth electrode 218 ) may be the second functional unit. For example, the first functional unit may be an ultrasonic transmitter and the second functional unit may be a speaker or vice versa.

Since the first functional unit is the same as that of FIG. 5 , details are omitted here. Similar to the first functional unit, the second functional unit may include a fifth electrode 216 and a sixth electrode 218 on both sides of the third piezoelectric element 215 .

Here, the first piezoelectric element 111 and the third piezoelectric element 215 may be independently driven in an ultrasonic band or an audible frequency band according to their functions.

In this embodiment, the first functional unit is shown and described as being disposed on the upper side and the second functional unit is disposed on the lower side, but is not limited thereto and may be stacked on the contrary.

The first spacer 119 may be disposed between the first functional unit and the second functional unit. The first spacer 119 serves to independently drive the first function unit and the second function unit. That is, the first spacer 119 may have a function of preventing vibrations output from the first function unit and vibrations output from the second function unit from interfering with each other. For example, the first spacer 119 may be a vibration absorber, but is not limited thereto.

Referring to FIG. 8 , the second piezoelectric actuator 220 includes a fourth piezoelectric element 225 and a seventh electrode 226 in addition to the second piezoelectric element 121, the third electrode 122, and the fourth electrode 124. ), an eighth electrode 228 and a second spacer 219 may be further included.

At this time, the second piezoelectric element 121, the third electrode 122, and the fourth electrode 124 are the third functional units, and the fourth piezoelectric element 225, the seventh electrode 226, and the eighth electrode 228 ) may be the fourth functional unit. For example, the third functional unit may be an ultrasonic receiving unit and the fourth functional unit may be a microphone or vice versa.

Since the third functional unit is the same as that of FIG. 6 , detailed description thereof is omitted. Similar to the third functional unit, the fourth functional unit may include a seventh electrode 226 and an eighth electrode 228 on both sides of the fourth piezoelectric element 225 .

Here, the second piezoelectric element 121 and the fourth piezoelectric element 225 may be independently driven in an ultrasonic band or an audible frequency band according to their functions.

In this embodiment, the third functional unit is shown and described as being disposed on the upper side and the fourth functional unit is disposed on the lower side, but is not limited thereto and may be stacked on the contrary.

The second spacer 219 may be disposed between the third and fourth functional units. The second spacer 219 serves to independently drive the third and fourth functional units. That is, the second spacer 219 may have a function of preventing vibrations detected by the third function unit and vibrations detected by the fourth function unit from interfering with each other. For example, the second spacer 219 may be a vibration absorber, but is not limited thereto.

Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiments presented herein, and those skilled in the art who understand the spirit of the present invention may add elements within the scope of the same spirit. However, other embodiments can be easily proposed by means of changes, deletions, additions, etc., but these will also fall within the scope of the present invention.

100: proximity sensor for bezel-less electronics
110,210: first piezoelectric actuator 111: first piezoelectric element
112: first electrode 114: second electrode
116: auxiliary vibrating body 120,220: second piezoelectric actuator
121: second piezoelectric element 122: third electrode
124: fourth electrode 215: third piezoelectric element
216: fifth electrode 218: sixth electrode
219: first spacer 225: fourth piezoelectric element
226: 7th electrode 228: 8th electrode
229: second separation part

Claims (7)

As a proximity sensor that is applied to a bezel-less electronic device that includes a display on the front but omits a hole for a receiver for sound waves and ultrasonic waves from the front, and performs both a speaker function, a microphone function, and a proximity sensor function. ,
a first piezoelectric actuator that performs both the speaker function of converting an audio frequency band into sound waves and the ultrasonic transmitter function of converting an ultrasonic wave into ultrasonic waves; and
A second piezoelectric actuator that simultaneously performs the function of the microphone for converting sound waves in the audible frequency band into electrical signals and the function of an ultrasonic receiver for converting ultrasonic waves in the ultrasonic band into electrical signals,
The first piezoelectric actuator transmits ultrasonic waves according to the function of the ultrasonic transmitter and the second piezoelectric actuator receives ultrasonic waves reflected by a user among the transmitted ultrasonic waves according to the function of the ultrasonic receiver, thereby performing the function of the proximity sensor Proximity sensor for bezel-less electronics. According to claim 1,
The first piezoelectric actuator and the second piezoelectric actuator separately process the sound wave and the ultrasonic wave according to time division processing, thereby independently processing the sound wave and the ultrasonic wave. Proximity sensor for devices. The method of claim 1, wherein the first piezoelectric actuator,
a first piezoelectric element; and
A proximity sensor for a bezel-less electronic device including a first electrode and a second electrode provided on both sides of the first piezoelectric element, respectively. According to claim 3,
The first piezoelectric actuator further comprises an auxiliary vibrating body disposed on one side of one of the first electrode and the second electrode. The method of claim 1, wherein the second piezoelectric actuator,
a second piezoelectric element; and
A proximity sensor for a bezel-less electronic device including a third electrode and a fourth electrode provided on both sides of the second piezoelectric element, respectively. According to claim 3,
The first piezoelectric actuator and the second piezoelectric actuator include a dual structure in which a structure for processing the sound wave and a structure for processing the ultrasonic wave are implemented independently, respectively;
The first piezoelectric actuator,
a first spacer having one side provided on one side of either the first electrode or the second electrode;
a fifth electrode having one side provided on the other side of the first spacer;
a third piezoelectric element having one side disposed on the other side of the fifth electrode; and
Further comprising a sixth electrode provided on the other side of the third piezoelectric element,
In the first piezoelectric actuator, the first electrode, the second electrode, and the first piezoelectric element are included in a structure for processing the sound wave, and the fifth electrode, the sixth electrode, and the third piezoelectric element are Proximity sensor for bezel-less electronics embedded in a structure that processes ultrasonic waves. According to claim 5,
The first piezoelectric actuator and the second piezoelectric actuator include a dual structure in which a structure for processing the sound wave and a structure for processing the ultrasonic wave are implemented independently, respectively;
The second piezoelectric actuator,
a second spacer having one side provided on one side of one of the third electrode and the fourth electrode;
a seventh electrode, one side of which is provided on the other side of the second spacer;
a fourth piezoelectric element having one side disposed on the other side of the seventh electrode; and
Further comprising an eighth electrode provided on the other side of the fourth piezoelectric element,
In the second piezoelectric actuator, the third electrode, the fourth electrode, and the second piezoelectric element are included in a structure for processing the sound wave, and the seventh electrode, the eighth electrode, and the fourth piezoelectric element are Proximity sensor for bezel-less electronics embedded in a structure that processes ultrasonic waves.

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