JP2014062796A - Information acquisition device and object detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information acquisition device capable of improving the accuracy of distance detection by suppressing the influence of disturbance light and to provide an object detector in which the information acquisition device is mounted.SOLUTION: The information acquisition device 1 includes a projection optical system 11 projecting light of a predetermined dot pattern to a target area and a light-receiving optical system 12 arranged in parallel with the projection optical system 11 separated by a predetermined distance and imaging the target area. A laser light source 111 includes two light-emitting parts 111a and 111b having different emission wavelength bands. A laser control part 21a holds a predetermined switching condition 25a for switching the light-emitting parts used for measurement from one light-emitting part to the other light-emitting part and determines the light-emitting part used for measurement in the light-emitting parts 111a and 111b, based on the switching condition 25a.

Description

  The present invention relates to an object detection apparatus that detects an object in a target area based on the state of reflected light when light is projected onto the target area, and an information acquisition apparatus suitable for use in the object detection apparatus.

  Conventionally, object detection devices using light have been developed in various fields. An object detection apparatus using a so-called distance image sensor as an information acquisition apparatus can detect not only a planar image on a two-dimensional plane but also the shape and movement of the detection target object in the depth direction. In such an object detection device, light in a predetermined wavelength band is projected from a laser light source or LED (Light Emitting Diode) onto a target area, and the reflected light is received (imaged) by a light receiving element such as a CMOS image sensor. . Various types of information acquisition devices are known.

  In an information acquisition apparatus of a type that irradiates a target area with laser light having a predetermined dot pattern, reflected light from the target area of laser light having a dot pattern is received by a light receiving element. Based on the light receiving position of the dot on the light receiving element, the distance to each part of the detection target object (irradiation position of each dot on the detection target object) is detected using triangulation (for example, non-patent) Reference 1).

19th Annual Conference of the Robotics Society of Japan (September 18-20, 2001) Proceedings, P1279-1280

  In the information acquisition apparatus having the above configuration, a narrow band pass filter that transmits only light in the wavelength band of the laser beam is used to guide the reflected light from the target region of the laser beam having the dot pattern to the light receiving element. . On the other hand, the temperature of the laser light source varies depending on the usage environment surrounding the laser light source, such as the temperature around the laser light source. In order to cope with such wavelength fluctuations, it is necessary to set a wide transmission wavelength band of the bandpass filter in advance.

  However, when the transmission wavelength band of the bandpass filter is widened, disturbance light that is light other than the reflected light from the target region of the laser light having the dot pattern is also transmitted to the light receiving element through the bandpass filter. . Thus, if the amount of ambient light received is increased, the accuracy of distance detection may be reduced.

  The present invention has been made to solve such problems, and an object of the present invention is to provide an information acquisition device and an object detection device capable of suppressing the influence of ambient light and improving the accuracy of distance detection. And

A 1st aspect of this invention is related with the information acquisition apparatus which acquires the information of a target area | region using light. The information acquisition apparatus according to the present aspect projects a laser light source including a plurality of light emitting units that emit laser beams having different wavelengths, and projects the laser light emitted from the laser light source onto a target region with a predetermined dot pattern. A projection optical system; and a filter disposed in one direction with respect to the projection optical system, the filter configured to transmit the reflected light reflected from the target area, and receiving the reflected light transmitted through the filter Based on a light receiving optical system that images the target area with an image sensor and an actual image including the dot pattern captured by the image sensor at the time of actual measurement, distance information related to a distance to an object included in the target area is acquired. A distance acquisition unit that controls the laser light source, and a laser control unit that controls the laser light source. The laser control unit holds a predetermined switching condition for switching a light emitting unit used for measurement from one light emitting unit to another light emitting unit among the plurality of light emitting units due to a change in an emission wavelength band based on a temperature change, Based on the switching condition, a light emitting unit used for measurement is determined among the plurality of light emitting units.

  A 2nd aspect of this invention is related with an object detection apparatus. The object detection apparatus according to this aspect includes the information acquisition apparatus according to the first aspect.

  ADVANTAGE OF THE INVENTION According to this invention, the information acquisition apparatus which can suppress the influence of disturbance light and can raise the precision of distance detection, and an object detection apparatus carrying this can be provided.

  The features of the present invention will become more apparent from the following description of embodiments. However, the following embodiment is merely one embodiment of the present invention, and the meaning of the term of the present invention or each constituent element is not limited to that described in the following embodiment. Absent.

It is a figure which shows the structure of the object detection apparatus which concerns on embodiment. It is a figure which shows the structure of the information acquisition apparatus and information processing apparatus which concern on embodiment. It is a figure which shows the irradiation state of the laser beam with respect to the target area | region which concerns on embodiment, and the light reception state of the laser beam on an image sensor. It is a figure explaining the distance detection method which concerns on this Embodiment. It is a perspective view which shows the external appearance of the projection optical system which concerns on embodiment, and a light-receiving optical system. It is a side view which shows the structure of the projection optical system and light reception optical system which concern on embodiment, the figure which shows typically the state of the laser beam which permeate | transmitted DOE, and the figure which shows the structure of a laser light source typically. It is a figure which shows typically the shift condition of a dot pattern when the light emission part which concerns on embodiment is switched. It is a figure which shows the relationship between the emission wavelength band and temperature of two light emission parts which concern on embodiment. It is a flowchart which shows lighting control of the two light emission parts which concern on embodiment. It is a side view which shows the structure of the projection optical system which concerns on the example of a change, and the structure of a light reception optical system, and a figure which shows typically the shift condition of a dot pattern when the light emission part is switched. It is a figure which shows typically the dot matching condition when the dot pattern which concerns on the said modification is shifted. It is a flowchart which shows the lighting control of the light emission part which concerns on the other example of a change. It is a figure which shows the oscillation characteristic of the light emission part which concerns on the example of another change, and the structure of a laser light source. It is a figure which shows the content of the flowchart and switching condition which show the lighting control of the light emission part which concerns on the example of a change shown in FIG.

  Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, an information acquisition device of a type that irradiates a target area with laser light having a predetermined dot pattern is exemplified.

In the present embodiment, the DOE 114 corresponds to a “diffractive optical element” recited in the claims. The distance calculation unit 21b corresponds to a “distance acquisition unit” recited in the claims. However, these correspondences are merely examples, and the scope of the claims is not limited to the embodiments.

  First, FIG. 1 shows a schematic configuration of the object detection apparatus according to the present embodiment. As shown in FIG. 1, the object detection device includes an information acquisition device 1 and an information processing device 2. The television 3 is controlled by a signal from the information processing device 2.

  The information acquisition device 1 projects infrared light over the entire target area and receives the reflected light with a CMOS image sensor, whereby the distance between each part of the object in the target area (hereinafter referred to as “three-dimensional distance information”). To get. The acquired three-dimensional distance information is sent to the information processing apparatus 2 via the cable 4.

  The information processing apparatus 2 is, for example, a television control controller, a game machine, a personal computer, or the like. The information processing device 2 detects an object in the target area based on the three-dimensional distance information received from the information acquisition device 1, and controls the television 3 based on the detection result.

  FIG. 2 shows a schematic configuration of the object detection apparatus according to the present embodiment. In FIG. 2, XYZ axes orthogonal to each other are attached for the sake of convenience in order to indicate directions related to the projection optical system 11 and the light receiving optical system 12.

  The information acquisition apparatus 1 includes a projection optical system 11 and a light receiving optical system 12 as a configuration of an optical unit. The projection optical system 11 and the light receiving optical system 12 are arranged in the information acquisition device 1 so as to be aligned in the X-axis direction.

The projection optical system 11 includes a laser light source 111, a collimator lens 112, a reflection mirror 113, and a diffractive optical element (DOE) 114.
The light receiving optical system 12 includes a filter 121, an aperture 122, an imaging lens 123, and a CMOS image sensor 124. In addition, the information acquisition apparatus 1 includes a CPU (Central Processing Unit) 21, a laser drive circuit 22, an imaging signal processing circuit 23, an input / output circuit 24, and a memory 25 as a circuit unit.

  Furthermore, the information acquisition device 1 includes a temperature sensor 130 for detecting the temperature of the laser light source 111. The temperature sensor 130 is disposed at a position close to the laser light source 111 in order to detect the temperature around the laser light source 111.

  The laser light source 111 is a so-called frame type semiconductor laser, and outputs a laser beam having a narrow wavelength band in a direction away from the light receiving optical system 12 (X-axis negative direction). In the laser light source 111, two light emitting portions 111a and 111b are arranged so as to be aligned in the X-axis direction. Each of the laser beams emitted from these light emitting portions overlaps each other in a part of its wavelength band at an assumed use environment temperature. The details of the laser light source 111 and the light emitting units 111a and 111b will be described in detail later with reference to FIG. 6C and FIG.

  The collimator lens 112 converts the laser light emitted from the laser light source 111 into light that is slightly wider than parallel light.

  The reflection mirror 113 reflects the laser light incident from the collimator lens 112 side in the direction toward the DOE 114 (Z-axis direction).

The DOE 114 is composed of a plate-like member and is installed so that the emission surface faces the target area. The DOE 114 has a diffraction pattern formed on the incident surface. Due to the diffraction effect of the diffraction pattern, the laser light incident on the DOE 114 is converted into a dot pattern laser light and irradiated onto the target region. The diffraction pattern is, for example, a structure in which a step type diffraction grating is formed in a predetermined pattern. The diffraction grating is adjusted in pattern and pitch so as to convert the laser light transmitted through the collimator lens 112 into a laser light of a dot pattern. Each dot in the dot pattern is a laser beam incident on the DOE 114 separated by a diffraction grating.

  The DOE 114 irradiates the target region with the laser beam incident from the reflection mirror 113 as a laser beam having a dot pattern that spreads radially. The size of each dot in the target area is a size corresponding to the convergence effect of the collimator lens 112. Laser light (0th order light) that is not diffracted by the DOE 114 passes through the DOE 114 and travels straight. The spot size of the 0th-order light in the target area is also in accordance with the convergence effect of the collimator lens 112, as with other dots.

  The laser light reflected from the target area enters the imaging lens 123 via the filter 121 and the aperture 122.

  The filter 121 is a band-pass filter that transmits light in the wavelength band including the emission wavelength of the laser light source 111 and cuts the wavelength band of visible light. The transmission wavelength band of the filter 121 will be described later with reference to FIG.

  The aperture 122 shields the outer periphery of light incident from the outside so as to match the F number of the imaging lens 123. The imaging lens 123 condenses the light incident through the aperture 122 on the CMOS image sensor 124. The imaging lens 123 is composed of a plurality of lenses.

  The CMOS image sensor 124 receives the light collected by the imaging lens 123 and outputs a signal (charge) corresponding to the amount of received light to the imaging signal processing circuit 23 for each pixel. Here, in the CMOS image sensor 124, the output speed of the signal is increased so that the signal (charge) of the pixel can be output to the imaging signal processing circuit 23 with high response from light reception in each pixel.

  The CPU 21 controls each unit according to a control program stored in the memory 25. With this control program, the CPU 21 is provided with the functions of a laser control unit 21a for controlling the laser light source 111 and a distance calculation unit 21b for generating three-dimensional distance information. The memory 25 holds a predetermined switching condition 25a. Based on the switching condition 25a and the temperature detected by the temperature sensor 130, the laser control unit 21a sets one of the light emitting units 111a and 111b as a light emitting unit used for measurement.

  The laser drive circuit 22 drives the laser light source 111 in accordance with a control signal from the CPU 21 (laser control unit 21a).

  The imaging signal processing circuit 23 controls the CMOS image sensor 124 and sequentially takes in the signal (charge) of each pixel generated by the CMOS image sensor 124 for each line. Then, the captured signals are sequentially output to the CPU 21. Based on the signal (imaging signal) supplied from the imaging signal processing circuit 23, the CPU 21 calculates the distance from the information acquisition device 1 to each part of the detection target object through processing by the distance calculation unit 21b. The input / output circuit 24 controls data communication with the information processing apparatus 2.

  The information processing apparatus 2 includes a CPU 31, an input / output circuit 32, and a memory 33.

  The CPU 31 controls each unit according to a control program stored in the memory 33. With such a control program, the CPU 31 is provided with the function of the object detection unit 31a for detecting an object in the image.

  For example, when the control program is a program for controlling the function of the television 3, the object detection unit 31 a detects a person in the image and its movement (gesture) from the three-dimensional distance information supplied from the information acquisition device 1. To do. Then, processing for controlling functions (channel switching, volume adjustment, etc.) of the television 3 is executed by the control program in accordance with the detected movement (gesture).

  The input / output circuit 32 controls data communication with the information acquisition device 1.

  FIG. 3A is a diagram schematically showing the irradiation state of the laser light on the target region, and FIG. 3B is a diagram schematically showing the light receiving state of the laser light in the CMOS image sensor 124. FIG. 3B shows a light receiving state when a flat surface (screen) exists in the target region for convenience.

  From the projection optical system 11, laser light having a dot pattern (hereinafter, the whole laser light having this pattern is referred to as “DP light”) is irradiated onto the target area. In FIG. 3A, the light flux region of DP light is indicated by a solid line frame. In the light flux of DP light, dot regions (hereinafter simply referred to as “dots”) generated by the diffraction action by the DOE 114 are scattered according to the dot pattern by the diffraction action by the DOE 114. As described above, each dot in the dot pattern is obtained by separating the laser light incident on the DOE 114 by the diffraction grating.

  In FIG. 3A, the light beam of DP light is divided into a plurality of segment regions arranged in a matrix for distance detection. Each segment area can be distinguished from other segment areas by a dot-spotted pattern in the segment area. That is, each segment area includes a plurality of dots, and the distribution of dots in the segment area is different from the other segment areas.

  When a flat surface (screen) exists in the target area, the segment areas of DP light reflected thereby are distributed in a matrix on the CMOS image sensor 124 as shown in FIG.

  FIG. 4A is a diagram for explaining a distance detection method according to the present embodiment.

  As shown in FIG. 4A, a flat reflection plane RS perpendicular to the Z-axis is disposed at a predetermined distance Ls from the projection optical system 11. The emitted DP light is reflected by the reflection plane RS and enters the CMOS image sensor 124 of the light receiving optical system 12.

  Hereinafter, an image composed of all pixel values obtained by reflection from the reflection plane RS is referred to as a “reference image”, and the reflection plane RS is referred to as a “reference plane”.

For example, as shown in FIG. 4A, when an object is present at a position closer than the distance Ls, DP light (DPn) corresponding to the segment area Sn on the reference image is reflected by the object, and what is the segment area Sn? It is incident on a different region Sn ′. Since the projection optical system 11 and the light receiving optical system 12 are adjacent to each other in the X-axis direction, the displacement direction of the region Sn ′ with respect to the segment region Sn is parallel to the X-axis. In the case of FIG. 4A, since the object is at a position closer than the distance Ls, the region Sn ′ is displaced in the positive direction of the X axis with respect to the segment region Sn. If the object is at a position farther than the distance Ls, the region Sn ′ is displaced in the negative X-axis direction with respect to the segment region Sn.

  Based on the displacement direction and displacement amount of the region Sn ′ with respect to the segment region Sn, the distance Lr from the projection optical system 11 to the portion of the object irradiated with DP light (the portion corresponding to the segment region Sn) is the distance Ls. And calculated based on triangulation. Similarly, the distance from the projection optical system 11 is calculated for the part of the object corresponding to another segment area. The details of this calculation method are described in, for example, Non-Patent Document 1 (The 19th Annual Conference of the Robotics Society of Japan (September 18-20, 2001) Proceedings, P1279-1280).

  Thus, in order to acquire the three-dimensional distance information, it is necessary to detect the displacement position of the segment region Sn. For this reason, at the time of actual measurement, the dots included in the segment area Sn and the dots included in an image captured at the time of actual measurement (hereinafter referred to as “measurement image”) are collated, and the displacement position of the segment area Sn on the actual measurement image is determined. Explored.

  For example, when searching for the displacement position at the time of actual measurement of the segment area Si shown in FIG. 4B, as shown in FIG. 4C, the area Si0 at the same position as the segment area Si is centered on the actual measurement image. In addition, the range of + α pixels and −α pixels in the X-axis direction is set as the search range L0. At the time of search, the segment area Si is sent in the X-axis direction pixel by pixel in the search range L0, and the dot pattern on the segment area Si is compared with the dot pattern on the measured image at each feed position. Hereinafter, a region corresponding to each feed position on the actually measured image is referred to as a “comparison region”. In the search range L0, comparison areas having the same size as the segment area Si are set every other pixel. The search range L0 is set according to the range of distances to be acquired. The wider the range of distances to be acquired, the wider the search range L0.

  In the search range L0 set in this way, while the segment area Si is fed one pixel at a time in the X-axis direction, the matching degree between the dot pattern of the segment area Si and the dot pattern of the comparison area at each feed position is set at each feed position. Desired. The reason why the segment area Si is sent only in the X-axis direction within the search range L0 is that the dot pattern in the segment area is normally displaced only in the X-axis direction during measurement as described above.

  At the time of detecting the matching degree, the difference between the pixel value of each pixel in the segment area Si and the pixel value of the corresponding pixel in the comparison area is obtained. A value Rsad obtained by adding the obtained difference to all the pixels in the comparison region is acquired as a value indicating the similarity.

  For example, when n columns × m rows of pixels are included in one segment area, the pixel values T (i, j) of the i columns in the segment area, the j rows of pixels, and the i columns in the comparison area, A difference from the pixel value I (i, j) of the pixels in the j row is obtained. Then, a difference is obtained for all the pixels in the segment area, and a value Rsad of the following equation is obtained from the sum of the differences.

The smaller the value Rsad, the higher the degree of similarity between the segment area and the comparison area. Therefore, the comparison area having the minimum obtained value Rsad is detected as the movement area of the segment area Si. Based on the displacement position of the segment region Si thus detected, the three-dimensional distance information is acquired by the triangulation method as described above. Similar processing is performed for the other segment regions.

  FIG. 5 is a perspective view showing an installation state of the projection optical system 11 and the light receiving optical system 12.

  The projection optical system 11 and the light receiving optical system 12 are installed on a base plate 300 having high thermal conductivity. The optical members (laser light source 111, collimator lens 112, reflection mirror 113, DOE 114) constituting the projection optical system 11 are installed on the chassis 11a, and the chassis 11a is installed on the installation surface P1 of the base plate 300. Thereby, the projection optical system 11 is installed on the installation surface P <b> 1 on the base plate 300.

  The laser light source 111 is held by a holder 11b having high thermal conductivity. By attaching the holder 11b to the chassis 11a, the laser light source 111 is installed on the chassis 11a. As described above, the laser light source 111 is composed of a frame type semiconductor laser having a flat shape. When viewed in a direction parallel to the optical axis of the laser beam, the laser light source 111 has a thickness dimension that is several steps smaller than the width dimension. As shown in FIG. 5, the laser light source 111 is arranged so that the thickness direction is parallel or substantially parallel to the Y axis. Here, “substantially parallel” includes a state in which the thickness direction of the laser light source 111 is inclined about 10 degrees around the X axis from a state parallel to the Y axis.

  2 is disposed so as to be close to the holder 11b.

  The light receiving optical system 12 is installed on the upper surface (installation surface P2) of the two pedestals 300a on the base plate 300 and the upper surface (installation surface P2) of the base plate 300 between the two pedestals 300a. A CMOS image sensor 124 is installed on the upper surface (installation surface P2) of the base plate 300 between the two pedestals 300a, and a filter 121, an aperture 122, and an imaging lens 123 are held on the upper surface (installation surface P2) of the pedestal 300a. A holding plate 12a is installed. The imaging lens 123 and the aperture 122 are held by a lens holder 12b attached to the holding plate 12a, and a filter 121 is attached to the front portion of the lens holder 12b.

  The projection optical system 11 and the light receiving optical system 12 are arranged with a predetermined distance in the X-axis direction. In a space S between the projection optical system 11 and the light receiving optical system 12, a circuit board 200 (see FIG. 6) on which the circuit unit of the information acquisition device 1 shown in FIG.

  FIG. 6A is a diagram schematically showing the configuration of the projection optical system 11 and the light receiving optical system 12 according to the present embodiment.

  As shown in FIG. 6A, in the present embodiment, the laser light source 111, the collimator lens 112, the collimator lens 112, and the reflection mirror 113 are arranged in a straight line, and the DOE 114 faces the target area. The reflection mirror 113 and the DOE 114 are installed on the base plate 300. The optical axes of the laser light source 111 and the collimator lens 112 are bent vertically by the reflection mirror 113 and become parallel to the Z axis.

  The configuration in which the optical components constituting the projection optical system 11 are installed on the base plate 300 is an example of the configuration according to claim 4.

FIG. 6B is a diagram schematically illustrating a laser beam emission state in the DOE 114. As shown in FIG. 6B, the laser light is separated into diffracted light (diffracted light having a diffraction order other than 0) diffracted by the diffraction pattern of the DOE 114 and zero-order light that is not diffracted by the diffraction pattern. . In this embodiment, since the optical axis of the laser light source 111 is bent by the reflecting mirror 113 so as to be parallel to the Z axis, the 0th-order light transmitted through the DOE 114 travels in a direction parallel to the Z axis.

  FIG. 6C is a diagram schematically showing the arrangement of the light emitting units 111 a and 111 b in the laser light source 111. As described above, the laser light source 111 is composed of a frame type semiconductor laser.

  The laser light source 111 includes two light emitting units 111a and 111b that emit laser beams having different wavelength bands in one package. The light emitting units 111a and 111b are integrally formed on the substrate 111c so that the interval is Δd. The substrate 111c is installed on the frame 111d. The light emitting portions 111a and 111b are formed so as to be arranged in a straight line.

  In the present embodiment, the laser light source 111 is arranged such that the arrangement direction of the light emitting units 111a and 111b is parallel or substantially parallel to the Z-axis direction. Here, “substantially parallel” includes a state where the alignment direction of the light emitting units 111a and 111b is inclined about 10 degrees around the X axis from a state parallel to the Z axis.

  When the light emitting units 111a and 111b are arranged in this manner, the optical axes of the light emitting units 111a and 111b after being bent by the reflection mirror 113 are shifted from each other in a direction substantially parallel to the X axis. For this reason, the dot pattern generated by the DOE 114 is changed in the X-axis direction, that is, the alignment direction of the projection optical system 11 and the light receiving optical system 12 by switching the light emitting unit used for measurement between the light emitting units 111a and 111b. It will shift in a substantially parallel direction.

  FIGS. 7A and 7B are diagrams schematically showing a shift state of a dot pattern generated when the light emitting unit used for measurement is switched between the light emitting units 111a and 111b.

  FIG. 7A is a diagram showing the irradiation state of the dot pattern on the target area when the light emitting unit 111a is turned on. In FIG. 7A, the center of the dot pattern is irradiated with 0th-order diffracted light D0a that is transmitted through the DOE 114 without being diffracted by the DOE 114. L1a is a straight line indicating the center position of the dot pattern in the X-axis direction, and L2 is a straight line indicating the center position of the dot pattern in the Y-axis direction.

  FIG. 7B is a diagram showing the irradiation state of the dot pattern on the target area when the light emitting unit 111b is turned on. In FIG. 7B, the zero-order diffracted light D0b transmitted through the DOE 114 without being diffracted by the DOE 114 is irradiated to the center of the dot pattern. L1b is a straight line indicating the center position of the dot pattern in the X-axis direction, and L2 is a straight line indicating the center position of the dot pattern in the Y-axis direction, as in FIG. FIG. 7B shows a straight line L1a in FIG. 7A for convenience.

  As shown in FIG. 7B, when the light emitting section to be lit is switched from the light emitting section 111a to the light emitting section 111b, the dot pattern irradiated to the target area is shifted in the negative direction of the X axis by the distance ΔL. On the other hand, in the three-dimensional distance information acquisition mode described with reference to FIGS. 4A to 4C, a reference image for setting the segment region Sn is held in advance in the memory 25, and when actually measured, The above three-dimensional distance information acquisition process is performed for each segment area using the reference image held in 25.

In this case, for example, when the reference image is acquired and held in the memory 25 with the light emitting unit 111a out of the light emitting unit 111a and the light emitting unit 111b, as shown in FIGS. 7A and 7B, When the light emitting unit to be lit is switched to the light emitting unit 111b, the dot pattern is displaced by a distance ΔL in the negative direction of the X axis. The reference image is shifted by a distance ΔL in the negative X-axis direction. Therefore, when the three-dimensional distance information acquisition process is performed by turning on the light emitting unit 111b, the segment is used when the reference image (reference image acquired by turning on the light emitting unit 111a) is used. The displacement position in the X-axis direction on the actually measured image of the region Sn has an error by a distance ΔL, and the three-dimensional distance information also includes an error due to this error.

  Accordingly, when the reference image is acquired and held in the memory 25 in a state where the light emitting unit 111a is lit in this way, when the three-dimensional distance information is acquired by turning on the light emitting unit 111b, the dot pattern shifts. It is desirable to perform correction processing of three-dimensional distance information based on the amount (distance ΔL). For example, this correction processing is performed by moving the displacement position of the segment area detected by the above-described search by a dot pattern shift amount (distance ΔL) in the direction opposite to the dot pattern shift direction. If the error of the three-dimensional distance information based on the dot pattern deviation amount (distance ΔL) is slight, this correction process may be omitted.

  Further, instead of the method of performing such correction processing, a method of holding two reference images in the memory 25 when the light emitting units 111a and 111b are turned on can be used. In this case, when the light emitting unit 111a is turned on, the three-dimensional distance information acquisition process is performed using the reference image acquired by turning on the light emitting unit 111a, and when the light emitting unit 111b is turned on, Three-dimensional distance information acquisition processing is performed using a reference image acquired by turning on the light emitting unit 111b. However, in this case, since it is necessary to hold two reference images in the memory 25, it is necessary to hold the reference image as compared with the case where one reference image is held in the memory 25 as described above. There is a problem that the memory capacity increases. Therefore, in view of this problem, as described above, it is desirable to hold the reference image acquired when any one of the light emitting units 111a and 111b is lit in the memory 25.

  As shown in FIGS. 7A and 7B, when the light emitting unit to be lit is switched between the light emitting unit 111a and the light emitting unit 111b, the dot pattern is changed in the X-axis direction (projection optical system 11 and light receiving optical system). The configuration in which the laser light source 111 is arranged so as to shift in the direction in which the system 12 is arranged is an example of the configuration according to claim 3.

  FIG. 8 is a graph illustrating an example of wavelength variation characteristics of laser light emitted from the light emitting units 111a and 111b. In FIG. 8, the horizontal axis represents the temperature near the laser light source 111, and the vertical axis represents the wavelength (oscillation wavelength) of the laser light emitted from the light emitting units 111a and 111b. The temperature on the horizontal axis is detected by a temperature sensor 130 shown in FIG. Further, 830 nm and 820 nm shown at the right end of FIG. 8 are oscillation wavelengths of the light emitting units 111 a and 111 b when the temperature is 25 ° C., respectively.

  As shown in FIG. 8, the oscillation wavelengths of the light emitting units 111a and 111b become longer as the temperature rises. In each graph, the oscillation wavelength changes in a step shape due to mode hopping that occurs in the light emitting units 111a and 111b. Here, assuming that the use environment temperature is 0 ° C. to 60 ° C., the oscillation wavelength of the light emitting unit 111a changes in the range of 812.8 nm to 830.8 nm in the change range of the use environment temperature. The wavelength variation width Δλ1 of the laser light is 18 nm. Therefore, if only the light emitting unit 111a is arranged in the laser light source 111, it is necessary to set the transmission wavelength band of the filter 121 so as to transmit light having a wavelength included in the wavelength variation width Δλ1. is there.

On the other hand, in the present embodiment, in addition to the light emitting unit 111a, the light emitting unit 111b includes the laser light source 1.
11, the transmission wavelength band of the filter 121 can be narrowed compared to the case where only the light emitting unit 111 a is provided. That is, in the graph of FIG. 8, the laser is used so that the measurement is performed using the light emitting unit 111b in the temperature range of 0 to 30 ° C., and the measurement is performed using the light emitting unit 111a in the range of temperature of 30 to 60 ° C. The light source 111 is controlled. In this way, the fluctuation range of the wavelength of the laser light irradiated to the target region is from the oscillation wavelength (822.8 nm) of the light emitting unit 111a when the temperature is 30 ° C. to the oscillation wavelength of the light emitting unit 111b when the temperature is 30 ° C. The wavelength variation width Δλ2 of the laser light at this time is 8 nm.

  As described above, in the present embodiment, in the temperature range of the use environment temperature, the two light emitting units such that a part of the oscillation wavelength of the light emitting unit 111a and a part of the oscillation wavelength of the light emitting unit 111b overlap each other. The oscillation wavelengths 111a and 111b are set. For this reason, by switching the light emission part used for a measurement as mentioned above, the transmission wavelength band of the filter 121 can be narrowed to about 8 nm, and the quantity of the disturbance light which permeate | transmits the filter 121 can be suppressed. Therefore, according to this Embodiment, the precision of three-dimensional distance information can be improved.

  In this way, in the temperature range (0 to 60 ° C.) of the use environment temperature, these two light emission components are such that a part of the oscillation wavelength of the light emitting unit 111a and a part of the oscillation wavelength of the light emitting unit 111b overlap each other. The configuration in which the oscillation wavelengths of the units 111a and 111b are set is an example of the configuration according to claim 6.

  FIG. 9A is a flowchart showing switching processing of the light emitting units 111a and 111b. This flowchart is for the case where the oscillation wavelengths of the light emitting units 111a and 111b are set as shown in the graph of FIG. Here, in the memory 25 of FIG. 3, a threshold temperature Tsh having a temperature value of 30 ° C. is held as the switching condition 25a. 9A is performed by the function of the laser control unit 21a of the CPU 21 shown in FIG.

  The configuration in which the threshold temperature Ts is held in the memory 25 as the switching condition 25a is an example of the configuration according to claim 2.

  Referring to FIG. 9A, when the distance acquisition operation is started (S101: YES), the CPU 21 acquires the temperature T of the laser light source 111 by the temperature sensor 130 at a predetermined temperature acquisition timing (S102). ). Next, the CPU 21 determines whether or not the acquired temperature T is equal to or higher than the threshold temperature Tsh held as the switching condition 25a in the memory 25 (S103). When the acquired temperature T is equal to or higher than the threshold temperature Tsh, the CPU 21 turns on the light emitting unit 111a and turns off the light emitting unit 111b (S104). On the other hand, when the acquired temperature T is lower than the threshold temperature Tsh, the CPU 21 turns off the light emitting unit 111a and turns on the light emitting unit 111b (S104). As a result, the wavelength of the laser light emitted from the laser light source 111 is included in the range of the wavelength fluctuation range Δλ2 shown in FIG.

  Thus, when the light emitting unit used for the measurement is set, the CPU 21 determines whether or not the distance acquisition operation is finished (106). If the distance acquisition operation has not ended, the CPU 21 advances the process to S102 and executes the processes subsequent to S102 again. That is, the CPU 21 acquires the temperature T of the laser light source 111 by the temperature sensor 130 at a predetermined temperature acquisition timing (S102), and depending on whether the acquired temperature T is equal to or higher than the threshold temperature Tsh (S103). The light emitting unit used for measurement is switched between the light emitting unit 111a and the light emitting unit 111b (S104, S105). Hereinafter, similarly, the switching control of the light emitting units is performed until the distance acquisition operation is completed.

As described above, according to the present embodiment, the laser light source 111 is provided with the two light emitting units 111a and 111b, and based on the threshold temperature Tsh held in the memory 25 as the switching condition 25a and the temperature acquired by the temperature sensor 130. Thus, the light emitting unit used for measurement is switched between the light emitting unit 111a and the light emitting unit 111b. Therefore, as described with reference to FIG. 8, the transmission wavelength band of the filter 121 can be narrowed, and the amount of disturbance light transmitted through the filter 121 can be suppressed. Therefore, according to this Embodiment, the precision of the three-dimensional distance information acquired by the distance calculating part 21b can be improved.

  Further, according to the present embodiment, the laser light source 111, the collimator lens 112, the reflection mirror 113, and the DOE 114 are arranged so that the laser light source 111, the collimator lens 112, and the reflection mirror 113 are linearly arranged and the DOE 114 faces the target area. Be placed. Thereby, the height of the projection optical system 11 in the Z-axis direction can be lowered, and the information acquisition apparatus 1 can be downsized.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and the embodiments of the present invention can be variously modified in addition to the above. .

  For example, in the above embodiment, as shown in FIG. 6A, the laser light source 111 made of a frame type semiconductor laser is arranged so that the thickness direction is parallel or substantially parallel to the Y axis. As shown to (a), the laser light source 111 may be arrange | positioned so that the thickness direction may be parallel or substantially parallel to a Z-axis. If it carries out like this, compared with the said embodiment, the height of the projection optical system 11 in a Z-axis direction can be made still lower, and the further size reduction of the information acquisition apparatus 1 can be achieved.

  When the laser light source 111 is arranged in this manner, as shown in FIGS. 10B and 10C, when the light emitting unit to be lit is switched between the light emitting units 111a and 111b, the DP light (dot The direction in which the pattern) is shifted is a direction parallel to the Y axis. FIGS. 10B and 10C are diagrams schematically illustrating the irradiation state of the dot pattern on the target area when the light emitting units 111a and 111b are turned on, respectively. L2a is a straight line indicating the center position of the dot pattern in the Y-axis direction when the light emitting unit 111a is turned on, and L2b is the center position of the dot pattern in the Y-axis direction when the light emitting unit 111b is turned on. It is a straight line showing. When the light emitting unit to be lit is switched from the light emitting unit 111a to the light emitting unit 111b, the dot pattern irradiated to the target area shifts in the Y-axis negative direction by the distance ΔL ′.

  In this case, for example, when the reference image acquired when the light emitting unit 111a is turned on is held in the memory 25 and this reference image is also used when the light emitting unit 111b is turned on, as shown in FIG. The acquisition operation of the three-dimensional distance information described with reference to (b) and (c) may not be performed properly.

  FIGS. 11A and 11B are diagrams for explaining this problem. FIG. 11A schematically shows a search operation for the segment area Si when the light emitting unit 111a is turned on, and FIG. 11B shows a search for the segment area Si when the light emitting unit 111b is turned on. It is a figure which shows operation | movement typically.

  First, referring to FIG. 11A, as described above, when the reference image held in the memory 25 is acquired with the light emitting unit 111a turned on, the reference image is turned on during distance measurement. When the light emitting unit 111a is the light emitting unit 111a, the measured image acquired at the time of distance measurement and the reference image held in the memory 25 are not shifted from each other in the Y-axis direction. Therefore, as shown in FIG. 11A, the segment area Si is correctly matched with the comparison area Cj, and the search operation for the segment area Si is performed appropriately.

  On the other hand, when the light emitting unit to be lit is switched to the light emitting unit 111b, the reference image to be originally acquired is Y with respect to the reference image held in the memory 25 as shown in FIG. Since it is shifted by the distance ΔL ′ in the negative axis direction, the actually measured image acquired at the time of measuring the distance is also shifted by the distance ΔL ′ in the negative Y axis direction with respect to the reference image held in the memory 25. For this reason, as shown in FIG. 11B, the comparison region matching the segment region Si is also shifted by the distance ΔL ′ in the negative Y-axis direction with respect to the search range in the X-axis direction of the segment region Si. . In this case, even if the segment area Si is searched, the segment area Si does not match the comparison area Cj as shown in FIG. 11B, and the search operation for the segment area Si is likely to cause an error. .

  Therefore, as shown in FIG. 10A, when the laser light source 111 is arranged so that the thickness direction is parallel or substantially parallel to the Z axis, the projection optical system 11 in the Z axis direction is compared with the above embodiment. Although the height can be further reduced, on the other hand, the search for the segment area becomes an error, and it may happen that the three-dimensional distance information cannot be acquired properly. On the other hand, when the laser light source 111 is arranged so that the thickness direction is parallel or substantially parallel to the Y axis as in the above embodiment, as shown in FIGS. Although the reference image and the actual measurement image may be shifted from each other in the X-axis direction, the reference image and the actual measurement image are not shifted from each other in the Y-axis direction. It can never happen that is not acquired. Therefore, in order to avoid an error in obtaining the three-dimensional distance information, the laser light source 111 is arranged so that the thickness direction is parallel or substantially parallel to the Y axis as in the above embodiment. desirable.

  As the distance ΔL ′ shown in FIG. 10C decreases, the amount of shift in the Y-axis direction between the segment region Si and the comparison region Cj in FIG. In this case, the possibility that the segment region Si correctly matches the comparison region Cj is increased. Here, the distance ΔL ′ shown in FIG. 10C corresponds to the distance Δd between the light emitting unit 111a and the light emitting unit 111b shown in FIG. 6C. Therefore, when the distance Δd between the light emitting unit 111a and the light emitting unit 111b is small enough to correctly match the segment region Si with the comparison region Cj, the thickness direction is parallel to the Z axis as shown in FIG. Alternatively, it is desirable to arrange the laser light source 111 so as to be substantially parallel so as to reduce the height of the projection optical system 11 in the Z-axis direction.

  As shown in FIG. 10A, the laser light source 111 is arranged so that the thickness direction of the laser light source 111 is substantially parallel to the Z axis, that is, the arrangement direction of the light emitting units 111a and 111b (laser light source). The configuration in which the laser light source 111 is disposed so that the width direction of the laser beam 111 is substantially perpendicular to the plane (XZ plane) including the optical axis of the collimator lens 112 before and after being bent by the reflection mirror 113 is described in claim 5. It is an example of the structure of description.

  In the modified example shown in FIG. 10A as well, the reference image is held in the memory 25 for each light emitting unit, and is used for searching the segment area according to the light emitting unit used for measurement, as in the above embodiment. The reference image may be switched. However, in this case, there arises a problem that the memory capacity for storing the reference image becomes large as described above.

  Moreover, in the said embodiment, the light emission part used for a measurement was switched between the light emission part 111a and the light emission part 111b by whether the temperature T detected by the temperature sensor 130 is more than threshold temperature Tsh. . However, the conditions for switching the light emitting units are not limited to this, and other conditions that can appropriately select a light emitting unit whose oscillation wavelength is included in the transmission wavelength band of the filter 121 may be used.

For example, in the flowchart shown in FIG. 12A, the light emitting units used for the measurement are the light emitting unit 111a and the light emitting unit 111b depending on whether or not the total received light amount R of the CMOS image sensor 124 is equal to or less than the threshold value Rsh. Can be switched between. That is, in the process of FIG. 12A, when the distance acquisition operation is started (S111: YES), the light emitting unit 111a is turned off and the light emitting unit 111b is turned on (S112). Then, at a predetermined timing, the total received light amount R of the CMOS image sensor 124 is acquired (S113), and it is determined whether or not the acquired total received light amount R is equal to or less than the threshold value Rsh (S114).

  If the acquired total received light amount R is less than or equal to the threshold value Rsh (S114: YES), the oscillation wavelength of the currently used light emitting unit (here, the light emitting unit 111a) changes the transmission wavelength band of the filter 121 due to the temperature change. The light emitting unit used for measurement is switched to the other light emitting unit (here, the light emitting unit 111b) (S115). If the acquired total received light amount R is not less than or equal to the threshold value Rsh (S114: NO), the oscillation wavelength of the currently used light emitting unit (here, the light emitting unit 111a) is still the transmission wavelength band of the filter 121. The light emitting unit currently used is used as it is for measurement. The above process is repeated until the distance acquisition operation is completed (S116: YES).

  In the flowchart of FIG. 12A, the threshold value Rsh is held in the memory 25 as the switching condition 25a. Here, the threshold value Rsh is set so that the oscillation wavelength of the selected light emitting unit is included in the transmission wavelength band of the filter 121.

  Further, in the flowchart shown in FIG. 12B, the light emitting units used for the measurement are the light emitting units 111a and 111b depending on whether or not the error rate E of the search process for the segment area is equal to or higher than the threshold Esh. Can be switched between. In the flowchart of FIG. 12B, S113 and S114 in the flowchart of FIG. 12A are replaced with S121 and S122.

  That is, in the flowchart of FIG. 12B, when the distance acquisition operation is started (S111: YES), the light emitting unit 111a is turned off and the light emitting unit 111b is turned on (S112). Then, at a predetermined timing, the error rate E of the search process for the segment area is acquired (S121), and it is determined whether or not the acquired error rate E is equal to or higher than the threshold value Esh (S121). If the acquired error rate E is equal to or greater than the threshold value Esh (S121: YES), the oscillation wavelength of the currently used light emitting unit (here, the light emitting unit 111a) changes the transmission wavelength band of the filter 121 due to temperature change. It is determined that the error rate has increased due to the disconnection, and the light emitting unit used for measurement is switched to the other light emitting unit (here, the light emitting unit 111b) (S115). If the acquired error rate E is not equal to or higher than the threshold value Esh (S114: NO), the oscillation wavelength of the currently used light emitting unit (here, the light emitting unit 111a) is still in the transmission wavelength band of the filter 121. It is determined that it is included, and the currently used light emitting unit is used for measurement as it is.

  In the flowchart of FIG. 12B, the threshold value Esh is held in the memory 25 as the switching condition 25a. Here, the threshold value Esh is set so that the oscillation wavelength of the selected light emitting unit is included in the transmission wavelength band of the filter 121 as in the case of FIG.

  In the above embodiment, the laser light source 111 is provided with the two light emitting units 111 a and 111 b, but three or more light emitting units may be provided in the laser light source 111. Also in this case, as in the above embodiment, the oscillation wavelength of each light emitting unit is set so that the transmission wavelength band of the filter 121 can be narrowed compared to the case where one light emitting unit is used. Similarly to the above embodiment, one light emitting unit is selected from among the plurality of light emitting units so that the oscillation wavelength of the selected light emitting unit is included in the transmission wavelength band of the filter 121 at the operating environment temperature at that time. , Selected as a light emitting unit used for measurement.

  FIGS. 13A and 13B are diagrams illustrating a configuration example when three light emitting units 111e to 111g are arranged in the laser light source 111. FIG. In this case, as shown in FIG. 13B, three light emitting portions 111e to 111g are formed on the substrate 111c so as to be arranged in a straight line. Moreover, these three light emission parts 111e-111g have the oscillation characteristic shown to Fig.13 (a). When the operating temperature range is 0 to 60 ° C., the light emitting portion 111e is used for measurement in the range of 0 to 23 ° C., and the light emitting portion 111f is used for measurement in the range of 23 ° C. to 40 ° C., and 40 ° C. to 60 ° C. In the range of ° C., the light emitting portion 111g is used for measurement.

  When the light emitting units 111e to 111f are controlled to be switched in this way, the variation range of the wavelength of the laser light irradiated to the target region is from the oscillation wavelength (about 830 nm) of the light emitting unit 111e when the temperature is 30 ° C. The oscillation wavelength (approximately 836 nm) of the light emitting unit 111e at 23 ° C. is in the range, and the wavelength variation width Δλ3 of the laser light at this time is approximately 6 nm. Therefore, the wavelength variation width Δλ3 of the laser light can be further narrowed and the transmission wavelength band of the filter 121 can be further narrowed compared to the above embodiment. Therefore, the amount of disturbance light transmitted through the filter 121 can be further suppressed, and the accuracy of the three-dimensional distance information acquired by the distance calculation unit 21b can be further increased.

  FIG. 14A is a flowchart showing the control processing by the laser control unit 21a in this case, and FIG. 14B is a diagram showing the switching condition 25a held in the memory 25.

  In this modified example, as shown in FIG. 14B, two threshold temperatures Tsh1 and Tsh2 are held as the switching condition 25a. When the light emitting units 111e to 111f have the oscillation characteristics shown in FIG. 13A, the threshold temperature Tsh1 is 23 ° C. and the threshold temperature Tsh2 is 40 ° C.

  In the flowchart of FIG. 14A, when the temperature T (S102) of the laser light source 111 acquired at a predetermined timing is lower than the threshold temperature Tsh1 (S131: NO, S132: NO), the CPU 21 turns on the light emitting unit e. Turn on (S135). When the temperature T is equal to or higher than the threshold temperature Tsh1 and lower than the threshold temperature Tsh2 (S131: NO, S132: YES), the CPU 21 turns on the light emitting unit 111f (S134). When the temperature T is equal to or higher than the threshold temperature Tsh2 (S131: YES), the CPU 21 turns on the light emitting unit 111g (S133).

  In FIGS. 14A and 14B, the light emitting units 111e to 111g are controlled to be switched according to the temperature acquired by the temperature sensor 130. However, similarly to FIGS. 12A and 12B, The light emitting units 111e to 111g may be switch-controlled based on the total received light amount of the CMOS image sensor 124 or the error rate when searching for the segment area. In this case, the light emitting unit 111f whose oscillation wavelength is between the other two oscillation wavelengths is first turned on, and then the total received light amount of the CMOS image sensor 124 or the error rate when searching for the segment area no longer satisfies the threshold value. The light emitting unit used for measurement is switched to the light emitting unit satisfying the threshold value among the light emitting units 111e and 111f.

  In this way, the configuration in which the three light emitting units 111e to 111g in which a part of the emission wavelength band overlap with each other is arranged in the laser light source 111 and the two threshold temperatures Tsh1 and Tsh2 are used as the switching condition 25a is described in claim 7. It is an example of the structure of description.

  In the above embodiment, the thickness direction of the laser light source 111 is substantially parallel to the Y axis. In the modification shown in FIG. 10A, the thickness direction of the laser light source 111 is substantially parallel to the Z axis. The arrangement of the laser light source 111 is not limited to these arrangements. For example, the laser light source 111 may be arranged such that the thickness direction of the laser light source 111 is inclined by about 45 ° with respect to the Y axis and the Z axis.

  Moreover, in the said embodiment, as shown in FIG. 8, the temperature range of use environment temperature was divided | segmented into the first half and the second half, and the light emission part used was switched by the first half and the second half of the said temperature range. However, the temperature for switching the light emitting unit to be used is not necessarily an intermediate temperature in the temperature range of the operating environment temperature, and is appropriately adjusted to a predetermined temperature according to the oscillation wavelength of each light emitting unit. obtain.

  In the above embodiment, a frame type semiconductor laser is used as the laser light source 111. However, a CAN type semiconductor laser may be used.

  In the above embodiment, the CMOS image sensor 124 is used as the light receiving element. However, a CCD image sensor can be used instead.

  In the above embodiment, the optical axis of the laser light source 111 is configured to be bent by the reflection mirror 113. However, the reflection mirror 113 is omitted, and the laser light source 111, the collimator lens 112, and the DOE 114 are arranged in a straight line. You may comprise the projection optical system 11 so that it may arrange | position. In this case, the reflection mirror 113 can be omitted, but the size of the projection optical system 11 increases in the direction of DP light emission. Furthermore, the configuration of the light receiving optical system 12 can be changed as appropriate.

  Moreover, in the said embodiment, although the information acquisition apparatus 1 and the information processing apparatus 2 were separate bodies, these may be integrated, Furthermore, these may be incorporated in the television 3 or another apparatus. .

  In addition, the embodiment of the present invention can be variously modified as appropriate within the scope of the technical idea shown in the claims.

DESCRIPTION OF SYMBOLS 1 ... Information acquisition apparatus 2 ... Information processing apparatus 11 ... Projection optical system 12 ... Light reception optical system 21a ... Laser control part 21b ... Distance calculation part (distance acquisition part)
25 ... Memory 25a ... Switching condition 111 ... Laser light source (light source)
111a, 111b ... Light emitting part 111e, 111f, 111c ... Light emitting part 112 ... Collimator lens (lens)
113 ... Reflection mirror 114 ... DOE (diffractive optical element)
121… Filter 130… Temperature sensor

Claims (8)

A laser light source including a plurality of light emitting units that emit laser beams having different wavelengths;
A projection optical system for projecting the laser light emitted from the laser light source onto a target area with a predetermined dot pattern;
The filter is disposed in one direction away from the projection optical system, and includes a filter for transmitting the reflected light reflected from the target area, receiving the reflected light transmitted through the filter, and A light receiving optical system for imaging by an image sensor;
A distance acquisition unit that acquires distance information related to a distance to an object included in the target area based on an actual measurement image including the dot pattern imaged by the image sensor at the time of actual measurement;
A laser control unit for controlling the laser light source,
The laser control unit holds a predetermined switching condition for switching a light emitting unit used for measurement from one light emitting unit to another light emitting unit among the plurality of light emitting units due to a change in an emission wavelength band based on a temperature change, An information acquisition apparatus that determines a light emitting unit to be used for measurement among the plurality of light emitting units based on the switching condition. The information acquisition device according to claim 1,
A temperature sensor for detecting the temperature of the laser light source;
The laser control unit holds whether the temperature detected by the temperature sensor is equal to or higher than a predetermined threshold as the switching condition.
An information acquisition apparatus characterized by that. In the information acquisition device according to claim 1 or 2,
The plurality of light emitting units are arranged such that a direction in which a dot pattern shifts in a target region when a light emitting unit used for measurement is switched from one light emitting unit to another light emitting unit is an alignment of the projection optical system and the light receiving optical system. Arranged so as to be substantially parallel to the direction,
An information acquisition apparatus characterized by that. In the information acquisition device according to any one of claims 1 to 3,
The projection optical system includes a collimator lens on which the laser light emitted from the laser light source is incident, a mirror that reflects light transmitted through the collimator lens, and light reflected by the mirror as light of the dot pattern. A diffractive optical element for conversion, the laser light source, the collimator lens, and the mirror are arranged in a straight line, and the diffractive optical element faces the target area, the laser light source, the collimator lens, the mirror, and the mirror A diffractive optical element is disposed;
An information acquisition apparatus characterized by that. The information acquisition device according to claim 4,
The laser light source is a frame type semiconductor laser,
In the semiconductor laser, the plurality of light emitting units are arranged in a line in a direction perpendicular to a laser beam emission direction,
The semiconductor laser is arranged so that the arrangement direction of the plurality of light emitting units is substantially perpendicular to a plane including the optical axis of the collimator lens before and after being bent by the mirror.
An information acquisition apparatus characterized by that. In the information acquisition device according to any one of claims 1 to 5,
The laser light source emits a laser beam having a first wavelength band in a predetermined temperature band.
And a second light emitting unit that emits laser light in a second wavelength band that partially overlaps the first wavelength band in the temperature band,
The switching condition is defined such that a light emitting unit that emits laser light having a wavelength included in the transmission wavelength band of the filter is selected from the first and second light emitting units.
An information acquisition apparatus characterized by that. In the information acquisition device according to any one of claims 1 to 5,
The laser light source includes three light emitting units in which a part of the emission wavelength band overlaps with each other in a predetermined temperature band,
The switching condition is defined such that a light emitting unit that emits laser light having a wavelength included in the transmission wavelength band of the filter is selected from the three light emitting units.
An information acquisition apparatus characterized by that.   The object detection apparatus which has an information acquisition apparatus as described in any one of Claims 1 thru | or 7.

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