Distance measuring device

Abstract

To provide a ranging device for receiving light using a single photon avalanche diode capable of increasing the resolution of light intensity while suppressing the decrease in optical SN ratio.SOLUTION: A ranging device 10 includes: a light emitting unit 20 that emits irradiation light Lo; a light-receiving part 60 that has a light-receiving surface 61 in which each pixel 65 consists of multiple single photon avalanche diodes 68, which is a light-receiving surface that receives incident light Li that includes reflected light from the irradiation light; an aperture section 50 that has an opening 55 through which the incident light enters, and limits the amount of incident light passing through; and an optical system 40 that is an optical system with different refractive powers in the longitudinal direction of the opening and the lateral direction of the opening, in which the incident light is focused on the light receiving surface in the longitudinal direction and the incident light is focused on the opening in the lateral direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a distance measuring device. [Background technology]

[0002] Patent Document 1 discloses a distance measuring device that measures the distance to an object by measuring the time it takes for laser light to be emitted, reflected by the object, and incident on a detector equipped with a single photon avalanche diode (SPAD). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 10,663,586 Summary of the Invention [Problem to be solved by the invention]

[0004] Because the output signal of a SPAD is binary, in order to measure light intensity at multiple stages using a SPAD, it is necessary to configure one pixel on the light-receiving surface with multiple SPADs. However, if the number of SPADs constituting one pixel is increased without changing the size of each SPAD, the amount of ambient light incident on each pixel increases as the area of ​​each pixel increases, resulting in a decrease in the ratio of the amount of signal light (laser light) to the amount of ambient light incident on each pixel (hereinafter referred to as the optical SNR), which may make it impossible to measure the distance to an object. Therefore, there is a need for technology that can improve the resolution of light intensity while suppressing the decrease in the optical SNR. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] According to one aspect of the present disclosure, there is provided a distance measuring device (10). The distance measuring device includes: a light emitting unit (20) that emits illumination light (Lo); a light receiving unit (60) having a light receiving surface (61) that receives incident light (Li) including reflected light of the illumination light, with each pixel (65) being composed of a plurality of single-photon avalanche diodes (68); an aperture unit (50) having an aperture (55) through which the incident light entering the light receiving unit passes and that limits the amount of the incident light that passes; and an optical system (40) that has different refractive powers in the longitudinal direction and the lateral direction of the aperture, and that focuses the incident light on the light receiving surface in the longitudinal direction and focuses the incident light on the aperture in the lateral direction.

[0007] According to the distance measuring device of this embodiment, it is possible to improve the resolution of the light intensity while suppressing the decrease in the optical SNR. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram showing a schematic configuration of a distance measuring device according to a first embodiment. [Figure 2] FIG. 2 is a perspective view showing a light-collecting optical system, a diaphragm unit, and a light-receiving unit according to the first embodiment. [Figure 3] FIG. 1 is a first cross-sectional view showing the configuration of a light-collecting optical system according to a first embodiment. [Figure 4] FIG. 2 is a second cross-sectional view showing the configuration of the light-collecting optical system of the first embodiment. [Figure 5] FIG. 2 is an explanatory diagram showing the configuration of a light receiving surface according to the first embodiment. [Figure 6] FIG. 10 is an explanatory diagram showing how the number of columns of light receiving elements constituting one pixel is increased. [Figure 7] FIG. 10 is a first cross-sectional view showing the configuration of a light-collecting optical system according to a second embodiment. [Figure 8] FIG. 10 is a second cross-sectional view showing the configuration of the light-collecting optical system according to the second embodiment. [Figure 9] FIG. 10 is a first cross-sectional view showing the configuration of a light-collecting optical system according to a third embodiment. [Figure 10] FIG. 10 is a second cross-sectional view showing the configuration of the light-collecting optical system according to the third embodiment. [Figure 11]FIG. 10 is a first cross-sectional view showing the configuration of a light-collecting optical system according to a fourth embodiment. [Figure 12] FIG. 10 is a second cross-sectional view showing the configuration of the light-collecting optical system according to the fourth embodiment. [Figure 13] FIG. 10 is an explanatory diagram showing a schematic configuration of a distance measuring device according to a fifth embodiment. [Figure 14] FIG. 10 is an explanatory diagram showing the configuration of a throttle portion according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] A. First embodiment: 1, in this embodiment, the distance measuring device 10 includes a light emitting unit 20, a scanning unit 30, a focusing optical system 40, an aperture unit 50, a light receiving unit 60, a control unit 70, and a housing 80. The light emitting unit 20, the scanning unit 30, the focusing optical system 40, the aperture unit 50, the light receiving unit 60, and the control unit 70 are housed in the housing 80. Note that the control unit 70 may be housed in a housing separate from the housing 80.

[0010] The light-emitting unit 20 emits illumination light Lo. In this embodiment, the light-emitting unit 20 includes an edge-emitting laser diode. The light-emitting unit 20 emits linear laser light along the vertical direction of the distance measuring device 10 as the illumination light Lo from an end face of the laser diode arranged parallel to the vertical direction of the distance measuring device 10. The scanning unit 30 includes a mirror 31 that reflects the illumination light Lo, a motor 32 that rotates the mirror 31 around a rotation axis RX that is parallel to the vertical direction of the distance measuring device 10, and a rotation angle sensor 33 that detects the rotation angle of the mirror 31. The scanning unit 30 rotates the mirror 31 using the motor 32, thereby scanning the illumination light Lo emitted from the light-emitting unit 20 along the horizontal direction of the distance measuring device 10. If an object is present within the scanning range SR, which is the range scanned by the illumination light Lo, the illumination light Lo is reflected by the surface of the object, and incident light Li, including reflected light of the illumination light Lo, returns to the mirror 31. The incident light Li is reflected by the mirror 31 and enters the focusing optical system 40.

[0011] The focusing optical system 40 includes at least one lens and focuses the incident light Li. The diaphragm unit 50 is disposed behind the focusing optical system 40 in the direction of travel of the incident light Li. The diaphragm unit 50 is made of a light-blocking material and has an opening 55 that passes through the incident light Li. The light-receiving unit 60 is disposed behind the diaphragm unit 50 in the direction of travel of the incident light Li. The light-receiving unit 60 includes a light-receiving surface 61 that receives the incident light Li. The incident light Li that passes through the focusing optical system 40 and the opening 55 of the diaphragm unit 50 is incident on the light-receiving surface 61. The light-receiving surface 61 is configured with a plurality of light-receiving elements 68 that detect the incident light Li. In this embodiment, the light-receiving elements 68 are single-photon avalanche diodes.

[0012] The control unit 70 is configured as a computer including a CPU, memory, an input / output interface for inputting and outputting signals to and from the outside, and an internal bus. The control unit 70 controls the light-emitting unit 20, the scanning unit 30, and the light-receiving unit 60 to measure the distance between the object present within the scanning range SR and the distance measuring device 10. Specifically, the control unit 70 causes the light-emitting unit 20 to emit pulsed illumination light Lo, measures the time from when the illumination light Lo is emitted until the incident light Li is detected by the light-receiving unit 60, and calculates the distance between the distance measuring device 10 and a reflection point on the object using the measured time. In this embodiment, the control unit 70 causes the light-emitting unit 20 to emit pulsed illumination light Lo while rotating the mirror 31 using the motor 32. The control unit 70 detects the rotation angle of the mirror 31 when the incident light Li is detected using the rotation angle sensor 33, and uses the rotation angle to determine the azimuth angle of the reflection point on the object relative to the distance measuring device 10.

[0013] 2, in this embodiment, the diaphragm unit 50 is configured in a flat plate shape. An opening 55 of the diaphragm unit 50 is formed in a slit shape, that is, in a long and narrow rectangular shape. The longitudinal direction of the opening 55 is parallel to the vertical direction Dv of the distance measuring device 10, and the lateral direction of the opening 55 is parallel to the horizontal direction Dh of the distance measuring device 10. The diaphragm unit 50 is disposed opposite the light receiving surface 61 of the light receiving unit 60, and limits the amount of incident light Li that passes through.

[0014] The focusing optical system 40 is disposed on the opposite side of the diaphragm unit 50 from the light receiving surface 61. The focusing optical system 40 has positive refractive power in the horizontal direction Dh and the vertical direction Dv. The refractive power of the focusing optical system 40 differs between the horizontal direction Dh and the vertical direction Dv. Since the refractive power is equal to the reciprocal of the focal length, the focal length of the focusing optical system 40 differs between the horizontal direction Dh and the vertical direction Dv. In this embodiment, the focal length Fh of the focusing optical system 40 in the horizontal direction Dh is shorter than the focal length Fv of the focusing optical system 40 in the vertical direction Dv. The focusing optical system 40, the diaphragm unit 50, and the light-receiving unit 60 are arranged so that the center of the opening 55 is located on an extension of the optical axis OA of the focusing optical system 40, the distance between the principal point OC of the focusing optical system 40 and the center of the opening 55 is the same as the focal length Fh of the focusing optical system 40 in the horizontal direction Dh, and the distance between the principal point OC of the focusing optical system 40 and the light-receiving surface 61 is the same as the focal length Fv of the focusing optical system 40 in the vertical direction Dv, and the focusing optical system 40 focuses the incident light Li at the center of the opening 55 in the horizontal direction Dh, and focuses the incident light Li on the light-receiving surface 61 in the vertical direction Dv. Therefore, the incident light Li is incident on the light-receiving surface 61 defocused in the horizontal direction Dh, and just-focused in the vertical direction Dv.

[0015] In FIGS. 1 and 2 , the focusing optical system 40 is simplified and illustrated as a single lens. However, as shown in FIGS. 3 and 4 , in this embodiment, the focusing optical system 40 is composed of a first lens 41 and a second lens 42 disposed between the first lens 41 and the diaphragm unit 50. In this embodiment, the first lens 41 is a cylindrical lens, more specifically, a concave cylindrical lens having a central axis parallel to the horizontal direction Dh, and is disposed so that its flat surface faces the mirror 31 and its cylindrical surface having a curvature in the vertical direction Dv faces the second lens 42. The second lens 42 is a spherical lens, more specifically, a plano-convex lens, and is disposed so that its spherical surface having a curvature in the horizontal direction Dh and the vertical direction Dv faces the first lens 41 and its flat surface faces the diaphragm unit 50. The cylindrical surface here refers to a curved surface obtained by cutting out a portion of a cylindrical surface, and the spherical surface here refers to a curved surface obtained by cutting out a portion of a spherical surface. In this embodiment, the light-collecting optical system 40 is made up of two lenses 41 and 42, and therefore the focal lengths Fh and Fv of the light-collecting optical system 40 described above are the combined focal lengths of the two lenses 41 and 42.

[0016] As shown in FIG. 5, the light receiving surface 61 has a plurality of pixels 65 arranged in a grid pattern along the horizontal direction Dh and the vertical direction Dv. Each pixel 65 is composed of a plurality of light receiving elements 68 arranged in a grid pattern along the horizontal direction Dh and the vertical direction Dv. In the following description, each pixel 65 will be referred to as one pixel 65. In this embodiment, the length of one pixel 65 in the horizontal direction Dh is longer than the length of one pixel 65 in the vertical direction Dv. The length of one pixel 65 in the horizontal direction Dh is longer than the length of the opening 55 in the horizontal direction Dh. In FIG. 5, the region where the incident light Li is incident on the light receiving surface 61 is indicated by a dashed line. In this embodiment, the incident light Li is incident on one column of pixels 65. Note that in this embodiment, the region where the incident light Li is incident does not move even if the mirror 31 is rotated.

[0017] The position resolution of the distance measuring device 10 in the vertical direction Dv is determined by the center-to-center distance between adjacent pixels 65 in the vertical direction Dv. The azimuthal resolution of the distance measuring device 10 is determined by the amount of change in the rotation angle of the mirror 31 during the time interval at which the illumination light Lo is emitted. Because the light receiving elements 68 are single-photon avalanche diodes, the light intensity resolution of the distance measuring device 10 is determined by the number of light receiving elements 68 that make up one pixel 65.

[0018] The distance measuring device 10 is mounted on a vehicle, for example, and used to measure the distance between the vehicle and an object such as a person or an obstacle. Because the reflectance of the irradiated light Lo differs between the asphalt surface and the white lines on a road, the light intensity of the reflected light differs when the irradiated light Lo is reflected by the asphalt surface and when the irradiated light Lo is reflected by the white line. Therefore, the position of the white line can be estimated using the light intensity at each reflection point measured by the distance measuring device 10. However, if the light intensity resolution is not high enough, it is not possible to distinguish between the white line and the asphalt surface, and therefore the position of the white line cannot be estimated.

[0019] As shown in FIG. 6, when the number of light-receiving elements 68 constituting one pixel 65 is increased from 3 × 3 (vertical × horizontal) = 9 to 3 × 8 (vertical × horizontal) = 24, the light intensity resolution can be improved from 9 levels to 24 levels. However, in a configuration in which the aperture section 50 is not provided, increasing the number of columns of light-receiving elements 68 constituting one pixel 65 in the horizontal direction Dh increases the area of ​​each pixel 65, which may increase the amount of ambient light incident on each pixel 65 and reduce the optical signal-to-noise ratio. For example, in an environment in which ambient light is uniformly incident on the light-receiving surface 61 from between the focusing optical system 40 and the light-receiving surface 61, the amount of ambient light incident on each pixel 65 increases by 8 / 3 times. However, even if the horizontal length Dh of the incident light Li on the light-receiving surface 61 is increased by increasing the defocus amount, the amount of incident light Li incident on each pixel 65 does not increase, and the optical signal-to-noise ratio decreases by 3 / 8 times.

[0020] Furthermore, in a configuration in which the refractive power of the focusing optical system 40 is the same in the horizontal direction Dh and the vertical direction Dv, if the amount of defocus in the horizontal direction Dh is increased in accordance with an increase in the number of columns in the horizontal direction Dh of the light receiving elements 68 that make up one pixel 65, the amount of defocus in the vertical direction Dv also increases, and therefore the density of the incident light Li in the vertical direction Dv decreases, the amount of incident light Li that enters one pixel 65 decreases, and the optical SNR decreases. If the number of rows in the vertical direction Dv of the light receiving elements 68 that make up one pixel 65 is increased so as not to decrease the optical SNR, the positional resolution in the vertical direction Dv decreases.

[0021] In contrast, according to the distance measuring device 10 of the present embodiment described above, the diaphragm section 50 having the slit-shaped opening 55 whose longitudinal direction is parallel to the vertical direction Dv and whose lateral direction is parallel to the horizontal direction Dh is disposed between the light collecting optical system 40 and the light receiving surface 61, so that even if the number of columns of the light receiving elements 68 constituting one pixel 65 in the horizontal direction Dh is increased, the amount of disturbance light incident on one pixel 65 does not increase. In addition, since the distance measuring device 10 includes the light collecting optical system 40 having different refractive powers in the horizontal direction Dh and the vertical direction Dv, an increase in the amount of defocus in the vertical direction Dv that occurs when the amount of defocus in the horizontal direction Dh is increased in accordance with an increase in the number of columns of the light receiving elements 68 constituting one pixel 65 in the horizontal direction Dh can be suppressed, thereby suppressing a decrease in the optical SNR. Therefore, by increasing the number of columns in the horizontal direction Dh of the photodetectors 68 that constitute one pixel 65 and increasing the amount of defocus in the horizontal direction Dh without changing the amount of defocus in the vertical direction Dv, it is possible to increase the light intensity resolution while suppressing a decrease in the optical signal-to-noise ratio, and to suppress a decrease in the positional resolution in the vertical direction Dv.

[0022] Furthermore, in this embodiment, the first lens 41 of the focusing optical system 40 is a concave cylindrical lens and the second lens is a plano-convex lens, so that by adjusting the position and orientation of the second lens 42 and then adjusting the position and orientation of the first lens 41, it is possible to easily align the focusing optical system 40, the diaphragm unit 50, and the light-receiving surface 61. Note that it is also possible to align the focusing optical system 40, the diaphragm unit 50, and the light-receiving surface 61 by adjusting the position and orientation of the diaphragm unit 50 and then the position and orientation of the light-receiving surface 61 without moving the first lens 41 and the second lens 42.

[0023] Furthermore, in this embodiment, the length of the opening 55 of the aperture section 50 in the horizontal direction Dh is shorter than the length of one pixel 65 in the horizontal direction Dh, and therefore the aperture section 50 can effectively suppress an increase in the amount of ambient light incident on one pixel 65.

[0024] In addition, in this embodiment, the light-emitting unit 20 emits linear irradiation light Lo along the vertical direction Dv, and the light-receiving surface 61 has a plurality of pixels 65 arranged along the vertical direction Dv, so that positional resolution in the vertical direction Dv can be ensured.

[0025] Furthermore, this embodiment includes a scanning unit 30 that scans the illumination light Lo emitted from the light-emitting unit 20 along the horizontal direction Dh by rotating the mirror 31 and causes the incident light Li to enter the focusing optical system 40, and the azimuthal resolution is determined by the amount of change in the rotation angle of the mirror 31 during the time interval at which the illumination light Lo is emitted. Therefore, even if the number of columns of the light-receiving elements 68 that make up one pixel 65 in the horizontal direction Dh is increased to improve the light intensity resolution, the azimuthal resolution does not decrease.

[0026] B. Second embodiment: As shown in FIGS. 7 and 8 , the distance measuring device 10b of the second embodiment differs from the first embodiment in the configuration of the focusing optical system 40b. Specifically, in this embodiment, the first lens 41b of the focusing optical system 40b is a convex cylindrical lens having a central axis parallel to the vertical direction Dv, and is disposed so that its cylindrical surface having a curvature in the horizontal direction Dh faces the mirror 31 and its flat surface faces the second lens 42b. The second lens 42b of the focusing optical system 40b is a plano-convex lens, and is disposed so that its spherical surface having a curvature in both the horizontal direction Dh and the vertical direction Dv faces the first lens 41b and its flat surface faces the diaphragm unit 50. The other configurations are the same as those of the first embodiment. As with the first embodiment, the distance measuring device 10b of the second embodiment described above can increase the light intensity resolution while suppressing a decrease in the optical signal-to-noise ratio, and can suppress a decrease in the position resolution in the vertical direction Dv.

[0027] C. Third embodiment: As shown in FIGS. 9 and 10 , the distance measuring device 10c of the third embodiment differs from the first embodiment in the configuration of the focusing optical system 40c. Specifically, in this embodiment, the first lens 41c of the focusing optical system 40c is a plano-convex lens, and is disposed so that its spherical surface, which has curvatures in the horizontal direction Dh and the vertical direction Dv, faces the mirror 31 and its flat surface faces the second lens 42c. The second lens 42c of the focusing optical system 40c is a concave cylindrical lens with a central axis parallel to the horizontal direction Dh, and is disposed so that its flat surface faces the first lens 41c and its cylindrical surface, which has curvature in the vertical direction Dv, faces the diaphragm unit 50. The other configurations are the same as those of the first embodiment. As with the first embodiment, the distance measuring device 10c of the third embodiment described above can increase the light intensity resolution while suppressing a decrease in the optical signal-to-noise ratio, and can suppress a decrease in the position resolution in the vertical direction Dv.

[0028] D. Fourth embodiment: As shown in FIGS. 11 and 12 , the distance measuring device 10d of the fourth embodiment differs from the first embodiment in the configuration of the focusing optical system 40d. Specifically, in this embodiment, the first lens 41d of the focusing optical system 40d is a convex cylindrical lens having a central axis parallel to the horizontal direction Dh, and is disposed so that its cylindrical surface having a curvature in the vertical direction Dv faces the mirror 31 and its flat surface faces the second lens 42d. The second lens 42d of the focusing optical system 40d is a convex cylindrical lens having a central axis parallel to the vertical direction Dv, and is disposed so that its cylindrical surface having a curvature in the horizontal direction Dh faces the first lens 41d and its flat surface faces the diaphragm unit 50. The other configurations are the same as those of the first embodiment. As with the first embodiment, the distance measuring device 10d of the fourth embodiment described above can increase the light intensity resolution while suppressing a decrease in the optical signal-to-noise ratio, and can suppress a decrease in the position resolution in the vertical direction Dv. In addition, in this embodiment, the first lens 41d is a cylindrical lens having a central axis parallel to the horizontal direction Dh, and the second lens 42d is a cylindrical lens having a central axis parallel to the vertical direction Dv, so that the focal position of the focusing optical system 40d in the horizontal direction Dh and the focal position in the vertical direction Dv can be adjusted independently of each other.

[0029] E. Fifth embodiment: As shown in FIGS. 13 and 14 , the distance measuring device 10e of the fifth embodiment differs from the first embodiment in the configurations of the irradiation unit 20e and the diaphragm unit 50e. The remaining configurations are the same as those of the first embodiment. As shown in FIG. 13 , in this embodiment, the irradiation unit 20e includes a vertical cavity surface-emitting laser (VCSEL) as a light-emitting element and emits multiple dot-like irradiation light beams Lo aligned along the vertical direction Dv. As shown in FIG. 14 , the aperture 55e of the diaphragm unit 50e is formed by multiple through-holes aligned along the vertical direction Dv. Each through-hole has a circular shape. In this embodiment, the direction in which the multiple through-holes are aligned is referred to as the longitudinal direction of the aperture 55e, and the direction perpendicular to the longitudinal direction and the central axis of the through-hole is referred to as the lateral direction of the aperture 55e. As with the first embodiment, the distance measuring device 10e of the fifth embodiment described above can enhance the light intensity resolution while suppressing a decrease in the optical signal-to-noise ratio, and can suppress a decrease in the position resolution in the vertical direction Dv. The distance measuring device 10e of the fifth embodiment may include the diaphragm unit 50 similar to that of the first embodiment, instead of the diaphragm unit 50e described above. The distance measuring device 10e may include the condensing optical system 40b to 40d of any one of the second, third, and fourth embodiments, instead of the condensing optical system 40 similar to that of the first embodiment.

[0030] F. Other Embodiments: (F1) In the distance measuring devices 10 to 10e of the above-described embodiments, the focusing optical system 40 to 40d is composed of two lenses 41 to 41d, 42 to 42d. Alternatively, the focusing optical system 40 to 40d may be composed of a single lens having different refractive powers in the horizontal direction Dh and the vertical direction Dv. The focusing optical system 40 may be composed of, for example, a single toroidal lens, a single toric lens, or a single anamorphic lens. In this case, the focusing optical system 40 to 40d can be made smaller than when the focusing optical system 40 to 40d is composed of multiple lenses.

[0031] (F2) The distance measuring devices 10 to 10e of the above-described embodiments include a scanning unit 30 that scans the irradiated light Lo along the horizontal direction Dh. In contrast, the distance measuring devices 10 to 10e do not necessarily need to include the scanning unit 30.

[0032] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features in the embodiments can be appropriately replaced or combined to solve some or all of the above-described problems or to achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Form 1] The distance measuring device (10) comprises: an emitting unit (20) that emits illumination light (Lo); a light receiving unit (60) having a light receiving surface (61) that receives incident light (Li) including reflected light of the illumination light, with one pixel (65) being composed of a plurality of single-photon avalanche diodes (68); an aperture unit (50) that has an opening (55) through which the incident light entering the light receiving unit passes and limits the amount of the incident light that passes; and an optical system (40) that has different refractive powers in the longitudinal direction and the lateral direction of the opening, and that focuses the incident light on the light receiving surface in the longitudinal direction and focuses the incident light on the opening in the lateral direction. [Form 2] The distance measuring device described in form 1 may also include a scanning unit (30) that has a mirror (31) that reflects the irradiated light and the incident light, and that rotates the mirror around a rotation axis (RX) parallel to the longitudinal direction of the opening, thereby scanning the irradiated light emitted from the light emitting unit along the short direction and making the incident light enter the optical system. [Form 3] In the distance measuring device according to the first or second aspect, the length of one pixel in the short-side direction of the opening may be longer than the length of one pixel in the long-side direction of the opening. [Form 4] In the distance measuring device according to any one of the first to third aspects, the light emitting section may irradiate the irradiation light in a line shape along the longitudinal direction of the opening. [Form 5] In the distance measuring device according to any one of the first to third aspects, the light emitting section may emit the irradiation light in the form of a plurality of dots arranged along the longitudinal direction of the opening. [Form 6] In the distance measuring device according to any one of the first to fifth aspects, the optical system may include a spherical lens and a cylindrical lens. [Form 7] In the distance measuring device according to any one of the first to fifth embodiments, the optical system may include a cylindrical lens having a central axis parallel to the longitudinal direction of the opening, and a cylindrical lens having a central axis parallel to the lateral direction of the opening. [Form 8] In the distance measuring device according to any one of the first to fifth aspects, the optical system may include a toroidal lens. [Explanation of symbols]

[0033] 10... distance measuring device, 20... light emitting unit, 30... scanning unit, 31... mirror, 32... motor, 33... rotation angle sensor, 40... light collecting optical system, 41... first lens, 42... second lens, 50... diaphragm unit, 55... opening, 60... light receiving unit, 61... light receiving surface, 65... pixel, 68... light receiving element, 70... control unit, 80... housing

Claims

1. A distance measuring device (10), a light emitting unit (20) that emits irradiation light (Lo); a light receiving unit (60) having a light receiving surface (61) that receives incident light (Li) including reflected light of the irradiation light, and one pixel (65) is composed of a plurality of single-photon avalanche diodes (68); a diaphragm section (50) having an opening (55) through which the incident light incident on the light receiving section passes and limiting the amount of the incident light passing through; an optical system (40) having different refractive powers in the longitudinal direction of the opening and the lateral direction of the opening, which focuses the incident light on the light receiving surface in the longitudinal direction and focuses the incident light on the opening in the lateral direction; A distance measuring device comprising:

2. 2. The distance measuring device according to claim 1, A distance measuring device comprising a scanning unit (30) having a mirror (31) that reflects the irradiated light and the incident light, and that rotates the mirror around a rotation axis (RX) parallel to the longitudinal direction of the opening, thereby scanning the irradiated light emitted from the light-emitting unit along the short direction and making the incident light enter the optical system.

3. 2. The distance measuring device according to claim 1, A distance measuring device, wherein the length of one pixel in the short direction of the opening is longer than the length of one pixel in the long direction of the opening.

4. 2. The distance measuring device according to claim 1, The light emitting unit emits the linear irradiation light along the longitudinal direction of the opening.

5. 2. The distance measuring device according to claim 1, The light emitting unit emits the irradiation light in the form of a plurality of dots aligned along the longitudinal direction of the opening.

6. 2. The distance measuring device according to claim 1, The optical system of the distance measuring device includes a spherical lens and a cylindrical lens.

7. 2. The distance measuring device according to claim 1, A distance measuring device, wherein the optical system includes a cylindrical lens having a central axis parallel to the longitudinal direction of the opening, and a cylindrical lens having a central axis parallel to the lateral direction of the opening.

8. 2. The distance measuring device according to claim 1, The optical system of the distance measuring device includes a toroidal lens.

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