Optical sensors, light receiving modules

Abstract

To provide an optical sensor capable of securing a dynamic range while achieving resolution.SOLUTION: An optical sensor comprises: a light-receiving system that, with a first reference surface S1 and a second reference surface S2 which are orthogonal to each other as reference, applies positive power different each other on the reference surfaces S1, S2 to a longitudinal reflection beam along the first reference surface S1, and the more attenuates transmittance of the reflection beam, the farther from an optical axis ROA along the second reference surface S2; an aperture unit forming along the first reference surface S1, an optical aperture positioned at a focal point on the second reference surface S2 by the light-receiving system and transmitting the reflection beam subjected to optical action by the light-receiving system; and a light-receiving unit receiving the reflection beam transmitting through the optical aperture by a plurality of light receiving elements positioned at a focal point on the first reference surface S1 by the light-receiving system and arrayed two-dimensionally along the reference surfaces S1, S2.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to an optical sensor and a light receiving module applied thereto. [Background technology]

[0002] The optical sensor disclosed in Patent Document 1 performs sensing by irradiating an irradiation beam toward a sensing area in the outside world and receiving a beam that is reflected from the sensing area in response to the irradiation beam. [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] The optical sensor disclosed in Patent Document 1 ensures a dynamic range by transmitting reflected beams of illumination beams emitted in a dot pattern from multiple light sources through multiple openings in an aperture and receiving them at multiple light receiving elements in a light receiving unit. However, the light receiving area on the array surface where each light receiving element is arranged, which can receive the reflected beam, is divided into dots corresponding to each illumination beam, resulting in a decrease in resolution.

[0005] An object of the present disclosure is to provide an optical sensor that ensures a dynamic range while also achieving high resolution, and a light receiving module therefor. [Means for solving the problem]

[0006] The technical means of the present disclosure for solving the problems will be described below. Note that the claims and the reference characters in parentheses in this section indicate the correspondence with the specific means described in the embodiments described later in detail, and do not limit the technical scope of the present disclosure.

[0007] A first aspect of the present disclosure is An optical sensor that performs sensing by irradiating a linear irradiation beam (IB) toward a sensing area (SA) in the outside world and receiving a reflected beam (RB) from the sensing area in response to the irradiation beam on an optical axis (ROA), a light receiving optical system (42, 2042) that applies different positive powers on the first reference surface and the second reference surface to a longitudinal reflected beam along the first reference surface, using a first reference surface (S1) and a second reference surface (S2) that are orthogonal to each other as references, and that attenuates the transmittance of the reflected beam as it moves away from the optical axis along the second reference surface; an aperture unit (410) that forms an optical aperture (411) along the first reference surface, the optical aperture being aligned with a focal point (PF2) on the second reference surface by the light receiving optical system and that transmits the reflected beam that has been optically acted on by the light receiving optical system; The optical sensor includes a light receiving unit (45, 3045) that receives the reflected beam that has passed through the optical aperture using a plurality of light receiving elements (46) that are aligned with a focal point (PF1) on a first reference plane by the light receiving optical system and are arranged in a two-dimensional direction along the first reference plane and the second reference plane.

[0008] A second aspect of the present disclosure is applied to the optical sensor of the first aspect, The light receiving module is configured by packaging a light receiving optical system together with a light receiving unit and an aperture unit.

[0009] According to these first and second aspects, the aperture unit, which is aligned with the focal point on the second reference plane of the light receiving optical system, forms an optical aperture along the first reference plane that transmits the reflected beam that has been optically affected by the light receiving optical system. The light receiving unit, which is aligned with the focal point on the first reference plane of the light receiving optical system, receives the reflected beam that has passed through the optical aperture using a plurality of light receiving elements arranged in a two-dimensional direction along the first and second reference planes. This allows the light receiving area that can receive the reflected beam that has passed through the optical aperture in response to the linear irradiation beam to be continuous in the light receiving unit in a direction along the first reference plane. This makes it possible to ensure the resolution of the light receiving unit.

[0010] Furthermore, the light-receiving optical system according to the first and second aspects attenuates the transmittance of the reflected beam as it moves away from the optical axis along the second reference plane. As the reflected beam, which has been subjected to this transmittance attenuation effect, passes through the optical opening of the aperture unit, the light is received by the light-receiving unit with an intensity distribution along the second reference plane while suppressing contamination of external light along the first reference plane. This makes it possible to ensure a dynamic range that is compatible with the resolution of the light-receiving unit. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing the overall configuration of an optical sensor according to a first embodiment; [Figure 2] FIG. 2 is a schematic diagram showing an irradiation unit and a scanning unit according to the first embodiment. [Figure 3] FIG. 2 is a schematic diagram showing a light receiving unit and a scanning unit according to the first embodiment. [Figure 4] FIG. 2 is an enlarged schematic view showing an irradiation unit according to the first embodiment. [Figure 5] FIG. 2 is an enlarged schematic view showing a light receiving section according to the first embodiment. [Figure 6] FIG. 2 is an enlarged schematic view showing a light receiving section according to the first embodiment. [Figure 7] 4 is a graph showing characteristics of a light receiving unit according to the first embodiment. [Figure 8]FIG. 2 is an enlarged schematic view showing a light receiving section according to the first embodiment. [Figure 9] FIG. 2 is a schematic diagram showing a light receiving section according to the first embodiment. [Figure 10] FIG. 2 is a schematic diagram showing a light receiving section according to the first embodiment. [Figure 11] 4 is a graph showing characteristics of a light receiving unit according to the first embodiment. [Figure 12] FIG. 10 is a schematic diagram showing the overall configuration of an optical sensor according to a second embodiment. [Figure 13] FIG. 10 is a schematic diagram showing a light receiving unit and a scanning unit according to a second embodiment. [Figure 14] FIG. 10 is a schematic diagram showing the overall configuration of an optical sensor according to a third embodiment. [Figure 15] FIG. 10 is a schematic diagram showing a light receiving unit and a scanning unit according to a third embodiment. [Figure 16] FIG. 10 is an enlarged schematic view showing a light receiving section according to a third embodiment. [Figure 17] FIG. 10 is a schematic diagram showing the overall configuration of an optical sensor according to a fourth embodiment. [Figure 18] FIG. 10 is a schematic diagram showing a light receiving unit and a scanning unit according to a fourth embodiment. [Figure 19] FIG. 10 is a schematic diagram showing the overall configuration of an optical sensor according to a fifth embodiment. [Figure 20] FIG. 13 is a schematic diagram showing a light receiving unit and a scanning unit according to a fifth embodiment. [Figure 21] FIG. 10 is a schematic diagram showing a light receiving unit and a scanning unit according to a modified example of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, multiple embodiments of the present disclosure will be described with reference to the drawings. Note that corresponding components in each embodiment are designated by the same reference numerals, and redundant description may be omitted. Furthermore, when only a portion of the configuration is described in each embodiment, the configuration of another previously described embodiment may be applied to the remaining portions of the configuration. Furthermore, in addition to the combinations of configurations explicitly stated in the description of each embodiment, configurations of multiple embodiments may be partially combined together even if not explicitly stated, provided that there is no particular problem with the combination.

[0013] (First embodiment) 1, an optical sensor 10 according to a first embodiment of the present disclosure is a LiDAR (Light Detection and Ranging / Laser Imaging Detection and Ranging) mounted on a vehicle as a moving body. In the following description, unless otherwise specified, the directions indicated by front, rear, up, down, left, and right are defined with respect to the vehicle on a horizontal plane. Furthermore, the horizontal direction indicates a tangential direction to the horizontal plane, and the vertical direction indicates a direction perpendicular to the horizontal plane.

[0014] The optical sensor 10 is disposed in at least one location on the vehicle, such as the front, left and right sides, rear, or upper roof. The optical sensor 10 irradiates a beam IB toward a sensing area SA in the environment outside the vehicle, which corresponds to the location where the optical sensor 10 is disposed. The optical sensor 10 performs sensing by receiving a reflected beam RB that is reflected by a target within the sensing area SA from the irradiated beam IB. Therefore, light in the near-infrared range, which is difficult for people in the outside world to see, is usually selected for the irradiated beam IB that becomes the reflected beam RB.

[0015] The optical sensor 10 senses a target within the sensing area SA by receiving the reflected beam RB. Here, sensing of the target refers to at least one of the following: the distance from the optical sensor 10 to the target, the direction in which the target is located, and the reflection intensity of the reflected beam RB from the target. In particular, the target to be sensed by the optical sensor 10 applied to a vehicle may be at least one of moving objects such as pedestrians, cyclists, non-human animals, and other vehicles. Furthermore, the target to be sensed by the optical sensor 10 applied to a vehicle may be at least one of stationary objects such as guardrails, road signs, roadside structures, and fallen objects on the road.

[0016] In the optical sensor 10, a three-dimensional Cartesian coordinate system is defined by three mutually orthogonal axes: an X-axis, a Y-axis, and a Z-axis. In particular, in the optical sensor 10 applied to a vehicle, the Y-axis direction is set to the vertical direction of the vehicle. Furthermore, in the optical sensor 10 applied to a vehicle, the X-axis and the Z-axis direction are set to different horizontal directions of the vehicle. Therefore, as shown in FIGS. 1, 5, and 6, a first reference plane S1 serving as a reference in the optical sensor 10 is defined as a so-called tangential plane, which is a YZ plane including the Y-axis and the Z-axis. Furthermore, as shown in FIGS. 2, 3, 5, and 6, a second reference plane S2 serving as a reference in the optical sensor 10 and perpendicular to the first reference plane S1 is defined as an XZ plane including the X-axis and the Z-axis. Furthermore, as shown in FIGS. 4 to 6, a third reference plane S3 serving as a reference in the optical sensor 10 and perpendicular to the first reference plane S1 and the second reference plane S2 is defined as an XY plane including the X-axis and the Y-axis.

[0017] 1 to 3, optical sensor 10 includes a housing 11, an irradiation unit 21, a scanning unit 31, a light receiving unit 41, and a control unit 51. As shown in FIG. 1, housing 11 forms the exterior of optical sensor 10. Housing 11 includes a light-shielding case 12 and a cover panel 15. Note that in FIG. 1, the left side of the dashed dotted line in the Y-axis direction (the cover panel 15 side) actually illustrates a cross section perpendicular to the right side of the dashed dotted line (the irradiation unit 21 side and the light receiving unit 41 side).

[0018] The light-shielding case 12 is formed from a light-shielding material such as synthetic resin or metal. The light-shielding case 12 has a box-like shape as a whole. The light-shielding case 12 is constructed from a single component or a combination of multiple components. The light-shielding case 12 houses an irradiation unit 21, a scanning unit 31, and a light-receiving unit 41 inside. Furthermore, the light-shielding case 12 may house a control unit 51 inside, as shown in FIG. 1.

[0019] The cover panel 15 is formed mainly from a base material such as synthetic resin or glass that is translucent in the near-infrared range. The cover panel 15 has a flat or curved shape as a whole. The cover panel 15 completely covers the through-hole provided in the light-shielding case 12.

[0020] As shown in FIGS. 1 and 2, the irradiation section 21 includes a light-projecting unit 22 and an irradiation optical system 26. The light-projecting unit 22 is disposed within the housing 11 and emits laser light in the near-infrared region, which becomes the irradiation beam IB. To this end, as shown in FIG. 4, the light-projecting unit 22 has a plurality of laser oscillation elements 24 on a light-projection array substrate. The laser oscillation elements 24 are arranged one-dimensionally in a single row in the Y-axis direction. Each laser oscillation element 24 is, for example, an edge-emitter laser or a surface-emitting laser. Each laser oscillation element 24 emits laser light, which becomes part of the irradiation beam IB.

[0021] The light-projecting unit 22 has a light-projection window 25 formed on one side of the light-projection array substrate, the light-projection window 25 being defined by a rectangular outline elongated in the Y-axis direction. The light-projection window 25 is constructed as a collection of laser oscillation apertures in each laser oscillation element 24. As a result, the laser light output from the laser oscillation aperture of each laser oscillation element 24 is projected from the light-projection window 25 as a virtual linear irradiation beam IB elongated in the Y-axis direction in the sensing area SA shown in FIG. 1. The irradiation beam IB in the housing 11 may include non-light-emitting portions corresponding to the arrangement intervals of the laser oscillation elements 24 in the Y-axis direction. Even in this case, it is preferable that a linear irradiation beam IB from which non-light-emitting portions are macroscopically eliminated is formed in the sensing area SA by the optical action of the irradiation optical system 26 described later.

[0022] 1 and 2, the irradiation optical system 26 is disposed within the housing 11 between the light-projecting unit 22 and the scanning mirror 32 of the scanning unit 31. The irradiation optical system 26 projects the irradiation beam IB from the light-projecting unit 22 toward the scanning mirror 32. To achieve this, the irradiation optical system 26 guides the irradiation beam IB projected from the light-projecting unit 22 to the scanning mirror 32 on an irradiation optical axis IOA in the Z-axis direction. To achieve this light guidance, the irradiation optical system 26 has an irradiation lens 27 held by the light-shielding case 12. The irradiation lens 27 is formed mainly from a lens substrate that is translucent in the near-infrared range, such as synthetic resin or glass.

[0023] Here, particularly in the first embodiment, a pair of a front-stage cylindrical lens 27a and a rear-stage rotationally symmetric lens 27b is selected for the illumination lens 27. The cylindrical lens 27a is a plano-convex cylindrical lens whose generatrix direction is the X-axis direction and whose positive power direction is the Y-axis direction. The rotationally symmetric lens 27b is a biconvex lens whose positive power direction is an arbitrary direction around the Z-axis. The illumination optical system 26 applies different positive powers in the Y-axis direction and the X-axis direction to the illumination beam IB by combining the cylindrical lens 27a and the rotationally symmetric lens 27b.

[0024] 1 to 3, the scanning unit 31 includes a scanning mirror 32 and a scanning motor 35. The scanning mirror 32 is disposed within the housing 11, spanning from between the cover panel 15 and the irradiation optical system 26 to between the cover panel 15 and the light-receiving optical system 42 of the light-receiving unit 41. The scanning mirror 32 scans the irradiation beam IB projected from the irradiation optical system 26 toward the sensing area SA, and reflects a reflected beam RB from the sensing area SA in response to the irradiation beam IB toward the light-receiving optical system 42.

[0025] The scanning mirror 32 is formed mainly from a base material such as synthetic resin or glass. The scanning mirror 32 has a flat plate shape as a whole. A reflective film made of, for example, aluminum, silver, or gold is vapor-deposited on one side of the mirror base material, thereby forming a reflective surface 33 with a rectangular outline extending in the Y-axis direction.

[0026] The scanning mirror 32 has a rotation axis 34 that is rotatably held by the light-shielding case 12. The rotation axis 34 is disposed to extend in the Y-axis direction, along which the reflective surface 33 is longitudinal. The scanning mirror 32 rotates around a rotation center line CM that is set to extend in the Y-axis direction, thereby adjusting the normal direction of the reflective surface 33 to be about the rotation center line CM. Therefore, the scanning mirror 32 is capable of oscillating within a finite rotation angle range DR, for example, by a mechanical or electrical stopper. This restricts the irradiation beam IB reflected by the scanning mirror 32 so that it does not deviate from the outer contour of the cover panel 15.

[0027] The scanning mirror 32 is provided in common to the irradiation unit 21 and the light receiving unit 41. The reflecting surface 33 of the scanning mirror 32 is provided in common to the irradiation beam IB and the reflected beam RB. The reflecting surface 33 has a portion that reflects the irradiation beam IB and a portion that reflects the reflected beam RB that are configured to be separated from each other or to at least partially overlap each other.

[0028] 1 and 2, the illumination beam IB is reflected by the reflecting surface 33, the normal of which is adjusted in accordance with the rotational drive of the scanning mirror 32, and passes through the cover panel 15 to temporally and spatially scan the sensing area SA. The scanning of the illumination beam IB over the sensing area SA is substantially limited to scanning in the horizontal direction in accordance with the rotational drive of the scanning mirror 32 about the rotation center line CM. As a result, the rotational angle range DR of the scanning mirror 32 defines the horizontal angle of view in the sensing area SA.

[0029] The illumination beam IB is reflected by a target present in the sensing area SA, and becomes a reflected beam RB that returns to the optical sensor 10. The reflected beam RB passes through the cover panel 15 again and is incident on the reflecting surface 33 of the scanning mirror 32. Here, the speeds of the illumination beam IB and the reflected beam RB are sufficiently greater than the rotational speed of the scanning mirror 32. As a result, the reflected beam RB is reflected by the reflecting surface 33 of the scanning mirror 32, which has approximately the same rotation angle as the illumination beam IB, and can be assumed to be guided to the light-receiving optical system 42 in a direction opposite to that of the illumination beam IB.

[0030] As shown in FIG. 1 , the scanning motor 35 is disposed around the scanning mirror 32 within the housing 11. The scanning motor 35 is, for example, a voice coil motor, a brushed DC motor, or a stepping motor. The output shaft of the scanning motor 35 is coupled directly to the rotating shaft 34 of the scanning mirror 32, or indirectly via a drive mechanism such as a reducer. The scanning motor 35 is held by the light-shielding case 12 so that the rotating shaft 34 can be rotated together with the output shaft. The scanning motor 35 rotates the rotating shaft 34 within a rotation angle range DR.

[0031] 1 and 3, the light receiving section 41 includes a light receiving optical system 42 and a light receiving unit 45. The light receiving optical system 42 is disposed between the scanning mirror 32 and the light receiving unit 45 inside the housing 11. The light receiving optical system 42 is positioned below the irradiation optical system 26 in the Y-axis direction.

[0032] The light-receiving optical system 42 forms an image of the reflected beam RB from the scanning mirror 32 on the light-receiving unit 45. To this end, the light-receiving optical system 42 causes the reflected beam RB reflected from the scanning mirror 32 to be received by the light-receiving unit 45 on a light-receiving optical axis ROA in the Z-axis direction. At this time, the reflected beam RB is a linear beam elongated in the Y-axis direction and in the near-infrared region corresponding to the irradiation beam IB, and is subjected to light guiding action along the light-receiving optical axis ROA over the entire rotation angle range DR of the scanning mirror 32. Therefore, the light-receiving optical system 42 has a light-receiving lens 43 held by the light-shielding case 12. The light-receiving lens 43 is formed primarily from a lens substrate such as synthetic resin or glass that is translucent in the near-infrared region.

[0033] In particular, the light receiving lens 43 of the first embodiment is a pair consisting of a rotationally symmetric lens 43a at the front and a cylindrical lens 43b at the rear. The rotationally symmetric lens 43a is a biconvex lens whose positive power direction is in any direction around the Z axis. The cylindrical lens 43b is a plano-convex cylindrical lens whose generatrix direction is the Y axis and whose positive power direction is the X axis. The light receiving optical system 42 applies different positive powers in the Y axis direction and the X axis direction to the reflected beam RB elongated in the Y axis direction by combining the rotationally symmetric lens 43a and the cylindrical lens 43b. That is, using a first reference plane S1 and a second reference plane S2 that are orthogonal to each other as references, the light receiving optical system 42 applies different positive powers on the first reference plane S1 and the second reference plane S2 to the reflected beam RB elongated along the first reference plane S1.

[0034] The light-receiving unit 45 is positioned below the light-emitting unit 22 in the Y-axis direction within the housing 11. The light-receiving unit 45 receives the reflected beam RB formed by the light-receiving optical system 42 and outputs a light-receiving signal. To this end, as shown in FIG. 5, the light-receiving unit 45 has a plurality of light-receiving elements 46 on a light-receiving array substrate. The light-receiving elements 46 are two-dimensionally arranged in multiple rows in the Y-axis direction and the X-axis direction. That is, the light-receiving elements 46 are arranged two-dimensionally along the first reference plane S1 and the second reference plane S2.

[0035] 1, 3, and 5, the light-receiving surface of the light-receiving unit 45, on which the light-receiving elements 46 are arranged and which receives the reflected beam RB, is formed on one side of the light-receiving array substrate as an array surface 47 having a rectangular outline perpendicular to the Z-axis direction and elongated in the Y-axis direction. That is, using a third reference plane S3 perpendicular to the first reference plane S1 and the second reference plane S2 as a reference, the array surface 47 of the light-receiving elements 46 in the light-receiving unit 45 is positioned in an orientation along the third reference plane S3. Such an array surface 47 is constructed as a collection of the incident surfaces of the light-receiving elements 46.

[0036] In the light receiving unit 45, each light receiving element 46 is mainly composed of a single photon avalanche diode (SPAD). Therefore, in the light receiving unit 45, a plurality of light receiving pixels 48, each enclosed by a thick line in FIG. 5 as a unit for reading out a light receiving signal from each light receiving element 46, are constructed so that each pixel includes a set number of light receiving elements 46. Here, each light receiving pixel 48 is constructed from a different number of light receiving elements 46 in the Y-axis direction and the X-axis direction. In particular, in the first embodiment, each light receiving pixel 48 is linearly arranged in a single row in the Y-axis direction. That is, on the array surface 47 of the light receiving unit 45, each light receiving pixel 48 is linearly arranged along the first reference plane S1.

[0037] In the light receiving unit 45 configured as above, the signal value of the light receiving signal changes for each light receiving pixel 48 in accordance with the number of responses of the light receiving elements 46 that respond to the reflected beam RB. In the light receiving unit 45, which bundles such light receiving signals into groups of a set number of light receiving elements 46 for each light receiving pixel 48, it is possible to increase the dynamic range by using a detailed configuration that will be described later. Therefore, as shown in Figures 1 and 3, the light receiving unit 45 has an output circuit 49 for sampling the light receiving signals read out from the set number of light receiving elements 46 for each light receiving pixel 48 and outputting them to the control unit 51.

[0038] The control unit 51 shown in FIG. 1 controls the sensing of targets within the sensing area SA. The control unit 51 is mainly composed of at least one computer including a processor and a memory. The control unit 51 may be entirely housed within the housing unit 11 (example of FIG. 1). The control unit 51 may be entirely located in a vehicle outside the housing unit 11. The control device 1 may be distributed across the housing unit 11 and the vehicle outside the housing unit 11.

[0039] The control unit 51 is connected to the light-projecting unit 22, the scanning motor 35, and the light-receiving unit 45. The control unit 51 controls the readout and output of the light-receiving signal in the light-receiving unit 45 while rotating the scanning mirror 32 in synchronization with the irradiation timing of the irradiation beam IB from the light-projecting unit 22. As a result, the control unit 51 generates sensing data such as image data by sensing targets in the sensing area SA based on the light-receiving signal output from the light-receiving unit 45.

[0040] (Detailed configuration) Next, the detailed configuration of the light receiving section 41 will be described.

[0041] 1, 3, and 6, the light-receiving optical system 42 in the light-receiving section 41 further includes an apodization element 420. The apodization element 420 is disposed between the front rotationally symmetric lens 43a and the rear cylindrical lens 43b in the light-receiving optical system 42 inside the housing 11. The apodization element 420 is aligned at a conjugate point conjugate to the array surface 47 of each light-receiving element 46 in the light-receiving unit 45.

[0042] The apodization element 420 is a flat apodization filter endowed with optical properties that distribute transmittance in the near-infrared range. The apodization element 420 is formed with a transmittance distribution in the near-infrared range, primarily made of a filter substrate such as synthetic resin or glass. The apodization element 420 is held in the light-shielding case 12, so that it extends perpendicular to the Z-axis direction. In other words, the apodization element 420 in the light-receiving optical system 42 is positioned along the third reference plane S3.

[0043] As shown in Figures 6 and 7, in the apodization element 420, the transmittance of the reflected beam RB decreases in a Gaussian distribution pattern from the center to the outer periphery on the light-receiving optical axis ROA in the X-axis direction. That is, the apodization element 420 in the light-receiving optical system 42 attenuates the transmittance of the reflected beam RB the farther it is from the light-receiving optical axis ROA along the second reference plane S2. Here, Figure 6 illustrates the transmittance of the reflected beam RB in a grayscale that becomes lighter as the transmittance is attenuated. However, in the apodization element 420 of the first embodiment, the frame-shaped outermost periphery 421 shown with cross-hatching in Figure 6 (see also the white portion in Figures 1 and 3) is covered with a light-shielding film, thereby limiting the transmittance of the reflected beam RB to essentially zero.

[0044] 1 and 3, the light receiving optical system 42 in the light receiving section 41 further includes a bandpass element 422. The bandpass element 422 is disposed in the housing 11 after the cylindrical lens 43b of the light receiving optical system 42 and before the light receiving unit 45.

[0045] The bandpass element 422 is a flat bandpass filter that has optical properties that limit the transmission of the reflected beam RB, which has been optically affected by the lenses 43a and 43b in the light-receiving optical system 42, to the near-infrared region, which is the set band of the illumination beam IB. The bandpass element 422 is formed primarily from a filter substrate, such as synthetic resin or glass, that is translucent in the near-infrared region but has virtually zero transmittance for other bands. The bandpass element 422 is held by the light-shielding case 12, so that it extends perpendicular to the Z-axis direction. That is, the bandpass element 422 in the light-receiving optical system 42 is positioned along a third reference plane S3 (see FIGS. 5 and 6).

[0046] 1, 3, 8, and 9, the light receiving section 41 is further provided with an aperture unit 410. The aperture unit 410 is disposed within the housing 11 between the bandpass element 422, which is located at the final stage of the light receiving optical system 42, and the light receiving unit 45. As shown in FIG. 9, the aperture unit 410 is positioned as a focal point PF2 on the second reference plane S2 by the light receiving optical system 42, and particularly in the first embodiment, as a composite focal point of the parallel beams on the same plane S2 by the lenses 43a and 43b.

[0047] 1, 3, 8, and 9, aperture unit 410 is a flat optical diaphragm having optical aperture 411 partially imparted with light-transmitting properties in the near-infrared range. Such aperture unit 410 may be formed mainly from a substrate that is transmissive in the near-infrared range, such as synthetic resin or glass, with the surface of the transmissive substrate coated with a light-shielding film such as a metal film, resist film, dielectric film, or coating film on the outer periphery of optical aperture 411. Aperture unit 410 may be formed mainly from a light-shielding substrate, such as synthetic resin or metal, with a transmittance of essentially zero on the outer periphery of optical aperture 411 that penetrates the light-shielding substrate.

[0048] Aperture unit 410 is held by light-tight case 12, and thus extends perpendicular to the Z-axis direction. That is, aperture unit 410 in light-receiving optical system 42 is positioned along third reference plane S3. Reflected beam RB, which has been subjected to optical effects from elements 43a, 420, 43b, and 422 in light-receiving optical system 42, enters optical opening 411 formed by aperture unit 410. Optical opening 411 transmits the incident reflected beam RB and emits it toward light-receiving unit 45 in the subsequent stage.

[0049] The optical aperture 411 in the aperture unit 410 has a rectangular contour elongated in the Y-axis direction. That is, the optical aperture 411 in the aperture unit 410 is formed along the first reference plane S1. If the size Δa (see FIG. 8) of the optical aperture 411 in the X-axis direction along the second reference plane S2 is defined as an allowable distance, the aperture unit 410 shown in FIG. 9 is positioned within the allowable distance on both sides of the focal point PF2 on the second reference plane S2 by the light receiving optical system 42 along the light receiving optical axis ROA. The size Δa, which is the allowable distance under this definition, is preferably set to be equal to or greater than the depth of focus on the second reference plane S2. Furthermore, the aperture unit 410 may be positioned within the depth of focus on the second reference plane S2 on both sides of the focal point PF2 on the second reference plane S2 by the light receiving optical system 42 along the light receiving optical axis ROA.

[0050] As shown in FIG. 10 , in the light receiving section 41, the array surface 47 of the light receiving unit 45 is positioned at a focal point PF1 on the first reference plane S1 by the light receiving optical system 42, particularly in the first embodiment, at a combined focal point of the parallel beams on the same plane S1 by the lenses 43 a and 43 b. If the size Δp (see FIG. 5 ) of the light receiving pixels 48 in the X-axis direction along the second reference plane S2 is defined as an allowable distance, the array surface 47 is positioned within the allowable distance on both sides of the focal point PF1 on the first reference plane S1 by the light receiving optical system 42 along the light receiving optical axis ROA. The size Δp, which is the allowable distance under this definition, is preferably set to be equal to or greater than the depth of focus on the first reference plane S1. Furthermore, the array surface 47 may be positioned within the depth of focus on the same plane S1 on both sides of the focal point PF1 on the first reference plane S1 by the light receiving optical system 42 along the light receiving optical axis ROA.

[0051] With this configuration, in the light receiving unit 45, the reflected beam RB that has passed through the optical opening 411 of the aperture unit 410 is received on the array surface 47 with an intensity distribution that corresponds to the transmittance distribution of the apodization element 420, as shown in Figure 11. Therefore, in the X-axis direction along the second reference plane S2, the received light intensity distribution of the reflected beam RB is 1 / e of the peak intensity. 2 The light-receiving area RA defined in the range where p is the pixel size Δp (see also FIG. 5) is preferably adjusted to be smaller than the effective area EA that is effective on the array surface 47 according to the pixel size Δp. Furthermore, based on this distribution of received light intensity, the reflected beam RB with peak intensity is preferably used for sensing long-distance targets or low-reflectivity targets, while the base intensity near both ends of the light-receiving area RA is preferably used for sensing short-distance targets or high-reflectivity targets.

[0052] (Action and effect) The effects of the first embodiment described above will be explained below.

[0053] According to the first embodiment, the aperture unit 410, which is aligned with the focal point PF2 on the second reference plane S2 of the light receiving optical system 42, forms an optical opening 411 along the first reference plane S1, which transmits the reflected beam RB that has been optically affected by the light receiving optical system 42. The light receiving unit 45, which is aligned with the focal point PF1 on the first reference plane S1 of the light receiving optical system 42, receives the reflected beam RB that has passed through the optical opening 411 using a plurality of light receiving elements 46 that are arranged in a two-dimensional direction along the first reference plane S1 and the second reference plane S2. This allows the light receiving area RA, which can receive the reflected beam RB that has passed through the optical opening 411 in response to the linear irradiation beam IB, to be continuous in the Y-axis direction of the light receiving unit 45 along the first reference plane S1. This makes it possible to ensure the resolution of the light receiving unit 45.

[0054] Moreover, the light receiving optical system 42 according to the first embodiment attenuates the transmittance of the reflected beam RB the farther it is from the light receiving optical axis ROA along the second reference plane S2. As the reflected beam RB that has been subjected to this transmittance attenuation effect passes through the optical opening 411 of the aperture unit 410, it can be received by the light receiving unit 45 with an intensity distribution in the X axis direction along the second reference plane S2 while having external light contamination suppressed in the Y axis direction along the first reference plane S1. This makes it possible to ensure a dynamic range that is compatible with the resolution of the light receiving unit 45.

[0055] According to the first embodiment, the apodization element 420, which attenuates the transmittance of the reflected beam RB as it moves away from the light-receiving optical axis ROA along the second reference plane S2, is positioned at a conjugate point with respect to the array surface 47 of the light-receiving elements 46 in the light-receiving unit 45. This allows the light-receiving area RA of the reflected beam RB, which has an intensity distribution in the X-axis direction along the second reference plane S2, to be accurately formed on the array surface 47 of the light-receiving elements 46. This makes it possible to increase the reliability of the effect of ensuring the dynamic range.

[0056] According to the first embodiment, the size Δa of the optical aperture 411 in the X-axis direction along the second reference plane S2 is set as an allowable distance, and the aperture unit 410 is positioned within the allowable distance along the light-receiving optical axis ROA from the focal point PF2 on the second reference plane S2 by the light-receiving optical system 42. This allows the aperture unit 410 to accurately exert an optical effect of suppressing external light contamination in the Y-axis direction along the first reference plane S1 and distributing the intensity of the reflected beam RB in the X-axis direction along the second reference plane S2. This makes it possible to increase the reliability of the effect of ensuring a dynamic range.

[0057] The bandpass element 422 of the light receiving optical system 42 according to the first embodiment limits the transmission of the reflected beam RB to a set band of the irradiation beam IB. This allows not only the aperture unit 410 to suppress external light contamination in the Y-axis direction along the first reference plane S1, but also the bandpass element 422 to suppress external light contamination by limiting transmission, for the reflected beam RB, which has an intensity distribution in the X-axis direction along the second reference plane S2. This makes it possible to increase the reliability of the effect of ensuring a dynamic range.

[0058] According to the first embodiment, each of the plurality of light-receiving pixels 48, which are units for reading out light-receiving signals, includes a set number of light-receiving elements 46. The array surface 47 of the light-receiving elements 46 in the light-receiving unit 45 is positioned within the allowable distance along the light-receiving optical axis ROA from the focal point PF1 on the first reference surface S1 of the light-receiving optical system 42, with the size Δp of the light-receiving pixel 48 in the X-axis direction along the second reference surface S2 being the allowable distance. This allows light-receiving areas RA capable of receiving the focused reflected beam RB to be formed continuously in the X-axis direction along the first reference surface S1 on the array surface 47 of the light-receiving elements 46, of which the set number is for each light-receiving pixel 48. This improves the reliability of the effect of ensuring resolution.

[0059] According to the first embodiment, SPADs serving as light receiving elements 46 are arranged in two-dimensional directions along the first reference plane S1 and the second reference plane S2. This makes it possible to ensure an appropriate dynamic range by making the light receiving elements 46 respond to the reflected beam RB having an intensity distribution, particularly in the direction along the second reference plane S2.

[0060] Second Embodiment As shown in FIGS. 12 and 13, the second embodiment is a modification of the first embodiment.

[0061] In the light receiving section 2041 of the second embodiment, an aperture unit 410 is arranged downstream of the cylindrical lens 43b and upstream of the bandpass element 422 in the light receiving optical system 2042 inside the housing 11. As a result, the optical opening 411 of the aperture unit 410 transmits the reflected beam RB, which has been optically affected by the elements 43a, 420, and 43b in the light receiving optical system 42, toward the bandpass element 422 and the light receiving unit 45.

[0062] A collimating element 2424 is added to the light receiving optical system 2042 of the second embodiment. The collimating element 2424 is arranged in the housing 11 after the aperture unit 410 and before the bandpass element 422. The collimating element 2424 is a collimating lens that collimates the reflected beam RB that has passed through the aperture unit 410 into a substantially parallel beam or a beam approximating the parallel beam, and then makes the reflected beam RB incident on the bandpass element 422.

[0063] The collimating element 2424 is formed mainly from a lens substrate such as synthetic resin or glass that is translucent in the near-infrared range. Therefore, the bandpass element 422 may be superimposed and joined to a subsequent bandpass element 422 that is mainly made of a filter substrate, as in the first embodiment. The collimating element 2424 may be covered with a filter film that serves as the bandpass element 422 and that is translucent in the near-infrared range but has substantially zero transmittance for other bands.

[0064] Here, particularly in the second embodiment, a plano-convex cylindrical collimating lens is selected for the collimating element 2424, with its generatrix direction aligned with the Y-axis direction and its positive power direction aligned with the X-axis direction. As a result, the collimating element 2424 applies different positive powers in the Y-axis direction and the X-axis direction to the reflected beam RB, which is elongated in the Y-axis direction. That is, the collimating element 2424 applies different positive powers on the first reference surface S1 and on the second reference surface S2 to the reflected beam RB, which is elongated along the first reference surface S1. As a result, the bandpass element 422 limits the transmission of the reflected beam RB, which has been optically affected by the collimating element 2424 in the light receiving optical system 2042, to the near-infrared region.

[0065] In this way, the collimating element 2424 of the light receiving optical system 2042 according to the second embodiment collimates the reflected beam RB that has passed through the aperture unit 410 and transmits it to the bandpass element 422. This makes it possible to prevent the reflected beam RB, which has an intensity distribution in the X-axis direction along the second reference plane S2, from being subject to transmission restrictions from the bandpass element 422 depending on the angle of incidence on the optical sensor 10. This makes it possible to increase the reliability of the effect of ensuring a dynamic range. Furthermore, the second embodiment can also achieve the same effects as the first embodiment.

[0066] (Third embodiment) As shown in FIGS. 14 to 16, the third embodiment is a modification of the first embodiment.

[0067] In the light-receiving unit 3045 of the third embodiment, a tilt axis XZA is defined that is orthogonal to the Y axis and tilts with respect to both the received light axis ROA (i.e., the Z axis) and the X axis at an acute angle on one side about the Y axis and an obtuse angle on the other side about the Y axis. Under this definition, the array surface 3047 of each light-receiving element 46 in the light-receiving unit 3045 is positioned so as to extend in the direction of the tilt axis XZA and in the Y axis direction. As a result, the array surface 3047 is tilted with respect to both the first reference plane S1 and the third reference plane S3. Here, in a cross section (see FIG. 15 ) that is orthogonal to the Y axis and includes the received light axis ROA, the array surface 3047 may be closer to the received light axis ROA on either side of the received light axis ROA in the X axis direction.

[0068] 16, the light receiving elements 46 are also arranged in the set direction of the tilt axis XZA and the Y-axis direction, which are two-dimensional directions along the first reference surface S1 and the second reference surface S2, on the inclined array surface 3047. At the same time, the light receiving pixels 48, each composed of a set number of light receiving elements 46, are also arranged in the Y-axis direction, which is a one-dimensional direction along the first reference surface S1, on the inclined array surface 3047. Furthermore, as shown in FIG. 15, the reflection direction of the retroreflected component RC of the reflected beam RB by the inclined array surface 47 is adjusted so that it not only deviates from the light receiving optical axis ROA due to the inclined arrangement, but also deviates from the optical opening 411 of the aperture unit 410.

[0069] As described above, in the light-receiving unit 3045 of the third embodiment, the array surface 3047 of the light-receiving elements 46 is inclined relative to the first reference plane S1. This allows the retroreflected component RC of the reflected beam RB by the light-receiving unit 3045 to be guided in a direction away from the received light optical axis ROA, thereby preventing the retroreflected component from generating ghost beams due to the ROA. Therefore, ensuring resolution and dynamic range is less likely to be hindered by ghost beams.

[0070] In the light-receiving unit 3045 of the third embodiment, the retroreflected component RC of the beam RB reflected by the array surface 3047 of the light-receiving elements 46 is guided so as to also miss the optical opening 411 in the aperture unit 410 due to the inclined arrangement of the array surface 3047. This makes it possible to prevent the reflected beam RB, which has an intensity distribution in the X-axis direction along the second reference plane S2, from being mixed in as a ghost beam by entering the optical opening 411 after being retroreflected by the light-receiving unit 3045 and being further reflected by the aperture unit 410. Therefore, ensuring the dynamic range in particular is less likely to be hindered by ghost beams.

[0071] Furthermore, the third embodiment can also achieve the same effects as the first embodiment. The third embodiment may be implemented in combination with the second embodiment.

[0072] (Fourth embodiment) As shown in FIGS. 17 and 18, the fourth embodiment is a modification of the first embodiment.

[0073] The light receiving unit 4041 of the fourth embodiment is provided with a module case 4412. The module case 4412 is formed from a light-blocking material, such as synthetic resin, metal, or ceramics. The module case 4412 has a box shape smaller than the light-blocking case 12 overall, and is disposed within the housing 11. The module case 4412 is constructed from a single component or a combination of multiple components. The module case 4412 houses and holds the light receiving unit 45 and the aperture unit 410 inside. As a result, the light receiving unit 45 is packaged together with the aperture unit 410 to form a light receiving module 4450.

[0074] The through-hole provided in the module case 4412 is entirely closed by the module cover 4413. As a result, the light receiving unit 45 and the aperture unit 410 are sealed in a mounted state within the module case 4412. The module cover 4413 is formed mainly from a base material, such as synthetic resin or glass, that is translucent in the near-infrared range. The module cover 4413 has a flat plate shape as a whole. The aperture unit 410 is superimposed and joined to the exit surface of the module cover 4413, which emits the reflected beam RB to the aperture unit 410. The entrance surface of the module cover 4413, onto which the reflected beam RB from the bandpass element 422 is incident, may be coated with an anti-reflection film that prevents reflection of the beam RB, etc.

[0075] The fourth embodiment can also achieve the same effects as the first embodiment. The fourth embodiment may be implemented in combination with at least one of the second and third embodiments.

[0076] Fifth Embodiment As shown in FIGS. 19 and 20, the fifth embodiment is a modification of the fourth embodiment.

[0077] The module case 5412 of the fifth embodiment accommodates and holds the light receiving optical system 42 inside, in addition to the aperture unit 410 and the light receiving unit 45. As a result, the light receiving optical system 42 is packaged together with the aperture unit 410 and the light receiving unit 45 to form a light receiving module 5450.

[0078] The through-hole provided in the module case 5412 is entirely blocked by the rotationally symmetric lens 43a at the forefront stage in the light-receiving optical system 42. As a result, the aperture unit 410, the light-receiving unit 45, and elements 420, 43b, and 422 at the rear side of the rotationally symmetric lens 43a in the light-receiving optical system 42 are sealed in a mounted state within the module case 5412.

[0079] The fifth embodiment can also achieve the same effects as the first embodiment. The fifth embodiment may be implemented in combination with at least one of the second and third embodiments.

[0080] (Other embodiments) Although multiple embodiments have been described above, the present disclosure should not be construed as being limited to those embodiments, and can be applied to various embodiments and combinations within the scope that does not deviate from the gist of the present disclosure.

[0081] In a modified example, the X-axis direction may be set to the vertical direction of the vehicle, and the Y-axis direction and the Z-axis direction may be set to the horizontal direction of the vehicle. In a modified example, the light receiving elements 46 may be mainly composed of, for example, photodiodes other than SPADs. In a modified example, the light receiving pixels 48, each composed of a set number of light receiving elements 46, may be arranged in a two-dimensional direction.

[0082] In the modified light-receiving optical system 42, 2042, the apodization element 420 may be disposed upstream of the rotationally symmetric lens 43a. In the modified apodization element 420, the light-shielding film that limits transmittance to substantially zero may be omitted from the outermost peripheral portion 421. In the modified light-receiving optical system 42, the bandpass element 422 may be disposed upstream of the rotationally symmetric lens 43a, between the rotationally symmetric lens 43a and the apodization element 420, or between the apodization element 420 and the cylindrical lens 43b. In the modified light-receiving optical system 42, the bandpass element 422 may be omitted. In the modified light-receiving optical system 42, the collimating element 2424 may be omitted from the light-receiving optical system 2042, as shown in FIG. 21 .

[0083] In the modified example, a rotationally asymmetric lens such as a toric lens may be selected for the light receiving lens 43 to be combined with the rotationally symmetric lens 43a, as long as the different positive powers and focal positions in the Y-axis direction and the X-axis direction described in the first embodiment are possible with this combination. In the modified example, a single lens or three or more lenses may be selected for the light receiving lens 43, as long as the different positive powers and focal positions in the Y-axis direction and the X-axis direction described in the first embodiment are possible.

[0084] In the modified example, a rotationally asymmetric lens such as a toric lens may be selected for the illumination lens 27 to be combined with the rotationally symmetric lens 27b, as long as the different positive powers in the Y-axis direction and the X-axis direction described in the first embodiment are possible with this combination. In the modified example, a single lens or three or more lenses may be selected for the illumination lens 27, as long as the different positive powers in the Y-axis direction and the X-axis direction described in the first embodiment are possible.

[0085] In a modified example, the scanning unit 31 may employ various driving methods, such as a mechanical oscillation type limited to scanning in the horizontal direction as described in the first embodiment, a mechanical oscillation type limited to scanning in the vertical direction, or a mechanical oscillation type in both the horizontal and vertical directions, etc. In a modified example, the scanning unit 31 may employ various scanning methods, such as a rotation type, a MEMS (Micro Electro Mechanical Systems) type, or a Lissajous type.

[0086] (Additional remarks) This specification discloses the following technical ideas and combinations thereof.

[0087] (Technical thought 1) An optical sensor that performs sensing by irradiating a linear irradiation beam (IB) toward a sensing area (SA) in the outside world and receiving a reflected beam (RB) from the sensing area in response to the irradiation beam on an optical axis (ROA), a light-receiving optical system (42, 2042) that applies different positive powers on a first reference surface (S1) and a second reference surface (S2) that are perpendicular to each other to the first reference surface and the second reference surface, to the reflected beam that is elongated along the first reference surface, and that attenuates the transmittance of the reflected beam as it moves away from the optical axis along the second reference surface; an aperture unit (410) that forms an optical aperture (411) along the first reference surface, the optical aperture being aligned with a focal point (PF2) on the second reference surface by the light receiving optical system and that transmits the reflected beam that has been optically affected by the light receiving optical system; An optical sensor comprising a light receiving unit (45, 3045) that receives the reflected beam that has passed through the optical aperture using a plurality of light receiving elements (46) that are aligned with the focal point (PF1) on the first reference surface by the light receiving optical system and are arranged in a two-dimensional direction along the first reference surface and the second reference surface.

[0088] (Technical thought 2) The light receiving optical system includes: An optical sensor described in technical idea 1, having an apodization element (420) that is aligned at a conjugate point with respect to the array surface (47, 3047) of the light receiving elements in the light receiving unit and that attenuates the transmittance of the reflected beam as it moves away from the optical axis along the second reference plane.

[0089] (Technical Thought 3) The aperture unit includes: The optical sensor described in Technical Idea 1 or 2 is positioned within the allowable distance along the optical axis from the focus (PF2) on the second reference plane by the light receiving optical system, with the size (Δa) of the optical aperture in the direction along the second reference plane being the allowable distance.

[0090] (Technical Thought 4) The light receiving optical system includes: The optical sensor according to any one of Technical Ideas 1 to 3, further comprising a bandpass element (422) that limits transmission of the reflected beam to a set band of the irradiated beam.

[0091] (Technical Thought 5) The light receiving optical system (2042) An optical sensor according to Technical Idea 4, having a collimating element (2424) that collimates the reflected beam that has passed through the aperture unit and transmits it to the bandpass element.

[0092] (Technical Thought 6) The light receiving unit is a plurality of light-receiving pixels (48) each including a set number of the light-receiving elements and serving as a unit for reading out a light-receiving signal; The array surface (47, 3047) of the light receiving elements in the light receiving unit is An optical sensor described in any one of technical ideas 1 to 5, which is positioned within the allowable distance along the optical axis from the focus (PF1) on the first reference plane by the light receiving optical system, with the size (Δp) of the light receiving pixel in the direction along the second reference plane being the allowable distance.

[0093] (Technical Thought 7) The single photon avalanche diode as the light receiving element is The optical sensor according to any one of Technical Ideas 1 to 6, which is arranged in a two-dimensional direction along the first reference surface and the second reference surface.

[0094] (Technical Thought 8) The array surface (3047) of the light receiving elements in the light receiving unit (3045) is The optical sensor according to any one of Technical Concepts 1 to 7, wherein the optical sensor is disposed so as to be inclined with respect to the first reference plane.

[0095] (Technical Thought 9) The optical sensor according to Technical Idea 8, wherein the retroreflected component (RC) of the reflected beam from the array surface (3047) of the light receiving elements in the light receiving unit is deflected from the optical aperture due to the inclined arrangement of the array surface.

[0096] (Technical Thought 10) The optical sensor according to any one of Technical Ideas 1 to 9, further comprising a scanning unit (31) that scans the irradiating beam toward the sensing area and reflects the reflected beam toward the light receiving optical system.

[0097] (Technical Thought 11) The optical sensor according to any one of Technical Ideas 1 to 10, wherein the light receiving unit is packaged together with the aperture unit to form a light receiving module (4450).

[0098] (Technical Thought 12) The optical sensor according to any one of Technical Ideas 1 to 10, wherein the light receiving optical system is packaged together with the light receiving unit and the aperture unit to form a light receiving module (5450).

[0099] (Technical Thought 13) The present invention is applied to the optical sensor according to any one of Technical Ideas 1 to 12, a light receiving module configured by packaging the light receiving optical system together with the light receiving unit and the aperture unit; [Explanation of symbols]

[0100] 10: optical sensor, 31: scanning unit, 42, 2042: light receiving optical system, 45, 3045: light receiving unit, 46: light receiving element, 47, 3047: array surface, 48: light receiving pixel, 410: aperture unit, 411: optical aperture, 420: apodization element, 422: band pass element, 2424: collimating element, 4450, 5450: light receiving module, IB: irradiation beam, PF1, PF2: focus, RB: reflected beam, RC: retroreflected component, ROA: receiving optical axis, S1: first reference plane, S2: second reference plane, SA: sensing area, Δa: size, Δp: size

Claims

1. An optical sensor that performs sensing by irradiating a linear irradiation beam (IB) toward a sensing area (SA) in the outside world and receiving a reflected beam (RB) from the sensing area in response to the irradiation beam on an optical axis (ROA), a light-receiving optical system (42, 2042) that applies different positive powers on a first reference surface (S1) and a second reference surface (S2) that are orthogonal to each other to the first reference surface and the second reference surface, to the reflected beam that is elongated along the first reference surface, and that attenuates the transmittance of the reflected beam as it moves away from the optical axis along the second reference surface; an aperture unit (410) that forms an optical aperture (411) along the first reference surface, the optical aperture being aligned with a focal point (PF2) on the second reference surface by the light receiving optical system and that transmits the reflected beam that has been optically affected by the light receiving optical system; An optical sensor comprising: a light receiving unit (45, 3045) that receives the reflected beam that has passed through the optical aperture using a plurality of light receiving elements (46) that are aligned with a focal point (PF1) on the first reference surface by the light receiving optical system and arranged in a two-dimensional direction along the first reference surface and the second reference surface.

2. The light receiving optical system includes: The optical sensor of claim 1, further comprising an apodization element (420) aligned at a conjugate point with respect to the array surface (47, 3047) of the light receiving elements in the light receiving unit, and attenuating the transmittance of the reflected beam as it moves away from the optical axis along the second reference plane.

3. The aperture unit includes:

3. The optical sensor according to claim 1, wherein the size (Δa) of the optical aperture in a direction along the second reference plane is defined as an allowable distance, and the optical sensor is positioned within the allowable distance along the optical axis from a focus (PF2) on the second reference plane by the light receiving optical system.

4. The light receiving optical system includes:

3. An optical sensor according to claim 1 or 2, comprising a bandpass element (422) for limiting transmission of the reflected beam to a set band of the illumination beam.

5. The light receiving optical system (2042) 5. The optical sensor of claim 4, further comprising a collimating element (2424) for collimating the reflected beam transmitted through the aperture unit and transmitting it to the bandpass element.

6. The light receiving unit is a plurality of light-receiving pixels (48) each including a set number of the light-receiving elements and serving as a unit for reading out a light-receiving signal; The array surface (47, 3047) of the light receiving elements in the light receiving unit is 3. The optical sensor according to claim 1, wherein the size (Δp) of the light-receiving pixel in a direction along the second reference plane is defined as an allowable distance, and the sensor is positioned within the allowable distance along the optical axis from a focus (PF1) on the first reference plane by the light-receiving optical system.

7. The single photon avalanche diode as the light receiving element is The optical sensor according to claim 1 or 2, wherein the optical sensor is arranged in a two-dimensional direction along the first reference surface and the second reference surface.

8. The array surface (3047) of the light receiving elements in the light receiving unit (3045) is The optical sensor according to claim 1 or 2, wherein the optical sensor is disposed at an angle with respect to the first reference plane.

9. 9. The optical sensor according to claim 8, wherein a retroreflection component (RC) of the reflected beam from an array surface (3047) of the light receiving elements in the light receiving unit is deviated from the optical aperture due to an inclined arrangement of the array surface.

10. 3. The optical sensor according to claim 1, further comprising a scanning unit (31) that scans the irradiating beam toward the sensing area and reflects the reflected beam toward the light receiving optical system.

11. The optical sensor according to claim 1 or 2, wherein the light receiving unit is packaged together with the aperture unit to form a light receiving module (4450).

12. The optical sensor according to claim 1 or 2, wherein the light receiving optical system is packaged together with the light receiving unit and the aperture unit to form a light receiving module (5450).

13. The optical sensor according to claim 1 or 2, a light receiving module configured by packaging the light receiving optical system together with the light receiving unit and the aperture unit;

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