Optical sensor

Abstract

An optical sensor is provided with: an optical unit (2) including a light projecting unit (20) that projects a projected beam (PB) within a housing unit (1) and a light receiving unit (40) that receives a reflected beam (RB) within the housing unit (1); a scanning unit (3) that scans a projected beam (PB) from the light projecting unit (20) toward the outside within the housing unit (1) and reflects a reflected beam (RB) from the outside toward the light receiving unit (40) within the housing unit (1); and a control unit for controlling the optical unit (2) and the scanning unit (3), the control unit (5) being configured so as to execute monitoring control for monitoring the optical characteristics of the optical unit (2) in response to the scanning unit (3) forming each optical path (PL, RL) between the reflection section (190) and the optical unit (2). The reflection part is arranged outside the coverage area of each optical path (PL, RL) under the detection control in the housing unit (1).

Description

[0001] Cross-references between related applications

[0002] This application is based on patent application No. 2023-6151 filed in Japan on January 18, 2023, and the contents of the basic application are incorporated herein by reference in their entirety. Technical Field

[0003] The present disclosure relates to optical sensors. Background Art

[0004] Optical sensors are widely known that receive a reflected beam from a light projecting unit via a light receiving unit. Patent Document 1, one such optical sensor, describes a device that performs self-diagnosis of the operating conditions of the light projecting unit and light receiving unit based on the reflected beam, while the light projecting unit's destination is changed from the outside to within a housing via a scanning unit.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2002-31685 Summary of the Invention

[0008] However, in the optical sensor disclosed in Patent Document 1, the optical path of the reflected beam during distance detection is separated from the optical path of the projected light beam scanned by the scanning unit by a partition wall, which hinders overall miniaturization. Furthermore, in the optical sensor disclosed in Patent Document 1, the projected light beam during self-diagnosis enters the optical path of the reflected beam through the aperture in the partition wall. When reflected by the inner surface of the incident window within the housing, the projected light beam may leak from the incident window to the outside world unnecessarily.

[0009] An object of the present disclosure is to provide a compact optical sensor that suppresses unnecessary beam leakage.

[0010] Hereinafter, technical means of the present disclosure for solving the problems will be described.

[0011] One embodiment of the present disclosure is an optical sensor that receives a reflected beam reflected from a projected light beam. The optical sensor includes: a housing unit that separates the outside world from the inside; an optical unit that includes a light projector and a light receiver, wherein the light projector projects the projected light beam within the housing unit and the light receiver receives the reflected beam within the housing unit; a scanning unit that scans the projected light beam from the light projector toward the outside world within the housing unit and reflects the reflected beam from the outside world toward the light receiver within the housing unit; and a control unit that controls the optical unit and the scanning unit. The housing unit includes a reflecting unit having a reflection characteristic for the projected light beam. The control unit is configured to execute detection control and monitoring control. The detection control detects the outside world in response to the scanning unit forming optical paths between the optical unit and the outside world in which coverage areas overlap with each other using the projected light beam and the reflected beam within the housing unit. The monitoring control monitors the optical characteristics of the optical unit in response to the scanning unit forming optical paths between the reflecting unit and the optical unit. The reflecting unit is arranged within the housing unit outside the coverage areas of the optical paths under detection control.

[0012] According to one embodiment of the present disclosure, during detection control for detecting the outside world, the scanning unit forms optical paths between the optical unit and the outside world, each with overlapping coverage areas of the projected light beam and the reflected light beam within the housing unit that separates the outside world from the interior. This allows the optical unit within the housing unit to position the light projecting portion that projects the projected light beam and the light receiving portion that receives the reflected light beam as close together as possible, thereby minimizing the overall size of the optical sensor.

[0013] Furthermore, according to one embodiment of the present disclosure, during monitoring control for monitoring the optical characteristics of the optical unit, the scanning unit forms optical paths between a reflective portion of the housing unit and the optical unit. The reflective portion is disposed within the housing unit outside the coverage area of ​​the optical paths under detection control and is endowed with reflective characteristics. This allows the projected light beam under monitoring control to be separated from the optical path directed toward the outside under detection control and to remain within the housing unit, thereby suppressing unnecessary leakage of the projected light beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram showing the overall structure of the optical sensor according to the first embodiment in cross section.

[0015] Figure 2 It is a schematic diagram showing a longitudinal cross-section of the entire structure of the optical sensor according to the first embodiment.

[0016] Figure 3 It is a schematic diagram showing the light projecting unit according to the first embodiment.

[0017] Figure 4It is a schematic diagram showing the light receiving section of the first embodiment.

[0018] Figure 5 It is a perspective view showing the detailed structure of the optical sensor according to the first embodiment.

[0019] Figure 6 This is a schematic diagram showing the monitoring control of the optical sensor according to the first embodiment in a cross section.

[0020] Figure 7 It is a schematic diagram for explaining the detailed functions of the optical sensor according to the first embodiment.

[0021] Figure 8 This is a schematic diagram showing an enlarged detailed structure of the optical sensor according to the second embodiment.

[0022] Figure 9 It is a schematic diagram for explaining the detailed functions of the optical sensor according to the second embodiment. DETAILED DESCRIPTION

[0023] Hereinafter, multiple embodiments of the present disclosure will be described based on the accompanying drawings. In addition, the same symbols are given to corresponding constituent elements in each embodiment, so repeated descriptions are sometimes omitted. In addition, when only a part of the structure is described in each embodiment, the structure of other embodiments described above can be applied to the other parts of the structure. Furthermore, not only the combination of structures explicitly described in the description of each embodiment, but also the structures of multiple embodiments can be partially combined with each other even if not explicitly described, as long as the combination does not particularly cause obstacles.

[0024] (First embodiment)

[0025] like Figure 1 、 2 As shown, the optical sensor 100 of the first embodiment of the present disclosure is a LiDAR (Light Detection and Ranging / Laser Imaging Detection and Ranging, i.e., a laser detection and ranging system) configured on a mobile object for optically detecting the outside world. The mobile object to which the optical sensor 100 is configured is a vehicle such as a car that can be driven by at least one of manual driving, automatic driving, and remote driving. In addition, in the following description, unless otherwise specified, the directions shown as front, rear, up, down, left, and right are defined with respect to the vehicle on a horizontal plane. In addition, in the following description, the horizontal direction and the vertical direction refer to the parallel direction and the perpendicular direction relative to the horizontal plane in the vehicle on the horizontal plane, respectively.

[0026] The optical sensor 100 is positioned, for example, at at least one location on the vehicle, such as the front, left and right sides, rear, or roof. The optical sensor 100 scans a projected light beam PB across a detection area DA corresponding to the location in the vehicle. The optical sensor 100 detects the return light from the projected light beam PB reflected by an object in the detection area DA as a reflected beam RB. The projected light beam PB, which becomes the reflected beam RB, selects light in the near-infrared region, which is difficult for humans to visually perceive.

[0027] The optical sensor 100 detects external targets within the detection area DA by receiving a reflected beam RB that is reflected from the projected light beam PB. Detection of such external targets refers to one or more detections, including at least the distance, such as the distance from the optical sensor 100 to the target, the direction in which the target is located, and the intensity of the reflection beam RB from the target. Representative targets for detection in the optical sensor 100 used in a vehicle include, for example, at least one of moving objects such as pedestrians, cyclists, non-human animals, and other vehicles. Representative targets for detection in the optical sensor 100 used in a vehicle include, for example, at least one of stationary objects such as guardrails, road signs, structures beside the road, and fallen objects on the road.

[0028] In the optical sensor 100, a three-dimensional coordinate system is defined by the mutually orthogonal X-axis, Y-axis, and Z-axis. Specifically, in the three-dimensional coordinate system of the optical sensor 100, the Y-axis, serving as the reference direction, is defined as being in the vertical direction of the vehicle, while the X-axis and Z-axis directions are defined as being in different horizontal directions of the vehicle. Therefore, for a vehicle on a horizontal surface, the XY and YZ planes of the three-dimensional coordinate system lie along a vertical plane perpendicular to the horizontal plane, with the XZ plane also lying along the horizontal plane.

[0029] The optical sensor 100 includes a housing unit 1, an optical unit 2, a scanning unit 3, and a control unit 5. The housing unit 1, which separates the outside from the inside, has a housing body 12 and a light-transmitting window 16 for forming a housing chamber 10 therein. The housing chamber 10 houses the other units 2, 3, and 5 of the optical sensor 100.

[0030] The housing body 12 is primarily composed of multiple base materials such as metal or synthetic resin, and is formed into a box shape surrounding the housing chamber 10. The housing body 12 has an optical opening 13 formed therein, which opens in the X-axis direction. At least one of the outer and inner surfaces of the housing body 12 is provided with light-shielding properties by setting low transmittance, low reflectance, and high absorptivity as optical properties for light in the near-infrared and visible regions.

[0031] Light-transmitting window 16 is primarily constructed from a base material such as resin or glass, and is formed into a flat plate facing storage chamber 10. Light-transmitting window 16 is surrounded and retained by housing body 12 from the outside, thereby sealing optical opening 13. Light-transmitting window 16 is given light-transmitting properties by designing high transmittance, low absorptivity, and low reflectivity as optical properties for light in the near-infrared region. As described above, light-transmitting window 16 exerts its light-transmitting properties between the outside world and the interior of housing unit 1, allowing projected light beam PB to pass from storage chamber 10 to detection area DA, and allowing reflected light beam RB to pass from detection area DA to storage chamber 10.

[0032] The optical unit 2 includes a light projecting unit 20 and a light receiving unit 40. Hereinafter, for easier understanding of the description, the light projecting unit 20 will be described first, and the light receiving unit 40 will be described after the description of the scanning unit 3.

[0033] like Figure 1 As shown, the light projection unit 20 includes a light projection light source module 22 and a light projection lens module 26. Figure 3 As shown, the light source module 22 is constructed by mounting a plurality of light sources 24 in an array on a substrate held by the housing unit 1. In particular, each light source 24 of this embodiment is a laser diode arranged in a single row in a manner separated from each other along the Y-axis direction. Each light source 24 generates a pulsed individual beam PBi (see below) by generating a laser beam that becomes a part of the light beam PB according to a control signal from the control unit 5. Figure 7 Each light source 24 can be an edge emitter laser or a vertical cavity surface emitting laser (VCSEL).

[0034] The light source module 22 has a light source window 25 formed on one side of the substrate. The light source window 25 is approximately defined as a rectangular outline with the long side along the Y-axis direction and the short side along the X-axis direction. The light source window 25 is formed as a collection of laser oscillation openings in each light source 24. The individual beams PBi (see below) projected from the laser oscillation openings of each light source 24 are Figure 7 ) At least in the external detection area DA, the light beam PB is projected from the light source window 25 as a linear beam shaped into a long side along the vertical direction.

[0035] like Figure 1As shown, the projection lens module 26 is constructed with at least one projection lens 260 held by the housing unit 1 via a lens barrel 261. The translucent projection lens 260 is primarily made of a base material such as resin or glass, and is formed into a lens shape corresponding to the optical function it performs. The projection lens 260 performs at least one optical function, such as focusing, collimating, and shaping, on the projection beam PB from the projection light source module 22. The projection lens 260 is positioned within a light-shielding lens barrel 261, such as one formed of metal or resin.

[0036] The light projection lens module 26 having such a structure is aligned with the light projection light source module 22 in the Z-axis direction. Figure 1 、 2 As shown, a projection optical axis POA is formed in the housing chamber 10 within the housing unit 1. Therefore, in the housing chamber 10, the projection beam PB projected from the projection light source module 22 is projected toward the scanner unit 3 side, which is the external side, along the projection optical axis POA by the optical action of the projection lens module 26.

[0037] The scanning unit 3 includes a scanning mirror 32 and a scanning motor 36. Within the housing chamber 10 within the housing unit 1, the scanning mirror 32 is configured to be offset from the optical unit 2 in the Z-axis direction and from the light-transmitting window 16 in the X-axis direction. The scanning mirror 32 is formed in the shape of a plate with a reflective film deposited on a single-sided mirror surface 33 serving as a substrate. The scanning mirror 32 is supported by the housing unit 1 so as to be rotatable about a rotation centerline along the Y-axis. The scanning mirror 32 can swing within a limited drive range using mechanical or electrical stops.

[0038] In the storage chamber 10, a scanning motor 36 is arranged around the scanning mirror 32. The scanning motor 36 is, for example, a voice coil motor, a brushed DC motor, or a stepping motor. The output shaft of the scanning motor 36 is directly coupled to the scanning mirror 32 or indirectly coupled to the scanning mirror 32 via a drive mechanism such as a speed reducer. The scanning motor 36 is held by the housing unit 1 in such a manner that it can drive the scanning mirror 32 to rotate together with the output shaft. The scanning motor 36 rotationally drives (i.e., swings) the scanning mirror 32 within a drive range based on a control signal from the control unit 5.

[0039] Therefore, within the storage chamber 10, the scanning mirror 32 reflects the projected light beam PB, projected from the light projection lens module 26 of the light projection unit 20, toward the light transmission window 16 via the mirror surface 33 corresponding to the rotation angle of the scanning motor 36. Thus, the scanning mirror 32 causes the projected light beam PB, which is about to pass through the light transmission window 16, to scan the detection area DA in the outside world. At this time, the scanning of the projected light beam PB across the detection area DA by the rotational drive of the scanning mirror 32 is essentially limited to scanning in the horizontal direction in this embodiment.

[0040] At the same time, within the storage chamber 10, the scanning mirror 32 uses the mirror surface 33 corresponding to the rotation angle of the scanning motor 36 to reflect the reflected beam RB, which enters the detection area DA from the outside through the light-transmitting window 16, toward the light receiving unit 40. At this time, the speeds of the projected light beam PB and the reflected beam RB are sufficiently higher than the rotational speed of the scanning mirror 32. As a result, the reflected beam RB is reflected from the scanning mirror 32, which can simulate the angle with respect to the projected light beam PB at substantially the same rotation angle, and is thereby guided toward the light receiving unit 40 in a direction counter to the projected light beam PB.

[0041] The light receiving unit 40 is arranged to be offset in the Y-axis direction relative to the light projecting unit 20, and thus together with the light projecting unit 20, constitutes the optical unit 2 offset from the scanning mirror 32 in the Z-axis direction. Figure 1 As shown, the light receiving unit 40 includes a light receiving lens module 42 and a light receiving detection module 45. The light receiving lens module 42 is constructed such that at least one light receiving lens 420 is held by the housing unit 1 via a lens barrel 421. The light transmitting light receiving lens 420 is primarily made of a base material such as resin or glass and has a lens shape corresponding to the optical function it performs. The light receiving lens 420 performs an optical function to form an image of the reflected beam RB from the scanning mirror 32 toward the light receiving detection module 45. The light receiving lens 420 is positioned within a light shielding lens barrel 421 formed, for example, of metal or resin.

[0042] like Figure 1 、 2 As shown, the light-receiving lens module 42 and the light-receiving detection module 45 are aligned with an offset in the Z-axis direction to form a light-receiving optical axis ROA in the housing chamber 10 within the housing unit 1. The light-receiving optical axis ROA of the light-receiving lens module 42 is offset in the Y-axis direction relative to the light-projecting optical axis POA of the light-projecting lens module 26. As a result, in the housing chamber 10, the reflected beam RB, which is reflected from the mirror surface 33 of the scanning mirror 32 in a manner offset from the light-projecting beam PB in the Y-axis direction, is guided along the light-receiving optical axis ROA by the optical action of the light-receiving lens module 42 and is received by the light-receiving detection module 45.

[0043] In such a storage chamber 10, the footprint PF of the optical path PL formed by the projected light beam PB and the footprint RF of the optical path RL formed by the reflected light beam RB form an overlapping area SA that partially overlaps in the Y-axis direction within the driving range of the scanning mirror 32. Specifically, the footprints PF and RF of the projected light beam PB and the reflected light beam RB are designed to partially overlap on at least one of the surfaces of the light-transmitting window 16 on the storage chamber 10 side and the outside side. Thus, the light-transmitting window 16 is located within the footprints PF and RF of each optical path PL and RL in the storage chamber 10, and exhibits light transmission properties between the outside world and the storage chamber 10 for each beam PB and RB. The footprints PF and RF described above respectively refer to spatial regions that can be formed by the optical paths PL and RL, which serve as the trajectories of each beam PB and RB under the detection control Cd described later, throughout the driving range of the scanning mirror 32.

[0044] like Figure 4 As shown, the light-receiving detection module 45 is constructed by installing a plurality of light-receiving pixels 46 in an array on a substrate held by the housing unit 1. Each light-receiving pixel 46 is arranged at least along the Y-axis direction. The light-receiving detection module 45 forms a light-receiving surface 450 on a single side of the substrate, and the light-receiving surface 450 has a rectangular outline with a long side along the Y-axis direction and a short side along the X-axis direction. The light-receiving surface 450 is constituted as an aggregate of the incident surfaces in each light-receiving pixel 46. Here, each light-receiving pixel 46 is also formed by, for example, a single photon avalanche diode (Single Photon Avalanche Diode) as a plurality of light-receiving elements 460. Each of such light-receiving pixels 46 receives the reflected beam RB incident from the light-receiving lens module 42 to the light-receiving surface 450 as a linear beam extending along the Y-axis direction.

[0045] like Figure 1 As shown, the light-receiving detection module 45 includes an output circuit 47. The output circuit 47 performs sampling processing every control cycle according to the control signal from the control unit 5, synchronized with the projection cycle of the projection beam PB from the projection light source module 22 and corresponding to the rotation angle of the scanning mirror 32, within the detection frame of each scanning line. At this time, the output circuit 47 synthesizes the response outputs from the light-receiving elements 460 of each light-receiving pixel 46 every control cycle to generate a detection signal. The detection signal generated in this way is output from the output circuit 47 to the control unit 5 for each scanning line.

[0046] Figure 2The control unit 5 shown is constructed mainly from at least one of a processor and a computer including a memory. The control unit 5 is connected to the light projection light source module 22, the scanning motor 36, and the light receiving detection module 45. The control unit 5 controls the light projection light source module 22 in the optical unit 2 to generate a light projection beam PB during each light projection cycle. At the same time, the control unit 5 controls the scanning motor 36 to control the scanning and reflection of the scanning mirror 32 in synchronization with the light projection cycle of the light projection light source module 22. Furthermore, the control unit 5 processes the detection signal output from the light receiving detection module 45 in the optical unit 2 in accordance with the light projection cycle of the light projection light source module 22 and the scanning and reflection of the scanning mirror 32.

[0047] Here, if Figure 1 、 2 As shown, in detection control Cd for detecting an object target within detection area DA in the outside world, control unit 5 processes detection signals from light-receiving detection module 45 to generate three-dimensional point cloud data as object detection data. Therefore, detection control Cd is executed in accordance with the overlapping optical paths PL and RL of the coverage areas PF and RF of the beams PB and RB formed by scanning unit 3 between optical unit 2 and the outside world within housing unit 1.

[0048] (Detailed structure, detailed function)

[0049] Next, the detailed structure and detailed functions of the optical sensor 100 will be described. Figure 1 、 2 As shown in Figures 5 and 6 , the housing unit 1 further includes a frame component 18 and a reflective component 19 .

[0050] Frame member 18 is primarily composed of a base material such as metal or synthetic resin, and is formed into a partition wall that divides chamber 10 into two halves in the X-axis direction. Frame member 18 is surrounded and retained by housing body 12 from its outer periphery, with one surface thereof facing light-transmitting window 16 in the X-axis direction. Frame member 18 imparts light-shielding properties by designing its two surfaces with low transmittance, low reflectance, and high absorptivity as optical properties for light in the near-infrared and visible regions.

[0051] In the housing chamber 10 within the housing unit 1, the frame member 18 holds the components 20 and 40 of the optical unit 2 and the scan motor 36 on the side opposite the light-transmitting window 16 in the X-axis direction. Furthermore, within the housing chamber 10, the frame member 18 peripherally surrounds the coverage areas PF and RF of the optical paths PL and RL formed by the respective beams PB and RB, using a scan opening 180 extending through both surfaces.

[0052] On one side of the scanning opening 180 in the Z-axis direction, the frame member 18 is curved along both the YZ plane and the XY plane. This allows a light shielding portion 181, particularly around the reflector 190 (described later), to have light-shielding properties for the respective beams PB and RB. Consequently, within the storage chamber 10, light shielding portion 181 is disposed in a region opposite to the optical unit 2 in the Z-axis direction, across the scanning unit 3, and outside the coverage areas PF and RF of the respective optical paths PL and RL under the detection control Cd.

[0053] The reflective member 19 is primarily formed of a base material such as metal or synthetic resin, and is formed into a curved plate shape. The reflective member 19 is retained along the YZ plane on the side of the light-transmitting window 16 within the light-shielding portion 181 of the frame member 18. Thus, within the storage chamber 10, the reflective member 19 is positioned outside the coverage areas PF and RF of the respective optical paths PL and RL under the detection control Cd, and in an area opposite the optical unit 2 in the Z-axis direction across the scanning unit 3. Furthermore, within the storage chamber 10, the light-transmitting window 16 is provided within the coverage areas PF and RF of the respective optical paths PL and RL under the detection control Cd, avoiding the area where the reflective member 19 is positioned.

[0054] The reflective component 19 is formed by a curved portion extending along the YZ plane and the XY plane to form a reflective portion 190, which extends along the light shielding portion 181 around the sides of each unit 3 and 2 in the Z-axis direction. The reflective portion 190 is constructed by the surface of the curved portion facing the sides of each unit 3 and 2 along the YZ plane in the Z-axis direction, forming a reflective surface 191 with a long side in the Y-axis direction, which is the reference direction. By setting low transmittance, low absorptivity, and high diffuse reflectivity as optical properties for light in the near-infrared region, the reflective surface 191 is given reflective properties. Here, the diffuse reflectivity of the reflective surface 191 particularly represents the optical property of diffusely reflecting (i.e., irregularly reflecting) light (here, the projection beam PB) due to the unevenness of the surface of the reflective portion 190. Therefore, the reflective surface 191 is formed as a uniform diffuse reflection surface, for example.

[0055] The control unit 5 is configured to correspond to such a detailed structure, for example, when the optical sensor 100 is activated. Figure 1 、 2 The detection control Cd is not implemented during the period, such as Figure 6 In this manner, monitoring control Cm, which is a detailed function different from detection control Cd, is executed. Here, in monitoring control Cm, optical characteristics related to the monitored object, such as changes in the projected light intensity of the projected light beam PB or changes in the received light intensity of the reflected beam RB due to abnormality, failure, or aging, are monitored. The monitored object is at least one of the components 20 and 40 in the optical sensor 100.

[0056] Therefore, in response to the scanning unit 3 forming the optical paths PL and RL between the reflecting unit 190 and the optical unit 2 and executing the monitoring control Cm, the reflecting unit 190 is located outside the coverage areas PF and RF of the optical paths PL and RL under the detection control Cd in the storage chamber 10 within the housing unit 1. At this time, a portion of the beam component of the reflected beam RB generated by the diffuse reflection of the projected light beam PB by the reflecting surface 191 of the reflecting unit 190 reaches the light receiving surface 450 of the light receiving detection module 45, thereby forming a light path between the reflecting unit 190 and the optical unit 2. Figure 6 Thus, optical paths PL and RL are formed. Consequently, the beam component reaching light-receiving surface 450 as reflected beam RB is received by light-receiving detection module 45 at a set intensity lower than that of the original projected beam PB, within a range capable of monitoring the optical characteristics of the object. Furthermore, with respect to reflected beam RB generated by diffuse reflection from reflective surface 191 of reflective portion 190, the beam component is suppressed from reaching light-transmitting window 16, and even if such beam component does reach light, the intensity of the beam component leaking to the outside is also suppressed.

[0057] As described above, in the monitoring control Cm, the control unit 5 generates characteristic data representing the optical characteristics of the monitored object based on the detection signal obtained by receiving the reflected beam RB reflected by the reflecting portion 190 having substantially constant reflection characteristics with respect to the projected light beam PB on the reflecting surface 191. Figure 7 As shown, the aggregate beam of the individual beams PBi partially overlapping in the Y-axis direction in the arrangement region of the reflector 190 is reflected as a projection beam PB by the reflective surface 191 that is long in the Y-axis direction.

[0058] (Effect)

[0059] The following describes the effects of the first embodiment described so far.

[0060] According to the first embodiment, during detection control Cd for detecting the outside world, the scanning unit 3 forms optical paths PL and RL between the optical unit 2 and the outside world, with overlapping coverage areas PF and RF of the projected light beam PB and reflected light beam RB within the housing unit 1, which separates the outside world from the interior. This allows the light projector 20, which projects the projected light beam PB, and the light receiver 40, which receives the reflected light beam RB, to be positioned as close as possible within the optical unit 2 within the housing unit 1, thereby minimizing the overall size of the optical sensor 100.

[0061] Furthermore, according to the first embodiment, during monitoring control Cm, which monitors the optical characteristics of the optical unit 2, the scanning unit 3 forms optical paths PL and RL between the reflector 190 of the housing unit 1 and the optical unit 2. The reflector 190 is positioned within the housing unit 1 outside the coverage areas PF and RF of the optical paths PL and RL under the detection control Cd and is endowed with reflective characteristics. This allows the projected light beam PB under monitoring control Cm to deviate from the optical paths PL and RL directed toward the outside under the detection control Cd and remain within the housing unit 1, thereby suppressing unnecessary leakage of the projected light beam PB.

[0062] The reflector 190 of the first embodiment imparts reflective properties to the reflective surface 191 that diffusely reflects the projected light beam PB. This allows the light receiving unit 40 to receive the reflected beam RB, even when reflected by the reflector 190, which is closer to the light receiving unit 40 than the outside world, at a reduced intensity compared to the projected light beam PB. This prevents the accuracy of optical characteristic monitoring in the monitoring control Cm from being reduced due to saturation of the intensity of the reflected beam RB received by the light receiving unit 40.

[0063] The light projecting unit 20 of the first embodiment projects a linear beam PB, the longer side of which is at least along the Y-axis, which serves as a reference direction, to the outside world. Therefore, the reflective unit 190 of the first embodiment imparts reflective properties to a reflective surface 191 that is elongated along the Y-axis, along which the light projecting beam PB extends. This allows the reflective unit 190 to be formed to the minimum size necessary to match the shape of the light projecting beam PB. This contributes to the miniaturization of the optical sensor 100.

[0064] The reflector 190 of the first embodiment is arranged in a region opposite to the optical unit 2, with the scanner unit 3 interposed therebetween, within the frame member 18 that holds the optical unit 2 and the scanner unit 3 in the housing unit 1. This allows the reflector 190 to be arranged as close to the optical unit 2 as possible by effectively utilizing the frame member 18 that constitutes the housing unit 1, thereby contributing to miniaturization of the optical sensor 100.

[0065] The light shielding portion 181 of the housing unit 1 of the first embodiment has light-shielding properties around the reflective portion 190 outside the coverage areas PF and RF of the respective optical paths PL and RL under the detection control Cd within the housing unit 1. Thus, during the detection control Cd, even if stray light from at least one of the beams PB and RB is emitted outside the respective optical paths PL and RL under the detection control Cd due to scattering, the light shielding portion 181 can suppress stray light from reaching the reflective portion 190. Consequently, it is possible to suppress beam leakage to the outside world caused by unnecessary reflection at the reflective portion 190 and reduce the accuracy of external detection.

[0066] In the housing unit 1 of the first embodiment, the light-transmitting window 16 of the housing unit 1 is disposed within the coverage areas PF and RF of the respective optical paths PL and RL under detection control Cd, avoiding the area where the reflector 190 is located. This light-transmitting window 16 of the housing unit 1 is configured to transmit light to the outside world with respect to the two beams PB and RB. Consequently, under monitoring control Cm, the reflected beam RB, which is reflected by the reflector 190 located outside the coverage areas PF and RF of the respective optical paths PL and RL under detection control Cd, can be prevented from leaking from the light-transmitting window 16 within these coverage areas PF and RF to the outside world.

[0067] At the same time, in the first embodiment, the beams PB and RB that pass through the light-transmitting window 16 within the coverage areas PF and RF under detection control Cd can be prevented from reaching the reflecting portion 190 outside of these coverage areas PF and RF. Therefore, beam leakage to the outside world caused by unnecessary reflection in the reflecting portion 190 and a reduction in the accuracy of external detection can be suppressed. Furthermore, according to the first embodiment, the light-transmitting window 16 that transmits the beams PB and RB within the coverage areas PF and RF under detection control Cd can suppress the arrival of the reflected beam RB due to diffuse reflection from the reflecting portion 190 outside the coverage areas PF and RF, and even if such reflection does occur, the intensity of the beam component that leaks to the outside world can be suppressed. Therefore, beam leakage to the outside world caused by diffuse reflection can be suppressed.

[0068] (Second embodiment)

[0069] like Figure 8 As shown, the second embodiment is a modified example of the first embodiment. The reflective component 2019 of the second embodiment has a plurality of reflective portions 2190 in the form of tabs, which are arranged separately from each other along the Y-axis direction, which serves as a reference direction. Each reflective portion 2190 is configured with an individual reflective surface 2191 using an inclined surface, and the inclined surface is oriented toward the side opposite to the light-transmitting window 16 in the X-axis direction along an acute angle α relative to the YZ plane and the XY plane. As in the first embodiment, low transmittance, low absorptivity, and high diffuse reflectance are set as the optical properties for light in the near-infrared region, thereby imparting reflective properties to the individual reflective surfaces 2191 of each reflective portion 2190.

[0070] According to such detailed configuration, in the monitoring control Cm of the second embodiment, as shown in FIG. Figure 9As shown, each reflector 2190 reflects the corresponding individual beam PBi from the corresponding projector light source 24 along its separated reflective surfaces 2191, each of which imparts reflective characteristics to the corresponding individual beam PBi. Adjacent individual beams PBi within the arrangement region of each reflector 2190 are separated and diffusely reflected by the separated reflective surfaces 2191, which avoid overlapping portions in the Y-axis direction. Therefore, in the monitoring control unit Cm that receives the separated reflected beams RB corresponding to the individual beams PBi, the control unit 5 generates characteristic data representing the optical characteristics of each projector light source 24 being monitored.

[0071] In the second embodiment described above, similar to the first embodiment, the light projecting unit 20 projects a linear beam PB, at least with its long side along the Y-axis, to the outside world by combining individual beams PBi from a plurality of light projecting sources 24 spaced apart and arranged along the Y-axis, serving as a reference direction. Therefore, in the second embodiment, each of the plurality of reflectors 2190 spaced apart and arranged along the Y-axis is assigned a reflection characteristic specific to the individual beams PBi from the corresponding light projecting source 24. Thus, in the monitoring control Cm, the reflected beam RB from the reflector 2190 is received for each individual beam PBi from each light projecting source 24 as a light projecting beam PB, enabling individual monitoring of the optical characteristics of each light projecting source 24. Consequently, the accuracy of monitoring the optical characteristics of the light projecting unit 20 can be particularly improved.

[0072] Here, in the second embodiment, the light projecting unit 20 also projects a linear beam PB with a long side along the Y-axis direction by gathering individual beams PBi that overlap in the Y-axis direction within the arrangement region of the reflectors 2190. Thus, in order to individually monitor the optical characteristics of each light source 24 using the monitoring control Cm, the plurality of reflectors 2190 can be arranged as close to each other as possible, thereby miniaturizing the optical sensor 100. The plurality of reflectors 2190 reflect the reflected beam RB for each individual beam PBi from each light source 24 as the light projecting beam PB.

[0073] (Other embodiments)

[0074] Although a plurality of embodiments have been described above, the present disclosure is not limited to these embodiments and can be applied to various embodiments and combinations within the scope not departing from the gist of the present disclosure.

[0075] In a modified example, a Y-axis direction along the horizontal direction and an X-axis direction along the vertical direction may also be specified. In a modified example, a reflecting portion 190, 2910 may also be provided outside the coverage area PF, RF of each optical path PL, RL under the detection control Cd in a portion other than the frame member 18 holding the optical unit 2 and the scanning unit 3 in the housing unit 1, such as the housing body 12. In a modified example, the light shielding portion 181 may not be provided around the reflecting portion 190, 2910. In a modified example, for example, the reflecting surface 191, 2191 may be formed to be inclined toward the side opposite to the light-transmitting window 16 in the X-axis direction along an acute angle direction relative to the YZ plane and the XY plane, thereby giving the reflecting portion 190, 2190 a regular reflection characteristic instead of a diffuse reflection characteristic.

[0076] In a modified embodiment, the mobile object to which the optical sensor 100 is applied may be, for example, an autonomous robot capable of autonomous or remotely operated transportation of goods or information collection. In a modified embodiment, the optical sensor 100 may be applied to a stationary structure in addition to a mobile object.

[0077] (Supplementary explanation)

[0078] This specification discloses the following technical concepts and their combinations.

[0079] (Technical Thought 1)

[0080] An optical sensor (100) receives a reflected beam (RB) reflected from a projected beam (PB),

[0081] The optical sensor (100) has:

[0082] A shell unit (1) separates the outside from the inside;

[0083] An optical unit (2) comprising a light projecting portion (20) and a light receiving portion (40), wherein the light projecting portion projects the light beam within the housing unit, and the light receiving portion receives the reflected beam within the housing unit;

[0084] a scanning unit (3) for scanning the projected light beam from the light projecting portion toward the outside world within the housing unit and reflecting the reflected light beam from the outside world toward the light receiving portion within the housing unit; and

[0085] A control unit (5) controls the optical unit and the scanning unit,

[0086] The housing unit has a reflecting portion (190, 2190) which is endowed with a reflecting property for the projection beam.

[0087] The control unit is configured to perform detection control (Cd) and monitoring control (Cm), wherein the detection control (Cd) corresponds to the scanning unit forming each optical path (PL, RL) between the optical unit and the outside world in the shell unit using the projection beam and the reflection beam to overlap the coverage areas (PF, RF) with each other to detect the outside world; and the monitoring control (Cm) corresponds to the scanning unit forming each optical path between the reflecting part and the optical unit to monitor the optical characteristics of the optical unit, wherein the reflecting part is arranged in the shell unit outside the coverage area of ​​each optical path under the detection control.

[0088] (Technical Thought 2)

[0089] According to the optical sensor described in the technical idea 1, the reflecting unit imparts the reflecting characteristics to the reflecting surface (191, 2191) that diffusely reflects the projected light beam.

[0090] (Technical Thought 3)

[0091] According to the optical sensor described in the technical idea 1 or 2, the light projecting unit projects the light beam in a linear shape having a long side along the reference direction (Y) at least to the outside world.

[0092] The reflecting portion (190) imparts the reflecting property to a reflecting surface (191) having a long side along the reference direction.

[0093] (Technical Thought 4)

[0094] According to the optical sensor described in the technical concept 1 or 2, the light projection unit projects the light projection beam in the form of a linear beam having a long side along the reference direction at least to the outside world by a collection of individual beams (PBi) from a plurality of light sources (24) arranged separately along the reference direction (Y).

[0095] The plurality of reflecting portions (2190) are arranged separately along the reference direction, and each imparts the reflecting characteristic to the individual beams from the corresponding light sources.

[0096] (Technical Thought 5)

[0097] According to the optical sensor described in the fourth technical idea, the light projecting unit projects the linear light beam having a long side along the reference direction by gathering the individual beams overlapping in the reference direction in the arrangement region of the reflector.

[0098] (Technical Thought 6)

[0099] According to the optical sensor described in any one of technical ideas 1 to 5, the reflecting portion is arranged in a region opposite to the optical unit across the scanning unit in a frame member (18) that holds the optical unit and the scanning unit in the housing unit.

[0100] (Technical Thought 7)

[0101] According to the optical sensor described in any one of technical ideas 1 to 6, the shell unit has a shading portion (181) that is endowed with shading properties for the projected beam and the reflected beam, and the shading portion (181) is located around the reflecting portion outside the coverage area of ​​each of the optical paths under the detection control within the shell unit.

[0102] (Technical Thought 8)

[0103] According to the optical sensor described in any one of technical ideas 1 to 7, the shell unit has a light-transmitting window (16) avoiding the configuration area of ​​the reflecting part within the coverage area of ​​each light path under the detection control in the shell unit, and the light-transmitting window (16) is given light-transmitting characteristics for the projected beam and the reflected beam between the outside world and the inside of the shell unit.

Claims

1. An optical sensor (100) receiving a reflected beam (RB) reflected from a projected beam (PB), The optical sensor features: A shell unit (1) separates the outside from the inside; An optical unit (2) comprising a light projecting portion (20) and a light receiving portion (40), wherein the light projecting portion projects the light beam within the housing unit, and the light receiving portion receives the reflected beam within the housing unit; a scanning unit (3) for scanning the projected light beam from the light projecting portion toward the outside world within the housing unit and reflecting the reflected light beam from the outside world toward the light receiving portion within the housing unit; as well as A control unit (5) controls the optical unit and the scanning unit, The housing unit has a reflective portion (190, 2190) which is endowed with a reflective property for the projection beam. The control unit is configured to perform detection control (Cd) and monitoring control (Cm), wherein the detection control corresponds to the scanning unit forming each optical path (PL, RL) between the optical unit and the outside world to detect the outside world, and each optical path makes the coverage area (PF, RF) overlap with each other through the projection beam and the reflection beam in the shell unit; the monitoring control corresponds to the scanning unit forming each optical path between the reflecting part and the optical unit to monitor the optical characteristics of the optical unit, and the reflecting part is arranged in the shell unit outside the coverage area of ​​each optical path under the detection control.

2. The optical sensor according to claim 1, The reflecting portion imparts the reflecting characteristics to a reflecting surface (191, 2191) that diffusely reflects the projected light beam.

3. The optical sensor according to claim 1, The light projecting unit projects the light beam in a linear shape having a long side along a reference direction (Y) at least toward the outside world. The reflecting portion (190) imparts the reflecting property to a reflecting surface (191) having a long side along the reference direction.

4. The optical sensor according to claim 1, The light projection unit projects the light projection beam in the form of a linear beam having a long side along the reference direction at least to the outside world by gathering individual beams (PBi) from a plurality of light sources (24) arranged separately along the reference direction (Y). The plurality of reflecting portions (2190) are arranged separately along the reference direction, and respectively apply the reflecting characteristics to the individual beams from the corresponding light sources.

5. The optical sensor according to claim 4, The light projecting unit projects the light projection beam in a linear shape having a long side along the reference direction by gathering the individual beams that overlap in the reference direction in the arrangement region of the reflector.

6. The optical sensor according to any one of claims 1 to 5, The reflecting portion is arranged in a region opposite to the optical unit across the scanning unit in a frame member (18) that holds the optical unit and the scanning unit in the housing unit.

7. The optical sensor according to any one of claims 1 to 5, The housing unit has a shading portion (181) having shading properties for the projected beam and the reflected beam, and the shading portion is located around the reflecting portion outside the coverage area of ​​each of the optical paths under the detection control in the housing unit.

8. The optical sensor according to any one of claims 1 to 5, The shell unit has a light-transmitting window (16) in the coverage area of ​​each of the optical paths under the detection control in the shell unit, avoiding the configuration area of ​​the reflective portion, and the light-transmitting window is given light-transmitting characteristics for the projected beam and the reflected beam between the outside world and the inside of the shell unit.

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