Optical Module and Distance Measuring Device

Abstract

The optical module according to the present disclosure is provided with: a light emitting unit (10) capable of emitting light; a light receiving unit (20) having a first light receiving unit and a second light receiving unit; a first cover unit (30) provided on the light emitting side of the light emitting unit (10), capable of guiding a first light (L1) which is a part of the light emitted from the light emitting unit (10) in the direction of the target (2), and capable of guiding a second light (L2) which is another part of the light emitted from the light emitting unit (10) in a direction different from the direction of the target (2); and a second cover unit (40) provided on the light incident side of the light receiving unit (20), capable of guiding a reflected light (L1R) formed by the first light (L1) reflected by the target (2) in the direction of the first light receiving unit, and capable of guiding the second light (L2) guided from the first cover unit (30) in the direction of the second light receiving unit.

Description

Technical Field

[0001] The present disclosure relates to a distance measuring device for measuring a distance to a target, and an optical module used in the distance measuring device. Background Art

[0002] The distance measuring device uses, for example, a passive method in which light is not applied and an active method in which light is applied. The passive method includes a multi-eye method and the like, and the active method includes a TOF (Time of Flight) method and the like.

[0003] The TOF method is a method of measuring the delay time of light reflected back from a target to be measured, and measuring the distance to the target based on the delay time (for example, see Patent Document 1).

[0004] Citation List

[0005] Patent Literature

[0006] PTL 1: U.S. Unexamined Patent Application Publication No. 2018 / 0026058. Summary of the invention

[0007] Incidentally, in a distance measuring device, it is desirable to more easily provide an optical path for calibrating a distance to a distance measuring target obtained from the distance measuring device.

[0008] It is desirable to provide a distance measuring device capable of more easily providing an optical path for calibrating the distance to a distance measuring target, and an optical module used in the distance measuring device.

[0009] An optical module according to an embodiment of the present disclosure includes a light emitting portion, a light receiving portion, a first cover portion, and a second cover portion. The light emitting portion is configured to emit light. The light receiving portion includes a first light receiving portion and a second light receiving portion. The first cover portion is disposed on a light emitting side of the light emitting portion. The first cover portion is configured to guide a first light as a part of the light emitted from the light emitting portion in a target direction, and to guide a second light as another part of the light emitted from the light emitting portion in a direction different from the direction of the target. The second cover portion is disposed on a light incident side of the light receiving portion. The second cover portion is configured to guide a reflected light as the first light reflected by the target in the direction of the first light receiving portion, and to guide the second light guided from the first cover portion in the direction of the second light receiving portion.

[0010] A distance measuring device according to an embodiment of the present disclosure includes a light emitting unit, a light receiving unit, a first cover unit, a second cover unit, and a processor. The light emitting unit is configured to emit light. The light receiving unit includes a first light receiving unit and a second light receiving unit. The first cover unit is disposed on the light emitting side of the light emitting unit. The first cover unit is configured to guide a first light as a part of the light emitted from the light emitting unit in a target direction, and to guide a second light as another part of the light emitted from the light emitting unit in a direction different from the direction of the target. The second cover unit is disposed on the light incident side of the light receiving unit. The second cover unit is configured to guide a reflected light as the first light reflected by the target in the direction of the first light receiving unit, and to guide the second light guided from the first cover unit in the direction of the second light receiving unit. The processor is configured to calculate the distance to the target based on a first pixel signal output from the first light receiving unit in response to the reflected light incident on the first light receiving unit. The processor is also configured to calibrate the distance based on a second pixel signal output from the second light receiving unit in response to the second light incident on the second light receiving unit.

[0011] In an optical module according to an embodiment of the present disclosure, first light, which is a part of the light emitted from the light emitting portion, is transmitted through the first cover portion to enter the target, and reflected light from the target is transmitted through the second cover portion to enter the first light receiving portion. On the other hand, second light, which is another part of the light emitted from the light emitting portion, is guided by the first cover portion in a direction different from the target, and is guided by the second cover portion to the second light receiving portion to enter the second light receiving portion.

[0012] In a distance measuring device according to one embodiment of the present disclosure, a first light which is a part of the light emitted from the light emitting portion is transmitted through the first cover portion into the target, and a reflected light from the target is transmitted through the second cover portion into the first light receiving portion. Then, based on the first pixel signal from the first light receiving portion, the distance to the target is calculated. On the other hand, a second light which is another part of the light emitted from the light emitting portion is guided by the first cover portion in a direction different from the target, and is guided by the second cover portion to the second light receiving portion and enters the second light receiving portion. Then, based on the second pixel signal from the second light receiving portion, the distance to the target is calibrated. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] [ Figure 1 ] Figure 1 is a schematic diagram showing an example configuration of a distance measuring device according to an embodiment of the present disclosure.

[0014] [ Figure 2 ] Figure 2 yes Figure 1 A perspective view of an example configuration of the main parts of a distance measuring device is shown.

[0015] [ Figure 3 ] Figure 3 yes Figure 1A perspective view of an example configuration of a light emitting section and a light receiving section of a distance measuring device shown.

[0016] [ Figure 4 ] Figure 4 yes Figure 1 A plan view of an example configuration of a light emitting section and a light receiving section of a distance measuring device shown.

[0017] [ Figure 5 ] Figure 5 yes Figure 1 A perspective view of an example configuration of a first cover portion and a second cover portion of a distance measuring device is shown.

[0018] [ Figure 6 ] Figure 6 yes Figure 1 A cross-sectional perspective view of an example configuration of a range finding device is shown.

[0019] [ Figure 7 ] Figure 7 Yes means Figure 1 An explanatory diagram of an example operation of the distance measuring device shown.

[0020] [ Figure 8 ] Figure 8 It is shown in Figure 1 The distance measuring device shown is a timing diagram of a light output waveform of a light emitting unit and a light input waveform of a light receiving unit when the distance measuring device performs distance measurement by a direct method.

[0021] [ Fig. 9 ] Fig. 9 is an explanatory diagram showing a deviation between an actual distance and a distance measured by a distance measuring device using a direct method.

[0022] [ Fig.10 ] Fig.10 is a perspective view showing an example configuration of a main part of a distance measuring device according to Modification 1.

[0023] [ Fig.11 ] Fig.11 yes Fig.10 A perspective view of an example configuration of a recess of a first cover portion of a distance measuring device is shown.

[0024] [ Fig.12 ] Fig.12 yes Fig.10 A plan view of an example configuration of a first light-receiving pixel and a second light-receiving pixel of a ranging device shown.

[0025] [ Fig.13 ] Fig.13 2 is a plan view showing an example configuration of first and second light-receiving pixels of a distance-measuring device according to Modification 2.

[0026] [ Fig.14 ] Fig.14 is a perspective view of an example configuration of a main part of a distance measuring device according to Modification 3.

[0027] [ Fig.15 ] Fig.15 is a perspective view of an example configuration of a main part of a distance measuring device according to Modification 4.

[0028] [ Fig.16 ] Fig.16 is a perspective view of an example configuration of a main part of a distance measuring device according to Modification 5.

[0029] [ Fig.17 ] Fig.17 yes Fig.16 A cross-sectional perspective view of the configuration of the distance measuring device is shown.

[0030] [ Fig.18 ] Fig.18 is a perspective view of an example configuration of a main part of a distance measuring device according to Modification 6.

[0031] [ Fig.19 ] Fig.19 2 is a plan view showing an example configuration of a light emitting section and a light receiving section of a distance measuring device according to Modification 7.

[0032] [ Fig. 20 ] Fig. 20 1 is a timing chart showing a light output waveform of a light emitting section and a light input waveform of a light receiving section in the case of performing distance measurement by an indirect method.

[0033] [ Fig.21 ] Fig.21 This is an explanatory diagram for explaining the deviation between the actual distance and the distance measured by the distance measuring device using the indirect method.

[0034] [ Fig. 22 ] Fig. 22 is a block diagram showing an example of a schematic configuration of a vehicle control system. .

[0035] [ Fig.23 ] Fig.23 It is an auxiliary diagram for explaining an example of the installation positions of the vehicle exterior information detection section and the imaging section.

[0036] [ Fig.24 ] Fig.24 is a plan view of an example configuration of a light receiving section of a distance measuring device according to a modification. DETAILED DESCRIPTION

[0037] Hereinafter, embodiments of the present disclosure are described in detail with reference to the accompanying drawings. Note that the description is given in the following order.

[0038] 1. Embodiment (Example in which the first and second cover parts are provided with grooves having a reflective surface)

[0039] 2. Modification 1 (Example in which the reflecting surface of the second cover portion and the second light receiving portion are arranged to extend in one direction)

[0040] 3. Modification 2 (Example in which the second light receiving section is configured to include a plurality of pixels)

[0041] 4. Modification 3 (Example in which the reflecting surface of the second cover portion and the second light receiving portion are arranged to extend in one direction)

[0042] 5. Modification 4 (Example in which the reflecting surface of the second cover portion is arranged to extend in one direction)

[0043] 6. Modification 5 (Example in which the first and second cover parts are integrally constructed)

[0044] 7. Modification 6 (Example in which the first and second cover parts are provided with protrusions having a reflective surface)

[0045] 8. Modification 7 (Example where the position of the second light receiving section is shifted from the shortest line coupling the pixel included in the first light receiving section and the monitoring light emitter)

[0046] 9. Modification 8 (Example of performing distance measurement by indirect method)

[0047] 10. Examples of application to mobile bodies

[0048] <1. Example>

[0049] [Configuration Example]

[0050] Figure 1 An example configuration of a distance measuring device (distance measuring device 1) according to an embodiment is shown. The distance measuring device 1 is a device that irradiates a distance measuring target 2 with light L1, detects reflected light L1R reflected by the distance measuring target 2, and measures the distance to the distance measuring target 2 based on the detection result. The distance measuring device 1 includes a light emitting unit 10, a light receiving unit 20, a first cover unit 30, a second cover unit 40, and a processor 50. In the distance measuring device 1, the light emitting unit 10, the light receiving unit 20, the first cover unit 30, and the second cover unit 40 can be configured as an optical module.

[0051] The light emitting portion 10 includes, for example, any light emitting body used as a light source, such as a laser (LASER (Light Amplification by Stimulated Emission)) or an LED (Light Emitting Diode), and is configured to emit light. The laser may include, for example, a VCSEL (Vertical Cavity Surface Emitting Laser). The light emitted from the light emitting portion 10 is, for example, infrared light. In addition, the light emitted from the light emitting portion 10 is, for example, pulsed light. Part of the light (light L1) emitted from the light emitting portion 10 is emitted to the outside through the first cover portion 30 to illuminate the ranging target 2.

[0052] The light receiving unit 20 is configured to receive incident light and convert it into an electrical signal. The light receiving unit 20 has sensitivity to at least the light emitted from the light emitting unit 10. The light receiving unit 20 includes a first light receiving unit 21A and a second light receiving unit 21B. The first light receiving unit 21A includes one or more pixels. The first light receiving unit 21A is configured so that the reflected light L1R emitted from the light emitting unit 10 and reflected by the ranging target 2 is incident through the second cover 40. The first light receiving unit 21A converts the reflected light L1R reflected by the ranging target 2 into a first pixel signal S1, and outputs the first pixel signal S1 to the processor 50. In addition, the second light receiving unit 21B of the light receiving unit 20 includes one or more pixels. The light received by the second light receiving unit 21B and the pixel signal generated by the second light receiving unit 21B will be described later.

[0053] The first cover 30 is provided on the light emitting side of the light emitting portion 10. For example, the first cover 30 is held by a holder or the like so as to be spaced apart from the light emitting portion 10. Alternatively, in the case where the light emitting portion 10 is a packaged light emitting portion, the packaged cover may be configured as the first cover 30. The first cover 30 includes a material that is transparent to the light emitted from the light emitting portion 10, and includes, for example, glass or plastic. The first cover 30 has a plate-like shape as a whole. The first cover 30 prevents dust or the like from being attached to the light emitting portion 10, thereby protecting the light emitting portion 10 from the influence of the external atmosphere.

[0054] In the present embodiment, the first cover portion 30 is partially provided with the first reflecting surface 31. In the portion of the first cover portion 30 where the first reflecting surface 31 is not provided, part of the light emitted from the light emitting portion 10 is emitted through the first cover portion 30 to be guided in the direction of the ranging target 2. The light that is transmitted through the first cover portion 30 and guided in the direction of the ranging target 2 corresponds to the light L1 applied to the ranging target 2. In addition, in the portion of the first cover portion 30 where the first reflecting surface 31 is provided, the other part of the light emitted from the light emitting portion 10 is reflected by the first reflecting surface 31 and guided in a direction different from the direction of the ranging target 2. The light reflected by the first reflecting surface 31 and guided in a direction different from the direction of the ranging target 2 is Figure 1In the figure, it is represented as light L2. In the present embodiment, the first reflecting surface 31 is an inclined surface that is at an angle of 45° relative to the main surface 30P of the first cover portion 30. Here, the main surface 30P of the first cover portion 30 refers to the surface of the first cover portion 30 that is approximately parallel to the XY plane and located on the far side in the Z-axis direction when viewed from the light-emitting portion 10. The light L2 reflected by the first reflecting surface 31 is guided in the direction of the second cover portion 40. As described above, the first cover portion 30 guides part of the light (light L1) emitted from the light-emitting portion 10 to the direction of the ranging target 2, and guides the other part of the light (light L2) emitted from the light-emitting portion 10 to a direction different from the direction of the ranging target 2.

[0055] The second cover 40 is provided on the light incident side of the light receiving part 20. For example, the second cover 40 is held by a holder or the like so as to be spaced apart from the light receiving part 20. Similar to the first cover 30, the second cover 40 includes a material transparent to the light emitted from the light emitting part 10, and includes, for example, glass or plastic. The second cover 40 has a plate-like shape as a whole. The second cover 40 prevents dust and the like from being attached to the light receiving part 20, thereby protecting the light receiving part 20 from the influence of the external atmosphere.

[0056] In the present embodiment, the second cover portion 40 is partially provided with a second reflecting surface 41. In the portion of the second cover portion 40 where the second reflecting surface 41 is not provided, the reflected light L1R reflected by the ranging target 2 is transmitted through the second cover portion 40 to be guided in the direction of the first light receiving portion 21A of the light receiving portion 20. The second reflecting surface 41 is an inclined surface at an angle of 45° relative to the main surface 40P of the second cover portion 40. Here, the main surface 40P of the second cover portion 40 refers to the surface of the second cover portion 40 that is substantially parallel to the XY plane and located on the far side in the Z-axis direction when viewed from the light receiving portion 20. The light L2 reflected by the first reflecting surface 31 and guided to the second cover portion 40 is reflected by the second reflecting surface 41 and guided in the direction of the second light receiving portion 21B of the light receiving portion 20. As described above, the second cover 40 guides the light (reflected light L1R) reflected by the distance measuring target 2 in the direction of the first light receiving portion 21A, and guides the light (light L2) guided from the first cover 30 in the direction of the second light receiving portion 21B.

[0057] The reflected light L1R reflected by the distance measuring target 2 enters the first light receiving part 21A of the light receiving part 20 and is converted into a first pixel signal S1. The first pixel signal S1 is output to the processor 50. In addition, the other part of the light (light L2) emitted from the light emitting part 10 and reflected by the first reflection surface 31 of the first cover part 30 and the second reflection surface 41 of the second cover part enters the second light receiving part 21B of the light receiving part 20 to be converted into a second pixel signal S2. The second pixel signal S2 is output to the processor 50.

[0058] The processor 50 is configured to drive the light emitting section 10 so that each light emitter 11 of the light emitting section 10 emits light. In addition, the processor 50 is configured to calculate the distance between the distance measuring device 1 and the distance measuring target 2 based on the first pixel signal S1 output from the first light receiving section 21A in response to the reflected light L1R incident on the first light receiving section 21A of the light receiving section 20. The processor 50 is also configured to calibrate the distance between the distance measuring device 1 and the distance measuring target 2 based on the second pixel signal S2 output from the second light receiving section 21B in response to the light L2 incident on the second light receiving section 21B of the light receiving section 20 through the first cover section 30 and the second cover section 40.

[0059] In the distance measuring device 1, a light diffuser, an optical filter such as a bandpass filter, a lens or other optical member may be appropriately provided as needed on the optical path through which a part of the light emitted from the light emitting section 10 passes before being reflected by the distance measuring target 2 to enter the first light receiving section 21A of the light receiving section 20. Similarly, a light diffuser, an optical filter such as a bandpass filter, a lens or other optical member may be appropriately provided as needed on the optical path through which the other part of the light emitted from the light emitting section 10 passes before entering the second light receiving section 21B of the light receiving section 20 through the first cover section 30 and the second cover section 40.

[0060] (Detailed configuration example)

[0061] Figure 2 An example configuration of a main portion of the distance measuring device 1 is shown. Figure 2 The light emitting unit 10 , the light receiving unit 20 , the first cover unit 30 and the second cover unit 40 of the distance measuring device 1 are shown. Figure 3 and Figure 4 An example configuration of the light emitting section 10 and the light receiving section 20 of the distance measuring device 1 is shown.

[0062] The light-emitting section 10 includes a light-emitting section substrate 10S and a plurality of light-emitting bodies 11 (light-emitting bodies 11A, 11B, 11C, 11D...) arranged in a matrix on the light-emitting section substrate 10S. Although four times four (four in the X-axis direction and four in the Y-axis direction), i.e., sixteen light-emitting bodies 11, are arranged in the figure, this number is not restrictive, and it is sufficient to provide one or more light-emitting bodies. The light-emitting body 11 includes, for example, a laser such as a VCSEL, an LED, etc. A portion of the light emitted from the light-emitting section 10 is light (light L1) that is guided in the direction of the above-mentioned ranging target 2 to illuminate the ranging target 2. The other portion of the light emitted from the light-emitting section 10 is light (light L2) that enters the second light receiving section 21B of the light receiving section 20 through the first cover portion 30 and the second cover portion 40. The light L2 is also referred to as a monitoring light, and the light-emitting body that emits the light L2 is also referred to as a monitoring light-emitting body 11M. Figure 2 and Figure 3In the figure, one luminous body 11 is shown as the monitoring luminous body 11M; without limitation thereto, two or more luminous bodies 11 may be the monitoring luminous bodies 11M. In addition, the light emitted by one or more luminous bodies 11 may be partially used as the monitoring light.

[0063] The light receiving unit 20 is arranged on the X-axis direction side of the light emitting unit 10. The light receiving unit 20 includes a light receiving unit substrate 20S, and a first light receiving unit 21A and a second light receiving unit 21B arranged on the light receiving unit substrate 20S. When observed from the light emitting unit 10, the first light receiving unit 21A is arranged on the far side of the X-axis direction, and the second light receiving unit 21B is arranged on the near side. The pixels of the first light receiving unit 21A and the second light receiving unit 21B receive incident light and output an electrical signal corresponding to the amount of received light. The first light receiving unit 21A is a pixel array, and includes, for example, n×m (m in the X-axis direction and n in the Y-axis direction) pixels arranged in a matrix (pixels A11 to Anm). Each pixel includes a light receiving element such as a PD (photodiode). In addition, the second light receiving unit 21B includes one pixel. Although shown in the drawings as including one pixel, it may include two or more pixels. The second light receiving unit 21B includes a light receiving element such as a PD. In this example, the first light receiving section 21A and the second light receiving section 21B are configured as separate bodies. Figure 4 In the structure of the light emitting unit 10 and the light receiving unit 20 shown in the figure, in the present embodiment, the second light receiving unit 21B is formed to be smaller than the first light receiving unit 21A in both the X-axis direction and the Y-axis direction. The second light receiving unit 21B is arranged at a position corresponding to the vicinity of the center in the Y-axis direction of the first light receiving unit 21. The second light receiving unit 21B is located on the shortest line (dash-dotted line 10C) connecting the pixels of the first light receiving unit 21A and the monitoring light emitter 11M.

[0064] Figure 5An example configuration of the first cover 30 and the second cover 40 of the distance measuring device 1 is shown. The first cover 30 has a plate-like shape and is partially provided with a first groove 32. A portion of the inner wall of the first groove 32 is a first reflection surface 31, which is an inclined surface at an angle of 45° relative to the main surface 30P of the first cover 30. The inner wall of the first groove 32 is in contact with the air. In the case where the first cover 30 includes glass, the first groove 32 can be formed by countersunk processing, sandblasting, etc. In addition, in the case where the first cover 30 includes plastic, the first groove 32 can be formed by molding. The first reflection surface 31 reflects the monitoring light emitted from the monitoring illuminant 11M according to the difference between the refractive index of the material constituting the first cover 30 and the refractive index of the air, and guides the monitoring light in a direction different from the direction of the distance measuring target 2. In order to increase the reflectivity of the light on the first reflection surface 31, a reflection film including silver or other metal films or the like can be provided on the first reflection surface 31. Alternatively, a light shielding material film can be provided on the first reflection surface 31. Alternatively, the first groove 32 may be filled with a material having a different refractive index from the material constituting the first cover portion 30. Alternatively, the first groove 32 may be filled with a light shielding material. In addition, the first reflective surface 31 may not necessarily be totally reflective or highly reflective. For example, light emitted from the monitoring luminous body 11M and incident on a portion of the first groove 32 may be partially reflected to be used as monitoring light, and the remaining light may be transmitted and guided in the direction of the ranging target 2 to be used as light (light L1) applied to the ranging target 2.

[0065] The second cover 40 has a plate-like shape and is partially provided with a second groove 42. A portion of the inner wall of the second groove 42 is a second reflective surface 41 (which is an inclined surface at an angle of 45° relative to the main surface 40P of the second cover 40). The inner wall of the second groove 42 is in contact with the air. The second groove 42 can be formed in a manner similar to the first groove 32. The second reflective surface 41 reflects the monitoring light emitted from the monitoring luminous body 11M and reflected by the first reflective surface 31 according to the difference between the refractive index of the material constituting the second cover 40 and the refractive index of the air, and guides the monitoring light in the direction of the second light receiving part 21B. In order to increase the reflectivity of the light on the second reflective surface 41, for example, a reflective film including silver or other metal films, etc., can be provided on the second reflective surface 41, a light shielding material film can be provided on the second reflective surface 41, and in addition, a material having a refractive index different from that of the material constituting the second cover 40 can be filled in the second groove 42, or a light shielding material can be filled in the second groove 42. In addition, the second reflective surface 41 may not necessarily be totally reflective or highly reflective.

[0066] The first cover portion 30 and the second cover portion 40 are aligned so that the optical path of the monitor light L2 is provided. The first cover portion 30 and the second cover portion 40 are large enough so that the optical path of the monitor light L2 can be easily adjusted.

[0067] Figure 6 An example cross-sectional structure of the distance measuring device 1 is shown. A holder 101 is provided on a substrate 100. The holder 101 is provided with a light emitting portion opening 101A and a light receiving portion opening 101B. Inside the light emitting portion opening 101A, a packaged light emitting portion 10 is provided on the substrate 100. The packaged light emitting portion 10 is provided with a first cover portion 30 as a cover of the package. The first cover portion 30 is provided with a first reflecting surface 31. In addition, a light diffusion film 33 is formed on the first cover portion 30 for diffusing light emitted from the light emitting portion 10 in the direction of the distance measuring target 2.

[0068] In addition, on the substrate 100, a light receiving unit 20 is arranged inside the light receiving unit opening 101B. The second cover 40 is provided on the light incident side of the light receiving unit 20. The second cover 40 is provided with a second reflective surface 41. In addition, the second cover 40 is provided with an infrared filter 43 for transmission of infrared light as light from the light emitting unit 10. In addition, a lens holder 102 is provided inside the light receiving unit opening 101B. The lens holder 102 holds lenses 103 and 104. In addition, the substrate 100 may be provided with a processor 50 coupled to the light emitting unit 10 and the light receiving unit 20. Alternatively, the light emitting unit 10 and the light receiving unit 20 may be coupled to a separately provided processor 50 via the substrate 100. In addition to the above, other optical components may be appropriately provided in the light emitting unit opening 101A and the light receiving unit opening 101B.

[0069] Here, the light emitting unit 10 corresponds to a specific example of the “light emitting unit” in the present disclosure. The light receiving unit 20 corresponds to a specific example of the “light receiving unit” in the present disclosure. The first cover unit 30 corresponds to a specific example of the “first cover unit” in the present disclosure. The second cover unit 40 corresponds to a specific example of the “second cover unit” in the present disclosure. The processor 50 corresponds to a specific example of the “processor” in the present disclosure.

[0070] [Operation and work]

[0071] Next, the operation and working of the distance measuring device of this embodiment will be described.

[0072] (Overview of overall operation)

[0073] First, refer to Figure 1The outline of the overall operation of the distance measuring device is described. The light emitting section 10 emits light by being driven by the processor 50. A portion of the light (light L1) emitted from the light emitting section 10 passes through the first cover section 30 and is guided in the direction of the distance measuring target 2 to illuminate the distance measuring target 2. The light L1 is reflected by the distance measuring target 2 to become the reflected light L1R, and enters the first light receiving section 21A of the light receiving section 20. The first light receiving section 21A receives the reflected light L1R and outputs the first pixel signal S1 to the processor 50. Based on the first pixel signal S1, the processor 50 calculates the distance to the distance measuring target 2 based on the time taken for the light emitted from the light emitting section 10 to be reflected by the distance measuring target 2 and incident on the light receiving section 20. On the other hand, another portion of the light (monitoring light L2) emitted from the light emitting section 10 is reflected by the first reflection surface 31 of the first cover section 30 to be guided in the direction of the second cover section 40, and is reflected by the second reflection surface 41 of the second cover section 40 to enter the second light receiving section 21B of the light receiving section 20. The second light receiving section 21B receives the monitoring light L2 and outputs the second pixel signal S2 to the processor 50. The processor 50 creates a measurement distance correction value table in advance based on the second pixel signal S2. The processor 50 calculates the distance to the distance measurement target 2 based on the first pixel signal S1, refers to the correction value table to obtain a correction value corresponding to the distance obtained from the first pixel signal S1, and calibrates the distance to the distance measurement target 2 using the obtained correction value.

[0074] (Detailed operation)

[0075] Figure 7 An exemplary operation of the distance measuring device 1 is shown. By being driven by the processor 50 , each light emitter 11 of the light emitting portion 10 emits light in the direction of the first cover portion 30 .

[0076] Part of the light (light L1) incident on the portion of the first cover portion 30 where the first groove 32 is not provided is transmitted through the first cover portion 30 and guided in the direction of the distance measuring target 2 to illuminate the distance measuring target 2. The light L1 is reflected by the distance measuring target 2 to become reflected light L1R, and enters the first light receiving portion 21A of the light receiving portion 20.

[0077] On the other hand, the other part of the light (monitoring light L2) incident on the portion of the first cover portion 30 provided with the first groove 32 is reflected by the first reflecting surface 31 provided in the first groove 32 to be guided in the direction of the second cover portion 40. The monitoring light L2 guided to the second cover portion 40 is reflected by the second reflecting surface 41 provided in the second groove 42 to enter the second light receiving portion 21B of the light receiving portion 20.

[0078] The first light receiving section 21A receives the reflected light L1R and outputs a first pixel signal S1 to the processor 50. Each of the n×m pixels arranged in a matrix in the first light receiving section 21A outputs a first pixel signal S1. In addition, the second light receiving section 21B receives the monitoring light L2 and outputs a second pixel signal S2 to the processor 50.

[0079] For passing Figure 1 The distance measuring device 1 shown in the figure is used to measure the distance to the distance measuring target 2. For example, a direct method and an indirect method can be used; the direct method will be used to describe this embodiment. Based on the first pixel signal S1, the processor 50 measures the time taken for the light emitted from the light emitting unit 10 to be reflected by the distance measuring target 2 and enter the light receiving unit 20, and calculates the distance to the distance measuring target 2 from the obtained time. For each of the n×m pixels of the first light receiving unit 21A, the time taken for the light emitted from the light emitting unit 10 to be reflected by the distance measuring target 2 and enter the light receiving unit 20 is measured, and the distance to the distance measuring target 2 is calculated based on the obtained time. In addition, the processor 50 calibrates the distance to the distance measuring target 2 based on the second pixel signal S2. The details of the calibration will be described later. For each of the n×m pixels of the first light receiving unit 21A, the distance to the distance measuring target 2 is calibrated based on the second pixel signal S2.

[0080] The processor 50 measures the time taken for the light emitted from the light emitting unit 10 to be reflected by the ranging target 2 and enter the light receiving unit 20 based on the first pixel signal S1 output from the first light receiving unit 21A of the light receiving unit 20 by a direct method, and calculates the distance between the ranging device 1 and the ranging target 2 based on the obtained time in the following manner.

[0081] Figure 8 1 shows an example operation in the case where the distance measuring device 1 performs distance measurement by a direct method; (A) shows the light output waveform (transmitted pulse) of the light emitting section 10, and (B) shows the light input waveform (incident pulse) of the light receiving section. Figure 8 (A)) is an output waveform of light immediately after being emitted from the light emitting section 10 and has, for example, a pulse shape.

[0082] The light input waveform of the light receiving unit 20 ( Figure 8 (B) is a waveform of light when the light (reflected light L1R) emitted from the light emitting unit 10 and reflected by the distance measuring target 2 reaches the first light receiving unit 21A of the light receiving unit 20. Figure 8The light input waveform of the light receiving unit 20 has a pulse shape delayed by a delay time DL. The delay time DL corresponds to the time taken for the light emitted from the light emitting unit 10 to be reflected by the ranging target 2 and received by the light receiving unit 20. Therefore, by obtaining the delay time DL, the distance to the ranging target 2 can be calculated.

[0083] In the calculation of the distance to the distance measuring target 2, there may be a deviation between the calculated distance (measured distance) and the actual distance (actual distance). The deviation is caused by circuit delays of the light emitting unit 10, the light receiving unit 20 and the processor 50, for example.

[0084] Fig. 9 FIG. 2 shows an example of the deviation between the actual distance and the distance measured by the distance measuring device 1 in the case where the present technology is applied to the direct method. Fig. 9 In FIG. 1 , the horizontal axis represents the actual distance d1, and the vertical axis represents the measured distance d2 before calibration. In an ideal case where there is no deviation between the measured distance d2 and the actual distance d1, the relationship between the actual distance d1 and the measured distance d2 is represented by a straight line LN1 having a slope of "a1" (a1=1) and an intercept of "0". However, in reality, the relationship between the actual distance d1 and the measured distance d2 is generally represented by a straight line LN2. This straight line LN2 has a slope of "a2" and an intercept of "b". That is, the slope and intercept of the straight line LN2 are different from the slope and intercept of the straight line LN1.

[0085] In the present embodiment, the measured distance is calibrated as follows. The processor 50 corrects the measured distance based on the second pixel signal S2 output from the second light receiving unit 21B in response to the other part of the light (monitoring light L2) incident on the second light receiving unit 21B. Specifically, the processor 50 performs a correction value table creation operation and a normal operation (distance measurement). The correction value table creation operation is performed, for example, before the normal operation. As long as the normal operation is not performed, the correction value table creation operation can be performed at any time. In the correction value table creation operation, the processor 50 creates a correction value table based on the second pixel signal S2. Specifically, while performing control to change the emission moment of the monitoring light L2 to various moments, the processor 50 detects the light receiving moment of the second light receiving unit 21B receiving the monitoring light L2, and finds the measured distance corresponding to each light emission moment based on the second pixel signal S2. On the other hand, the processor 50 multiplies the change amount (time) of the emission moment known to the processor 50 by the speed of light to obtain the actual distance. The processor 50 calculates the difference between the measured distance obtained based on the second pixel signal S2 and the actual distance obtained according to the change amount (time) of the light emission moment. The calculated difference is a correction value corresponding to the measured distance obtained based on the second pixel signal S2. The processor 50 creates a correction value table by obtaining a correction value at each emission moment. In normal operation (distance measurement), based on the first pixel signal S1, the processor 50 measures the time taken until the light emitted from the light emitting section 10 is reflected by the ranging target 2 and enters the light receiving section 20, and calculates the distance to the ranging target 2 based on the obtained time. For each of the n×m pixels of the first light receiving section 21A, the measurement of the time taken until the light emitted from the light emitting section 10 is reflected by the ranging target 2 and enters the light receiving section 20 is performed, and the calculation of the measured distance to the ranging target 2 based on the obtained time is performed. In addition, the processor 50 refers to the correction value table created in advance based on the second pixel signal S2 to obtain a correction value corresponding to the measured distance obtained from the first pixel signal S1, and uses the obtained correction value to correct the measured distance to the ranging target 2. Calibration of the distance to the ranging target 2 is performed for each of the n×m pixels of the first light receiving section 21A.

[0086] In the distance measuring device 1 as described above, in the first cover portion 30, part of the light emitted from the light emitting portion 10 is applied to the distance measuring target 2, and its reflected light L1R enters the first light receiving portion 21A of the light receiving portion 20. The remaining part of the light enters the second light receiving portion 21B of the light receiving portion 20 through the first cover portion 30 and the second cover portion 40. This makes it possible to provide an optical path for the monitoring light L2. A correction value table for distance calibration can be created from the second pixel signal S2 output from the second light receiving portion 21B that receives the monitoring light L2. Therefore, the distance to the distance measuring target 2 can be corrected by referring to the correction value table, which improves the accuracy of the distance to the distance measuring target 2. That is, the distance to the distance measuring target 2 can be corrected based on the second pixel signal S2 output from the second light receiving portion 21B.

[0087] In addition, in the distance measuring device 1, the first cover portion 30 having the first reflecting surface 31 is arranged on the light emitting side of the light emitting portion 10, and the second cover portion 40 having the second reflecting surface 41 is arranged on the light incident side of the light receiving portion 20, so that the optical path of the monitoring light L2 can be easily provided. In addition, the first cover portion 30 and the second cover portion 40 are large enough for adjusting the optical path of the monitoring light L2, which makes it possible to easily adjust the optical path of the monitoring light L2.

[0088] [Effect]

[0089] In the present embodiment as described above, a first cover having a first reflective surface and a second cover having a second reflective surface are provided, which makes it easy to provide an optical path of monitoring light for acquiring a second pixel signal. Therefore, the distance to the distance measurement target can be easily calibrated based on the second pixel signal.

[0090] <2. Modification 1>

[0091] In the above embodiment, the second light receiving portion 21B has a size corresponding to the center of the first light receiving portion 21 in the Y-axis direction, but is not limited thereto. Alternatively, for example, the second light receiving portion 21B may be elongated in one direction D (a direction parallel to the Y-axis direction). In addition, the second reflecting surface 41 of the second cover portion 40 may also extend in one direction D to correspond to the second light receiving portion 21B extending in one direction D.

[0092] Fig.10An example configuration of the main parts of the distance measuring device 1A according to Modification 1 is shown. In this example, the second groove 42 of the second cover portion 40 extends elongated in one direction D, and the second reflection surface 41 is provided to extend elongated in one direction D. In addition, the second light receiving portion 21B is provided in a manner extending elongated in one direction D. The one direction D in which the second reflection surface 41 of the second cover portion 40 and the second light receiving portion 21B extend is, for example, an extension direction (Y-axis direction) of one side on the light emitting portion 10 side of the first light receiving portion 21A.

[0093] Fig.11 An example configuration of the first groove 32 of the first cover 30 of the distance measuring device 1A is shown in an enlarged view. The first reflection surface 31 of the first groove 32 provided in a part of the first cover 30 is provided obliquely with respect to the main surface 30P of the first cover 30, and is also a curved surface convex toward the light receiving unit 20 side. Fig.10 As shown, the first reflection surface 31 as a curved surface reflects the monitor light L2 in a direction different from the direction of the distance measurement target 2 so that the monitor light L2 is diffused in the same direction as the one direction D.

[0094] Fig.12 FIG. 1 shows an example configuration of a first light receiving section 21A and a second light receiving section 21B of a distance measuring device 1A. In this modification, the second light receiving section 21B is a single pixel having a shape elongated in one direction D. The first light receiving section 21A and the second light receiving section 21B are Figure 4 The first light receiving sections 21A shown are the same.

[0095] In the distance measuring device 1A of the present modification, the monitor light L2 of the light emitted from the light emitting section 10 is reflected by the first reflection surface 31 of the first cover section 30, and is guided in the direction of the second cover section 40 so as to be diffused in the same direction as the one direction D. The monitor light L2 diffused in the same direction as the one direction D is reflected by the second reflection surface 41 extending elongated in the one direction D, and is guided in the direction of the second light receiving section 21B extending elongated in the one direction D to enter. Except for the above points, it is similar to the above embodiment.

[0096] In the distance measuring device 1A of this modification, the monitoring light L2 diffuses in the same direction as the one direction D, and is reflected by the second reflecting surface 41 and enters the second light receiving unit 21B which extends elongated in the one direction D. Therefore, this structure makes it easy for the monitoring light L2 to be incident on the second light receiving unit 21B. Therefore, the allowable range of alignment between the first cover portion 30 and the second cover portion 40 in the one direction D is expanded. In addition, the allowable range of alignment between the second cover portion 40 and the light receiving unit 20 (second light receiving unit 21B) in the one direction D is widened. This makes it easy to adjust the optical path of the monitoring light L2.

[0097] <3. Modification 2>

[0098] In the above-described Modification 1, the second light receiving section 21B is configured as a single pixel having a shape extending elongated in one direction D, but is not limited thereto. Alternatively, for example, the second light receiving section 21B may include a plurality of pixels arranged elongated in one direction D.

[0099] Fig.13 An example configuration of the first light receiving section 21A and the second light receiving section 21B of the distance measuring device 1B according to Modification 2 is shown. The second light receiving section 21B includes a plurality of pixels (pixels B1, B2, ..., Bn) arranged elongated in one direction D. Fig.13 In the embodiment, multiple pixels are arranged in a row, but multiple rows are also possible. In this modification, each of the multiple pixels (pixels B1, B2, ..., Bn) can have the same structure as each of the n×m pixels (pixels A11 to Anm) of the first light receiving unit 21A. Except for the above points, it is the same as the above modification 1.

[0100] In the distance measuring device 1B of this modified example, the monitoring light L2 diffuses in the same direction as the one direction D, and is reflected by the second reflecting surface 41 and enters the second light receiving unit 21B arranged elongated in the one direction D. Therefore, this configuration makes it easy for the monitoring light L2 to be incident on the second light receiving unit 21B. Therefore, the allowable range of alignment between the first cover portion 30 and the second cover portion 40 in the one direction D is expanded. In addition, the allowable range of alignment between the second cover portion 40 and the light receiving unit 20 (second light receiving unit 21B) in the one direction D is widened. This makes it easy to adjust the optical path of the monitoring light L2.

[0101] <4. Modification 3>

[0102] In the above-mentioned modification 1, the second groove 42 of the second cover 40 extends elongated in one direction D, and the second reflective surface 41 extends elongated in one direction D, but this example is not limitative. Alternatively, for example, the end surface of the second cover 40 may be the second reflective surface 44 .

[0103] Fig.14 An example configuration of the main part of the distance measuring device 1C according to the modification 3 is shown. In this example, the end surface on the light emitting portion 10 side of the second cover portion 40 is an inclined surface at an angle of 45° relative to the main surface 40P of the second cover portion 40, and the inclined surface is the second reflection surface 44. The second reflection surface 44 is provided in a manner extending elongated in one direction D. In addition, the second light receiving portion 21B is provided in a manner extending elongated in one direction D. It is similar to the above-mentioned modification 1 except that the end surface of the above-mentioned second cover portion 40 is an inclined surface having an angle of 45° relative to the main surface 40P of the second cover portion 40.

[0104] In the distance measuring device 1C of this modification, a surface serving as the second reflecting surface 44 is provided on the end surface of the second cover 40. Compared with forming the second groove in Modification 1, it is easier to process the end surface of the second cover 40 into an inclined surface at an angle of 45° with respect to the main surface 40P of the second cover 40.

[0105] In addition, similarly, the first reflection surface may be provided on the end surface of the first cover portion 30. That is, the end surface on the light receiving portion 20 side of the first cover portion 30 may be an inclined surface at an angle of 45° relative to the main surface 30P of the first cover portion 30, and the inclined surface may be configured as the first reflection surface. In this case, of the light emitted from the light emitting portion 10, the light entering the end surface of the first cover portion 30 is used as the monitoring light L2.

[0106] <5. Modification 4>

[0107] In the above-mentioned modification 3, the second light receiving portion 21B extends elongated in one direction D, but is not limited thereto. Alternatively, for example, the second light receiving portion 21B may not extend elongated in one direction D, but may have a size corresponding to a position near the center of the first light receiving portion 21A in the Y-axis direction.

[0108] Fig.15 An example configuration of the main part of the distance measuring device 1D according to Modification 4 is shown. In this example, the end surface of the second cover portion 40 is a second reflecting surface 44 that extends elongated in one direction D, and the second reflecting surface 44 is arranged to extend elongated in one direction D. In addition, the second light receiving portion 21B does not extend elongated in one direction D, and is arranged to be located at a position corresponding to the vicinity of the center of the first light receiving portion 21A in the Y-axis direction. The one direction D in which the second reflecting surface 44 extends is, for example, an extending direction (Y-axis direction) of one side on the light emitting portion 10 side of the first light receiving portion 21A.

[0109] In the distance measuring device 1D of this modified example, the monitoring light L2 of the light emitted from the light emitting section 10 is reflected by the first reflecting surface 31 of the first cover section 30 to be guided in the direction of the second cover section 40. The monitoring light L2 is reflected by the second reflecting surface 44 and is guided into the direction of the second light receiving section 21B. The first reflecting surface 31 may reflect the monitoring light L2 so that it diffuses in one direction D, or may reflect the monitoring light L2 so that it does not diffuse. In the case where the first reflecting surface 31 diffuses the monitoring light L2 in one direction D, only a portion of the monitoring light L2 diffused in one direction D enters the second light receiving section 21B. In this case, even if the optical path of the monitoring light L2 is offset in one direction D, the light entering the second light receiving section 21B hardly fluctuates. Thus, the allowable range of orientation in one direction D between the second cover section 40 and the light receiving section 20 (second light receiving section 21B) is widened. This makes it possible to easily adjust the optical path of the monitoring light L2. In the case where the first reflecting surface 31 does not diffuse the monitoring light L2 in one direction D, this configuration is similar to Figure 2 The difference of the illustrated configuration is that the second reflective surface 44 is disposed on the end surface of the second cover portion 40, rather than in the second groove 42. Advantageously, the end surface of the second cover portion 40 is easier to process than the second groove 42.

[0110] <6. Modification 5>

[0111] In the above embodiment, the first cover portion 30 and the second cover portion 40 are separate members, but this example is not limitative. Alternatively, for example, the first cover portion 30 and the second cover portion 40 may be integrally configured.

[0112] Fig.16 An example configuration of the main parts of the distance measuring device 1E according to Modification 5 is shown. A common cover 60 that integrates the first cover 30 and the second cover 40 is provided on the light emitting side of the light emitting portion 10 and the light incident side of the light receiving portion 20. For example, the common cover 60 is held by a holder or the like so as to be spaced apart from the light emitting portion 10 and the light receiving portion 20. The common cover 60 includes a material that is transparent to the light emitted from the light emitting portion 10, and includes, for example, glass or plastic. The common cover 60 has a plate-like shape as a whole. The common cover 60 prevents dust and the like from adhering to the light emitting portion 10 and the light receiving portion 20, thereby protecting the light emitting portion 10 and the light receiving portion 20 from the influence of the external atmosphere.

[0113] In this modification, a first reflecting surface 61 is provided in a portion of the common cover 60 on the light emitting portion 10 side. The first reflecting surface 61 is provided on the inner wall of a first groove 62 (provided in a portion of the common cover 60 on the light emitting portion 10 side). The first reflecting surface 61 is an inclined surface at an angle of 45° relative to the main surface 60P of the common cover 60. In addition, a second reflecting surface 63 is provided in a portion on the light receiving portion 20 side of the common cover 60. The second reflecting surface 63 is provided on the inner wall of a second groove 64 (provided in a portion on the light receiving portion 20 side of the common cover 60). The second reflecting surface 63 is an inclined surface at an angle of 45° relative to the main surface 60P of the common cover 60.

[0114] and Figure 1 Similar to the light L1 shown in FIG. 1 , a portion of the light emitted from the light emitting unit 10 is transmitted through the common cover 60 and guided in the direction of the distance measuring target 2, and is reflected by the distance measuring target 2 and enters the first light receiving unit 21A through the common cover 60 again. Figure 1 The other part of the light emitted from the light emitting section 10 is the same as the light L2 shown, and the other part of the light emitted from the light emitting section 10 is reflected on the first reflecting surface 61 to be guided in the direction of the second reflecting surface 63 which is a direction different from the direction of the distance measuring target 2, and is reflected by the second reflecting surface 63 to enter the second light receiving section 21B. The relative position between the first reflecting surface 61 and the second reflecting surface 63 is determined so that the other part of the light emitted from the light emitting section 10 can utilize the optical path reflected by the first reflecting surface 61 and guided in the direction of the second reflecting surface 63, and is reflected by the second reflecting surface 63 to enter the second light receiving section 21B. Except for the above point, it is similar to the above embodiment.

[0115] Fig.17 An example configuration of the distance measuring device 1E is shown. A holder 101 is provided on a substrate 100. A common cover portion 60 is provided on the light emitting side of the light emitting portion 10 and the light incident side of the light receiving portion 20. The common cover portion 60 is held by the holder 101. In the common cover portion 60, a region overlapping with the light emitting portion 10 is partially provided with a first reflection surface 61, and a region overlapping with the second light receiving portion 21B of the light receiving portion 20 is partially provided with a second reflection surface 63. In the region of the common cover portion 60 overlapping with the light emitting portion 10, a light diffusion film 65 for diffusing light emitted from the light emitting portion 10 in the direction of the distance measuring target 2 is formed. In the region of the common cover portion 60 overlapping with the light receiving portion 20, an infrared filter 66 for transmitting infrared light as light from the light emitting portion 10 is provided.

[0116] In the distance measuring device 1E of this modified example, a common cover portion 60 is provided, and the common cover portion 60 has a structure that integrates the first cover portion and the second cover portion. Therefore, the relative position between the first reflection surface 61 and the second reflection surface 63 has been determined. Only by configuring a common cover portion 60 on the light emitting side of the light emitting portion 10 and the light incident side of the light receiving portion 20, the optical path of the monitoring light (light L2) can be provided. Only by adjusting the alignment between the common cover portion 60 and the light receiving portion 2 (second light receiving portion 21B) 0, the first reflection surface 61 and the second reflection surface 63 can be aligned relative to the light emitting portion 10 and the light receiving portion 20, which makes it easy to adjust the optical path of the monitoring light L2.

[0117] <7. Modification 6>

[0118] In the above embodiment, a portion of the inner wall of the first groove 32 is used as the first reflection surface 31, and a portion of the inner wall of the second groove 42 is used as the second reflection surface 41, but this example is not limitative. Alternatively, for example, a portion of the first cover portion 30 may be provided with a first protrusion whose surface is used as the first reflection surface, and a portion of the second cover portion 40 may be provided with a second protrusion whose surface is used as the second reflection surface.

[0119] Fig.18 An example configuration of the main parts of the distance measuring device 1F according to Modification 6 is shown. In this example, the first cover portion 30 is partially provided with the first protrusion 35, and a part of the surface of the first protrusion 35 is the first reflection surface 34. In addition, the second cover portion 40 is partially provided with the second protrusion 46, and a part of the surface of the second protrusion 46 is the second reflection surface 45.

[0120] picture Figure 1 Like the light L1 shown in FIG. 1 , part of the light emitted from the light emitting section 10 is transmitted through the first cover section 30 and guided in the direction of the distance measuring target 2, and is reflected by the distance measuring target 2 and transmitted through the second cover section 40 to enter the first light receiving section 21A. In addition, the other part of the light emitted from the light emitting section 10 is reflected by the first reflecting surface 34 provided on the surface of the first protrusion 35 to be guided in the direction of the second reflecting surface 45 which is a direction different from the direction of the distance measuring target 2, and is reflected by the second reflecting surface 45 which is the surface of the second protrusion 46 to enter the second light receiving section 21B.

[0121] In the distance measuring device 1F of the present modification, a protrusion having a reflective surface is provided on each of the first cover 30 and the second cover 40. This can be preferably performed in a case where it is easy to provide a protruding shape on the surface of the cover, such as plastic molding.

[0122] <8. Modification 7>

[0123] In the above embodiment, the second light receiving section 21B is located on the shortest line coupling the pixels included in the first light receiving section 21A and the monitoring light emitting body 11M, but is not limited thereto. Alternatively, for example, the second light receiving section 21B may be provided at a position offset from the shortest line coupling the pixels included in the first light receiving section 21A and the monitoring light emitting body 11M.

[0124] Fig.19 An example configuration of a light emitting unit and a light receiving unit of a distance measuring device 1G according to variant example 7 is shown. The second light receiving unit 21B is disposed at a position offset from the shortest line coupling the pixels included in the first light receiving unit 21A and the monitoring light emitting body 11M. The dashed line 10C represents the shortest line coupling the pixels included in the first light receiving unit 21A and the pixels included in the monitoring light emitting body 11M, and the second light receiving unit 21B is disposed at a position deviated from the dashed line 10C. In this variant example, the first reflecting surface 31 is configured to adjust its angle so that the first reflecting surface 31 reflects the monitoring light L2 in the direction of the second reflecting surface 41. In addition, the second reflecting surface 41 is configured to adjust its angle so that the second reflecting surface 41 reflects the light incident from the first reflecting surface 31 in the direction of the second light receiving unit 21B. Except for the above points, it is similar to the above-mentioned embodiment.

[0125] The second light receiving section 21B may not necessarily be located on the shortest line connecting the pixels included in the first light receiving section 21A and the monitor light emitter 11M.

[0126] <9. Modification 8>

[0127] The above embodiment describes an example of measuring the distance from the distance measuring device 1 to the distance measuring target 2 by a direct method, but the present invention is not limited thereto. Alternatively, for example, the distance can be measured by an indirect method. An example of measuring the distance by an indirect method is described below.

[0128] Fig. 20 1 shows an example operation in the case where the distance measuring device 1 performs distance measurement by an indirect method; (A) shows the light output waveform (transmitted pulse) of the light emitting unit 10, and (B) and (C) show the light input waveform (incident pulse) of the light receiving unit. In this example, the light output waveform ( Fig. 20 (A)) is, for example, a pulse waveform with a duty cycle of 50%.

[0129] The light input waveform of the light receiving unit 20 ( Fig. 20 (B) and (C)) have relative Fig. 20The pulse shape shown in (A) is a pulse shape delayed by a predetermined time. The delay time of the pulse corresponds to the time until the light (reflected light L1R) emitted from the light emitting unit 10 and reflected by the ranging target 2 reaches the first light receiving unit 21A of the light receiving unit 20. Therefore, the distance to the ranging target 2 can be calculated based on the delay time.

[0130] In the indirect method, the pixel of the first light receiving section 21A accumulates the signal charge Q1 in any period of the period T1 in which the light emitting section 10 emits light, accumulates the signal charge Q2 in any period of the period T2 in which the light emitting section 10 does not emit light, and obtains the charge ratio between the signal charge Q1 and the signal charge Q2. Fig. 20 In the examples of (B) and (C), the pixel of the first light receiving section 21A accumulates the signal charge Q1 by detecting the incident pulse in the period TA of the period T1, and accumulates the signal charge Q2 by detecting the incident pulse in the period TB of the period T2. Fig. 20 In the example of (B), the charge ratio of the signal charge Q1 to the signal charge Q2 is approximately 3:1, and Fig. 20 In the example of (C), the charge ratio of the signal charge Q1 to the signal charge Q2 is approximately 1:1. Therefore, the charge ratio of the signal charge Q1 to the signal charge Q2 varies according to the delay time of the incident pulse. Therefore, by obtaining the charge ratio, the delay time can be obtained with high precision in units of, for example, picoseconds to nanoseconds. If the delay time is converted into the distance to the ranging target 2, for example, when measuring with a delay time in the order of picoseconds to nanoseconds, the distance to the ranging target 2 can be obtained with a resolution of 0.3mm to 30cm. It should be noted that the time period during which the signal charge Q1 is accumulated in the time period T1 when the light-emitting portion 10 emits light, and the time period during which the signal charge Q2 is accumulated in the time period T2 when the light-emitting portion 10 does not emit light, can be appropriately changed.

[0131] In the above calculation of the distance to the ranging target 2, there may be a deviation between the distance obtained by calculation (measured distance) and the actual distance (actual distance). This is due to, for example, circuit delays of the light emitting unit 10, the light receiving unit 20, and the processor 50, the circuit configuration of the light receiving unit 20, the shape of the transmission pulse, etc.

[0132] Fig.21An example of the deviation between the actual distance and the distance measured by the distance measuring device 1 is shown in the case where the present technology is applied to the indirect method. In the ideal case where there is no deviation between the measured distance and the actual distance, the relationship between the actual distance d1 and the measured distance d2 is represented by a straight line LN3 having a slope "a1" (a1=1) and an intercept "0". However, in reality, the relationship between the actual distance d1 and the measured distance d2 is generally as shown by a curve LN4. The curve LN4 has a waviness component c. The straight line LN5 obtained by removing the waviness component c from the curve LN4 has a slope "a2" and an intercept "b". That is, the slope and intercept of the straight line LN5 are different from the slope and intercept of the straight line LN3.

[0133] In the present embodiment, the measured distance is calibrated as follows. The processor 50 corrects the measured distance based on the second pixel signal S2 output from the pixel of the second light receiving unit 21B in response to the other part of the light (monitoring light L2) incident on the second light receiving unit 21B. Specifically, the processor 50 performs a correction value table creation operation and a normal operation (distance measurement) in a manner similar to the operation in the above-mentioned direct method. In the correction value table creation operation, the processor 50 creates a correction value table by detecting the light receiving moment of the second light receiving unit 21B receiving the monitoring light L2 and controlling the emission moment of the monitoring light L2 to change to various moments. In normal operation (ranging), the processor 50 calculates the distance to the ranging target 2 based on the first pixel signal S1, refers to the correction value table to obtain the correction value, and calibrates the measured distance to the ranging target 2.

[0134] As described above, the present technology is also applicable to the indirect method. The time taken for the light emitted from the light emitting unit 10 to be reflected by the ranging target 2 and received by the light receiving unit 20, and the distance to the ranging target 2 converted from the time can be measured more accurately. In addition, the distance to the ranging target 2 obtained by the indirect method can also be calibrated based on the second pixel signal S2 output from the second light receiving unit 21B.

[0135] The above-described embodiment and modifications 1 to 8 may be appropriately combined as needed.

[0136] <10. Application in mobile phones>

[0137] The technology according to the present disclosure (the present technology) is applicable to a variety of products. For example, the technology according to the present disclosure can be implemented as an apparatus installed in a vehicle, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility tool, an airplane, a drone, a ship, or a robot.

[0138] Fig. 22: is a block diagram showing an example of a schematic configuration of a vehicle control system as an example of a moving body control system to which the technology according to the embodiment of the present disclosure can be applied.

[0139] The vehicle control system 12000 includes a plurality of electronic control units connected to each other via a communication network 12001. Fig. 22 In the example shown, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an external information detection unit 12030, an internal information detection unit 12040, and an integrated control unit 12050. In addition, a microcomputer 12051, a sound / image output unit 12052, and an in-vehicle network interface (I / F) 12053 are shown as the functional configuration of the integrated control unit 12050.

[0140] The drive system control unit 12010 controls the operation of the devices related to the drive system of the vehicle according to various programs. For example, the drive system control unit 12010 is used as a control device to control: a drive force generating device for generating the drive force of the vehicle, such as an internal combustion engine, a drive motor, etc., a drive force transmitting mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating the braking force of the vehicle, etc.

[0141] The body system control unit 12020 controls the operation of various types of equipment configured for the body according to various programs. For example, the body system control unit 12020 is used as a control device to control the following items: a keyless entry system, a smart key system, a power window device, or various lights such as headlights, reverse lights, brake lights, turn signals, fog lights, etc. In this case, the body system control unit 12020 can receive as input radio waves transmitted from a mobile device that replaces the key or signals from various switches. The body system control unit 12020 receives these input radio waves or signals to control the door lock device, power window device, lights, etc. of the vehicle.

[0142] The vehicle exterior information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, the vehicle exterior information detection unit 12030 is connected to an imaging unit 12031. The vehicle exterior information detection unit 12030 causes the imaging unit 12031 to image an image of the vehicle exterior, and receives the imaged image. Based on the received image, the vehicle exterior information detection unit 12030 may perform a process of detecting an object (such as a person, vehicle, obstacle, sign, symbol, etc. on the road), or perform a process of detecting the distance to the object.

[0143] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal corresponding to the amount of light received. The imaging unit 12031 can output the electrical signal as an image, or can output the electrical signal as information about the measured distance. In addition, the light received by the imaging unit 12031 may be visible light, or may be invisible light such as infrared rays.

[0144] The in-vehicle information detection unit 12040 detects information about the interior of the vehicle. The in-vehicle information detection unit 12040 may be connected to a driver state detection unit 12041 that detects the state of the driver. The driver state detection unit 12041 includes, for example, a camera that photographs the driver. Based on the detection information input from the driver state detection unit 12041, the in-vehicle information detection unit 12040 may calculate the driver's fatigue level or the driver's concentration level, or may distinguish whether the driver is dozing off.

[0145] The microcomputer 12051 can calculate a control target value for a driving force generation device, a steering mechanism, or a braking device based on information about the interior or exterior of the vehicle obtained by the vehicle exterior information detection unit 12030 or the vehicle interior information detection unit 12040, and output a control command to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing functions of an advanced driver assistance system (ADAS), including collision avoidance or impact buffering for the vehicle, following driving based on vehicle-to-vehicle distance, vehicle speed maintenance driving, an alarm for vehicle collision, an alarm for vehicle lane deviation, and the like.

[0146] In addition, the microcomputer 12051 can control the driving force generating device, the steering mechanism, and the braking device based on the information about the outside or inside of the vehicle obtained by the outside information detection unit 12030 or the inside information detection unit 12040, thereby performing collaborative control intended for automatic driving, etc. that is independent of the driver's operation.

[0147] In addition, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the information about the exterior of the vehicle obtained by the exterior information detection unit 12030. For example, the microcomputer 12051 can control the headlights to change from high beam to low beam based on the position of the preceding vehicle or oncoming vehicle detected by the exterior information detection unit 12030, thereby performing cooperative control aimed at preventing glare by controlling the headlights.

[0148] The sound / image output unit 12052 transmits an output signal of at least one of sound and image to an output device, which can notify information to the passengers of the vehicle or the outside of the vehicle in a visual or auditory manner. Fig. 22In the example of FIG. 1206 , an audio speaker 12061, a display portion 12062, and an instrument panel 12063 are shown as output devices. The display portion 12062 may include, for example, at least one of an in-vehicle display and a head-up display.

[0149] Fig.23 12031 is a diagram showing an example of the installation position of the imaging unit 12031.

[0150] exist Fig.23 In the figure, the imaging unit 12031 includes imaging units 12101, 12102, 12103, 12104 and 12105.

[0151] The imaging units 12101, 12102, 12103, 12104 and 12105 may be arranged at the positions of the front nose, side mirrors, rear bumper, rear door and the upper portion of the windshield inside the vehicle 12100. The imaging unit 12101 arranged at the front nose and the imaging unit 12105 arranged at the upper portion of the windshield inside the vehicle mainly obtain images in front of the vehicle 12100. The imaging units 12102 and 12103 arranged at the side mirrors mainly obtain images of the sides of the vehicle 12100. The imaging unit 12104 arranged at the rear bumper or rear door mainly obtains images of the rear of the vehicle 12100. The imaging unit 12105 arranged at the upper portion of the windshield inside the vehicle is mainly used to detect the front vehicle, pedestrians, obstacles, signals, traffic signs, lanes, etc.

[0152] By the way, Fig.23 An example of the shooting range of the imaging units 12101 to 12104 is shown. Imaging range 12111 represents the imaging range of the imaging unit 12101 arranged at the front nose. Imaging ranges 12112 and 12113 respectively represent the imaging ranges of the imaging units 12102 and 12103 arranged at the side mirrors. Imaging range 12114 represents the imaging range of the imaging unit 12104 arranged at the rear bumper or the rear door. For example, a bird's-eye view image of the vehicle 12100 observed from above can be obtained by superimposing the image data imaged by the imaging units 12101 to 12104.

[0153] At least one of the imaging units 12101 to 12104 may have a function of obtaining distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera composed of a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection.

[0154] For example, the microcomputer 12051 can determine the distance to each three-dimensional object within the imaging ranges 12111 to 12114 and the time change of the distance (relative speed relative to the vehicle 12100) based on the distance information obtained from the imaging units 12101 to 12104, and thereby extract the nearest three-dimensional object as the leading vehicle, which specifically exists on the driving path of the vehicle 12100 and travels at a predetermined speed (e.g., equal to or greater than 0 km / h) in the substantially same direction as the vehicle 12100. In addition, the microcomputer 12051 can pre-set the following distance to be maintained from the leading vehicle, and perform automatic braking control (including following parking control), automatic acceleration control (including following starting control), etc. Therefore, cooperative control intended for automatic driving, etc. that does not depend on the operation of the driver, can be performed.

[0155] For example, the microcomputer 12051 can classify the three-dimensional object data about the three-dimensional object into three-dimensional object data of two-wheeled vehicles, standard-sized vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects based on the distance information obtained from the imaging units 12101 to 12104, and extract the classified three-dimensional object data for automatic avoidance of obstacles. For example, the microcomputer 12051 distinguishes whether the obstacles around the vehicle 12100 are obstacles that can be visually identified by the driver of the vehicle 12100, or obstacles that are difficult for the driver of the vehicle 12100 to visually identify. Then, the microcomputer 12051 determines the collision risk, which indicates the risk of collision with each obstacle. In the case where the collision risk is equal to or higher than the set value and there is a possibility of collision, the microcomputer 12051 outputs an alarm to the driver via the audio speaker 12061 or the display unit 12062, and performs forced deceleration or avoidance steering via the drive system control unit 12010. Thus, the microcomputer 12051 can assist driving to avoid collisions.

[0156] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 is capable of identifying pedestrians by determining whether there are pedestrians in the imaging images of the imaging units 12101 to 12104. This pedestrian recognition is performed, for example, by the following programs: a program for extracting characteristic points in the imaging images of the imaging units 12101 to 12104 as infrared cameras, and a program for determining whether it is a pedestrian by performing pattern matching processing on a series of characteristic points representing the contour of the object. When the microcomputer 12051 determines that there are pedestrians in the imaging images of the imaging units 12101 to 12104 and thus identifies the pedestrians, the sound / image output unit 12052 controls the display unit 12062 to display a square outline superimposed on the identified pedestrian for emphasizing the identified pedestrian. The sound / image output unit 12052 can also control the display unit 12062 to display an icon representing a pedestrian at a desired position.

[0157] An example of a vehicle control system to which the technology according to the present disclosure can be applied has been described above. The technology according to the present disclosure can be applied to the imaging unit 12031 among the above components. Specifically, Figure 1 The distance measuring device 1 shown is applicable to the imaging section 12031. Applying the technology according to the present disclosure to the imaging section 12031 enables accurate measurement of the distance to, for example, a preceding vehicle, a following vehicle, or another object.

[0158] Although the present technology has been described above with reference to some embodiments and modifications, the present technology is not limited to these embodiments and the like, and may be modified in various ways.

[0159] The above embodiment has described a distance measuring device that measures the distance to a distance measuring target, but this example is non-limiting. Alternatively, it may be a time measuring device that illuminates a target with light and measures the time it takes until the light returns.

[0160] In the above embodiments and modifications, Fig.13 As shown in FIG. 1 and FIG. 2 , the first light receiving unit 21A and the second light receiving unit 21B are provided separately, but are not limited thereto. Alternatively, for example, the first light receiving unit 21A and the second light receiving unit 21B may be provided separately. Fig.24 Specifically, for example, one pixel array may be divided into two areas; one may be the first light receiving section 21A, and the other may be the second light receiving section 21B. Fig.24 , each of the plurality of pixels (pixels B1 , B2 , . . . , Bn) of the second light receiving section 21B may have the same structure as each of the n×m pixels (pixels A11 to Anm) of the first light receiving section 21A.

[0161] It is to be noted that the effects described in this specification are merely illustrative and not restrictive, and other effects may be provided.

[0162] It should be noted that the present technology may have the following configuration. According to the present technology having the following configuration, an optical path for calibrating the distance to a distance measurement target can be provided more easily.

[0163] (1) An optical module comprising:

[0164] a light emitting portion configured to emit light;

[0165] A light receiving unit, comprising a first light receiving unit and a second light receiving unit;

[0166] a first cover portion provided on a light emitting side of the light emitting portion and configured to guide first light which is a part of the light emitted from the light emitting portion in a target direction and to guide second light which is another part of the light emitted from the light emitting portion in a direction different from the target direction; and

[0167] The second cover is provided on the light incident side of the light receiving portion and is configured to guide reflected light as first light reflected by the object in the direction of the first light receiving portion and guide second light guided from the first cover in the direction of the second light receiving portion.

[0168] (2) The optical module according to (1), wherein the first cover has a first reflection surface in a portion of the first cover, the first reflection surface being provided obliquely with respect to a main surface of the first cover and configured to reflect the second light in a direction different from a direction of the target.

[0169] (3) The optical module according to (2), wherein

[0170] The first cover portion has a first groove disposed in a portion of the first cover portion, and

[0171] The first reflective surface is the inner wall of the first groove.

[0172] (4) The optical module according to (2), wherein the first reflective surface is an end surface of the first cover portion.

[0173] (5) An optical module according to any one of (1) to (4), wherein the second cover has a second reflection surface in a portion of the second cover, the second reflection surface being arranged obliquely relative to a main surface of the second cover and configured to reflect the second light in a direction of the second light receiving portion.

[0174] (6) The optical module according to (5), wherein

[0175] The second cover portion has a second groove disposed in a portion of the second cover portion, and

[0176] The second reflecting surface is the inner wall of the second groove.

[0177] (7) The optical module according to (5), wherein the second reflective surface is an end surface of the second cover portion.

[0178] (8) The optical module according to any one of (1) to (7), wherein

[0179] The second light receiving portion is arranged to extend elongated in one direction,

[0180] The first cover has a first reflecting surface in a portion of the first cover, the first reflecting surface being disposed obliquely with respect to a main surface of the first cover and configured to reflect the second light in a direction different from a direction of the target to propagate the second light in the same direction as the one direction, and

[0181] The second cover has, in a portion of the second cover, a second reflection surface which is provided obliquely with respect to a main surface of the second cover and is configured to reflect the second light reflected by the first reflection surface in a direction of the second light receiving portion.

[0182] (9) The optical module according to (8), wherein the second light receiving section is a single pixel having a shape elongated in one direction.

[0183] (10) The optical module according to (8), wherein the second light receiving section includes a plurality of pixels arranged to extend elongated in one direction.

[0184] (11) The optical module according to any one of (1) to (10), wherein the first cover portion and the second cover portion are integrally configured.

[0185] (12) The optical module according to any one of (1) to (11), wherein the first light receiving section and the second light receiving section are integrally configured.

[0186] (13) A distance measuring device comprising:

[0187] a light emitting portion configured to emit light;

[0188] A light receiving unit, comprising a first light receiving unit and a second light receiving unit;

[0189] a first cover portion provided on a light emitting side of the light emitting portion and configured to guide first light which is a part of the light emitted from the light emitting portion in a direction of a target and to guide second light which is another part of the light emitted from the light emitting portion in a direction different from the direction of the target;

[0190] a second cover portion provided on the light incident side of the light receiving portion and configured to guide reflected light as first light reflected by the object in the direction of the first light receiving portion and to guide second light guided from the first cover portion in the direction of the second light receiving portion; and

[0191] A processor is configured to calculate the distance to the target based on a first pixel signal output from the first light receiving portion in response to reflected light incident on the first light receiving portion, and is configured to calibrate the distance based on a second pixel signal output from the second light receiving portion in response to second light incident on the second light receiving portion.

[0192] (14) The distance measuring device according to (13), wherein the processor is configured to calculate the distance by a direct method.

[0193] (15) The distance measuring device according to (13), wherein the processor is configured to calculate the distance by an indirect method.

[0194] Reference Numbers List

[0195] 1 Distance measuring device

[0196] 2 Ranging Target

[0197] 10. Light-emitting part

[0198] 10S light emitting part substrate

[0199] 11 Luminous body

[0200] 20 Light receiving unit

[0201] 20S light receiving unit substrate

[0202] 21A First light receiving unit

[0203] 21B Second light receiving unit

[0204] 30 first cover

[0205] 30P main surface

[0206] 31, 61 first reflection surface

[0207] 32, 62 first groove

[0208] 33, 65 light diffusion film

[0209] 40 second cover

[0210] 40P main surface

[0211] 41, 63 second reflection surface

[0212] 42, 64 second groove

[0213] 43, 66 infrared filter

[0214] 50 processors

[0215] 60 Public cover

[0216] 60P main surface

[0217] S1 first pixel signal

[0218] S2 second pixel signal

[0219] 100 substrates

[0220] 101 Retainer

[0221] 101A Light-emitting opening

[0222] 101B light receiving unit opening

[0223] 102 lens holder

[0224] 103, 104 lens

[0225] This application claims the benefit of Japanese Priority Patent Application No. 2018-212133 filed in the Japan Patent Office on November 12, 2018, the entire contents of which are hereby incorporated by reference.

[0226] It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.

Claims

1. An optical module, comprising: a light emitting part configured to emit light; a light receiving part including a first light receiving part and a second light receiving part; a first cover part provided on a light emitting side of the light emitting part and configured to guide a first light, which is a part of the light emitted from the light emitting part, in a target direction and guide a second light, which is another part of the light emitted from the light emitting part, in a direction different from the target direction; and a second cover part provided on a light incident side of the light receiving part and configured to guide a reflected light of the first light reflected by the target in a direction of the first light receiving part and guide the second light guided from the first cover part in a direction of the second light receiving part; wherein, the first cover part has a first reflection surface in a part of the first cover part, the first reflection surface is inclined with respect to a main surface of the first cover part and protrudes toward the light receiving part side, and the first reflection surface is configured to reflect the second light in the direction different from the target direction.

2. The optical module according to claim 1, wherein, the first cover part has a first groove provided in the part of the first cover part, and the first reflection surface is an inner wall of the first groove.

3. The optical module according to claim 1, wherein, the first reflection surface is an end surface of the first cover part.

4. The optical module according to claim 1, wherein, the second cover part has a second reflection surface in a part of the second cover part, the second reflection surface is inclined with respect to a main surface of the second cover part and is configured to reflect the second light in a direction of the second light receiving part.

5. The optical module according to claim 4, wherein, the second cover part has a second groove provided in the part of the second cover part, and the second reflection surface is an inner wall of the second groove.

6. The optical module according to claim 4, wherein, the second reflection surface is an end surface of the second cover part.

7. The optical module according to claim 1, wherein, the second light receiving part is provided to be elongated in one direction, the first reflection surface is configured to reflect the second light in the direction different from the target direction so that the second light propagates in a direction same as the one direction, and the second cover part has a second reflection surface in a part of the second cover part, the second reflection surface is inclined with respect to a main surface of the second cover part and is configured to reflect the second light reflected by the first reflection surface in a direction of the second light receiving part.

8. The optical module according to claim 7, wherein, the second light receiving part is a single pixel having a shape elongated in the one direction.

9. The optical module according to claim 7, wherein, the second light receiving part includes a plurality of pixels arranged elongated in the one direction.

10. The optical module according to claim 1, wherein, the first cover part and the second cover part are integrally formed.

11. The optical module according to claim 1, wherein, the first light receiving portion and the second light receiving portion are integrally formed.

12. A distance measuring device, comprising: a light emitting portion configured to emit light; a light receiving portion including a first light receiving portion and a second light receiving portion; a first cover portion provided on a light emitting side of the light emitting portion and configured to guide a first light, which is a part of the light emitted from the light emitting portion, in a direction of a target and guide a second light, which is another part of the light emitted from the light emitting portion, in a direction different from the direction of the target; a second cover portion provided on a light incident side of the light receiving portion and configured to guide a reflected light of the first light reflected by the target in a direction of the first light receiving portion and guide the second light guided from the first cover portion in a direction of the second light receiving portion; and a processor configured to calculate a distance to the target based on a first pixel signal output from the first light receiving portion in response to the reflected light incident on the first light receiving portion and calibrate the distance based on a second pixel signal output from the second light receiving portion in response to the second light incident on the second light receiving portion, wherein the first cover portion has a first reflecting surface in a part of the first cover portion, the first reflecting surface is inclined with respect to a main surface of the first cover portion and protrudes toward the light receiving portion side, and the first reflecting surface is configured to reflect the second light in the direction different from the direction of the target.

13. The distance measuring device according to claim 12, wherein, the processor is configured to calculate the distance by a direct method.

14. The distance measuring device according to claim 12, wherein, the processor is configured to calculate the distance by an indirect method.

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