OPTICAL MODULE AND DISTANCE MEASURING DEVICE

Abstract

Optical module comprising: a light-emitting section (10) configured to emit light; a light-receiving section (20) comprising a first light-receiving section (21A) and a second light-receiving section (21B); a first cover part (30) provided on a light-emitting side of the light-emitting section (10) and configured to direct a first light, which is a portion of the light emitted by the light-emitting section (10), towards a target and to direct a second light, which is another portion of the light emitted by the light-emitting section (10), in a direction different from the direction of the target; and a second cover part (40) which is provided on a light-incident side of the light-receiving section (20) and is configured to direct reflected light, which is the first light reflected from the target, towards the first light-receiving section (21A) and to direct the second light directed by the first cover part (30) towards the second light-receiving section (21B), wherein the first cover part (30) has in a region of the first cover part (30) a first reflective surface (31) which is inclined with respect to a main surface (30P) of the first cover part (30) and is configured to reflect the second light in a direction different from the direction of the target, wherein the first cover part (30) either has a first recess (32) provided in the area of ​​the first cover part (30), and the first reflective surface (31) is an inner wall of the first recess (32), or the first reflective surface (31) is an end face of the first cover part (30).

Description

Technical area

[0001] The present disclosure relates to a distance measuring device that measures a distance to a target and an optical module to be used in such a distance measuring device. Background technology

[0002] For example, distance measuring devices use a passive method that does not use light and an active method that uses light. Passive methods include a multi-eye method, etc., and active methods include a TOF (time-of-flight) method, etc.

[0003] The TOF method is a method for measuring the delay time of light reflected back from a target and measuring the distance to the target based on the delay time (e.g., see PTL1). Examples include JP 2010 - 286 448 A, WO 2014 / 188 756 A1, WO 2018 / 131 514 A1, and US 2019 / 0 339 366 A1. Citation listPatent literature

[0004] PTL1: Unexamined US patent application publication number US 2018 / 0 026 058 A1. Summary of the invention

[0005] Furthermore, it is desirable to provide, in a distance measuring device, an optical path for calibrating a distance to a distance measuring object obtained from the distance measuring device more easily.

[0006] It is desired to provide a distance measuring device that enables an optical path for calibrating a distance to a distance measuring target to be provided more easily, and an optical module to be used in the distance measuring device.

[0007] This object is achieved, among other things, by an optical module and a distance measuring device according to the independent patent claims. Further embodiments are the subject of the dependent patent claims.

[0008] An optical module according to an embodiment of the present disclosure includes a light-emitting section, a light-receiving section, a first cover member, and a second cover member. The light-emitting section is configured to emit light. The light-receiving section includes a first light-receiving section and a second light-receiving section. The first cover member is provided on the light-emitting side of the light-emitting section. The first cover member is configured to guide a first light, which is a portion of the light emitted from the light-emitting section, toward a target and to guide a second light, which is another portion of the light emitted from the light-emitting section, in a direction different from the direction of the target. The second cover member is provided on the light-incident side of the light-receiving section.The second cover is configured to direct reflected light, which is the first light reflected from the target, towards the first light-receiving section and to direct the second light directed by the first cover towards the second light-receiving section.

[0009] A distance measuring device according to an embodiment of the present disclosure includes a light-emitting section, a light-receiving section, a first cover member, a second cover member, and a processor. The light-emitting section is configured to emit light. The light-receiving section includes a first light-receiving section and a second light-receiving section. The first cover member is provided on a light-emitting side of the light-emitting section. The first cover member is configured to direct a first light, which is a portion of the light emitted from the light-emitting section, toward a target and to direct a second light, which is another portion of the light emitted from the light-emitting section, in a direction different from the direction of the target. The second cover member is provided on the light-incident side of the light-receiving section.The second cover is configured to direct reflected light, which is the first light reflected from the target, towards the first light-receiving section, and to direct the second light, also directed by the first cover, towards the second light-receiving section. The processor is configured to calculate a distance to the target based on a first pixel signal output by the first light-receiving section in response to the reflected light incident on it. The processor is also configured to calibrate the distance based on a second pixel signal output by the second light-receiving section in response to the second light incident on it.

[0010] In the optical module according to one embodiment of the present disclosure, the first light, which is a portion of the light emitted by the light-emitting section, is transmitted through the first cover to reach the target, and the reflected light from the target is transmitted through the second cover to enter the first light-receiving section. On the other hand, the second light, which is another portion of the light emitted by the light-emitting section, is guided or directed by the first cover in a direction opposite to the target and is directed by the second cover to the second light-receiving section to enter the second light-receiving section.

[0011] In the distance measuring device according to an embodiment of the present disclosure, the first light, which is a portion of the light emitted from the light-emitting section, is transmitted through the first cover member to reach the target, and the reflected light from the target is transmitted through the second cover member to enter the first light-receiving section. Then, based on the first pixel signal from the first light-receiving section, the distance to the target is calculated. On the other hand, the second light, which is another portion of the light emitted from the light-emitting section, is guided by the first cover member in the direction different from the target and is guided by the second cover member to the second light-receiving section to enter the second light-receiving section. Then, based on the second pixel signal from the second light-receiving section, the distance to the target is calibrated. Short description of the drawings [ Fig. 1] Fig. 1 is a schematic diagram illustrating an exemplary configuration of a distance measuring device according to an embodiment of the present disclosure. [ Fig. 2] Fig. 2 is a perspective view of an exemplary configuration of a main part of the Fig. 1 illustrated distance measuring device. [ Fig. 3] Fig. 3 is a perspective view of an exemplary configuration of a light-emitting section and a light-receiving section of the Fig. 1 illustrated distance measuring device. [ Fig. 4] Fig. 4 is a plan view of an exemplary configuration of the light-emitting section and the light-receiving section of the Fig. 1 illustrated distance measuring device. [ Fig. 5] Fig. Figure 5 is a perspective view of an exemplary configuration of a first cover part and a second cover part as shown in Fig. 1 illustrated distance measuring device. [ Fig. 6] Fig. Figure 6 is a perspective cross-sectional view of an exemplary configuration of the in Fig. 1 illustrated distance measuring device. [ Fig. 7] Fig. 7 is an explanatory diagram showing an example of the operation of the in Fig. 1 illustrated distance measuring device illustrated. [ Fig. 8] Fig. Figure 8 is a time-lapse diagram illustrating an optical output waveform of the light-emitting section and an optical input waveform of the light-receiving section if a distance measurement is performed using a direct method through the [elements / elements] shown. Fig. 1. The distance measuring device shown is used. [ Fig. 9] Fig. Figure 9 is an explanatory diagram illustrating a discrepancy between an actual distance and a distance measured by the distance measuring device using the direct method. [ Fig. 10] Fig. 10 is a perspective view of an exemplary configuration of a main part of a distance measuring device according to a modification example 1. [ Fig. 11] Fig. 11 is a perspective view of an exemplary configuration of a recess of a first cover part of the Fig. 10 illustrated distance measuring device. [ Fig. 12] Fig. 12 is a plan view of an exemplary configuration of first light-receiving pixels and a second light-receiving pixel of the Fig. 10 illustrated distance measuring device. [ Fig. 13] Fig. 13 is a plan view of an exemplary configuration of first light-receiving pixels and second light-receiving pixels of a distance measuring device according to Modification Example 2. [ Fig. 14] Fig. 14 is a perspective view of an exemplary configuration of a main part of a distance measuring device according to Modification Example 3. [ Fig. 15] Fig. 15 is a perspective view of an exemplary configuration of a main part of a distance measuring device according to Modification Example 4. [ Fig. 16] Fig. 16 is a perspective view of an exemplary configuration of a main part of a distance measuring device according to Modification Example 5. [ Fig. 17] Fig. 17 is a perspective cross-sectional view of a configuration of the Fig. 16 illustrated distance measuring devices. [ Fig. 18] Fig. 18 is a perspective view of an exemplary configuration of a main part of a distance measuring device according to a modification example 6. [ Fig. 19] Fig. 19 is a plan view of an exemplary configuration of a light-emitting section and a light-receiving section of a distance measuring device according to Modification Example 7. [ Fig. 20] Fig. 20 is a timing chart illustrating an optical output waveform of the light-emitting section and an optical input waveform of the light-receiving section in a case where distance measurement is performed by an indirect method. [ Fig. 21] Fig. 21 is an explanatory diagram explaining a deviation between an actual distance and a distance measured using the indirect method by the distance measuring device. [ Fig. 22] Fig. 22 is a block diagram showing an example of a schematic configuration of a vehicle control system. [ Fig. 23] Fig. 23 is a diagram of assistance in explaining an example of installation positions of an outside-vehicle information detection section and an imaging section. [ Fig. 24] Fig. 24 is a plan view of an exemplary configuration of a light-receiving section of a distance measuring device according to a modification example. Modes for carrying out the invention

[0012] Embodiments of the present disclosure will be described in detail below with reference to the drawings. It should be noted that the description will be given in the following order. 1. Embodiment (an example in which first and second cover parts are provided with recesses with reflective surfaces) 2. Modification Example 1 (an example in which the reflective surface of the second cover member and a second light-receiving section are provided to extend in one direction) 3. Modification Example 2 (an example in which the second light-receiving section is provided to include a plurality of pixels) 4. Modification Example 3 (an example in which the reflective surface of the second cover member and the second reflective section are provided to extend in one direction) 5. Modification Example 4 (an example in which the reflective surface of the second cover part is provided to extend in one direction) 6. Modification Example 5 (an example in which the first and second cover parts are integrally formed) 7. Modification Example 6 (an example in which the first and second cover parts are provided with projections having reflective surfaces) 8. Modification example 7 (an example in which the position of the second light-receiving section is shifted relative to the shortest line connecting a pixel contained in a first light-receiving section and a light-emitting body for monitoring) 9. Modification Example 8 (an example of performing a distance measurement using an indirect method) 10. Example of a use for a movable body <1. Implementation>[Configuration example]

[0013] Fig. 1 illustrates an exemplary configuration of a distance measuring device (a distance measuring device 1) according to an embodiment. The distance measuring device 1 is a device that irradiates a distance measuring target 2 with light L1, detects reflected light L1R reflected from the distance measuring target 2, and measures a distance to the distance measuring target 2 based on a detection result. The distance measuring device 1 includes a light-emitting section 10, a light-receiving section 20, a first cover member 30, a second cover member 40, and a processor 50. Of the distance measuring device 1, the light-emitting section 10, the light-receiving section 20, the first cover member 30, and the second cover member 40 may be configured as an optical module.

[0014] The light-emitting section 10 includes, for example, any light-emitting body serving 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. For example, the laser may include a VCSEL (Vertical Cavity Surface Emitting LASER). The light emitted from the light-emitting section 10 is, for example, infrared light. Further, the light emitted from the light-emitting section 10 is, for example, pulsed light. Partial light (light L1) of the light emitted from the light-emitting section 10 is emitted outward through the first cover member 30 to irradiate the distance measurement target 2.

[0015] The light-receiving section 20 is configured to receive incident light and convert it into an electrical signal. The light-receiving section 20 has a sensitivity to at least the light emitted by the light-emitting section 10. The light-receiving section 20 includes a first light-receiving section 21A and a second light-receiving section 21B. The first light-receiving section 21A includes one or more pixels. The first light-receiving section 21A is configured so that the reflected light L1R emitted by the light-emitting section 10 and reflected by the distance measurement target 2 enters through the second cover member 40. The first light-receiving section 21A converts the reflected light L1R reflected by the distance measurement target 2 into a first pixel signal S1 and outputs the first pixel signal S1 to the processor 50.Furthermore, the second light-receiving section 21B of the light-receiving section 20 contains one or more pixels. Light received by the second light-receiving section 21B and a pixel signal generated by the second light-receiving section 21B are described later.

[0016] The first cover member 30 is provided on a light-emitting side of the light-emitting section 10. For example, the first cover member 30 is held by a holder or the like so as to be spaced apart from the light-emitting section 10. Alternatively, in a case where the light-emitting section 10 is a housed light-emitting section, a cap of the housing may be configured as the first cover member 30. The first cover member 30 includes a material transparent to the light emitted from the light-emitting section 10, and includes, for example, glass or plastic. The first cover member 30 has a plate-like shape as a whole. The first cover member 30 prevents dust or the like from adhering to the light-emitting section 10, which protects the light-emitting section 10 from the outside atmosphere.

[0017] In the present embodiment, the first cover member 30 is partially provided with a first reflective surface 31. In a region of the first cover member 30 where the first reflective surface 31 is not provided, a partial light of the light emitted from the light-emitting section 10 is transmitted through the first cover member 30 so as to be guided in a direction of the distance measurement target 2. The light transmitted through the first cover member 30 so as to be guided in the direction of the distance measurement target 2 corresponds to the light L1 applied to the distance measurement target 2.Furthermore, in an area of ​​the first cover part 30, where the first reflective surface 31 is provided, another partial light of the light emitted by the light-emitting section 10 is reflected by the first reflective surface 31 in such a way that it is directed in a direction different from the direction of the distance measurement target 2. The light that is reflected by the first reflective surface 31 in such a way that it is directed in a direction different from the direction of the distance measurement target 2 is in . Fig. Figure 1 illustrates light L2. In the present embodiment, the first reflective surface 31 is an inclined surface at an angle of 45° with respect to a main surface 30P of the first cover part 30. The main surface 30P of the first cover part 30 refers here to a surface of the first cover part 30 that is substantially parallel to an XY plane and, viewed from the light-emitting section 10, lies on the far side in a Z-axis direction. The light L2 reflected from the first reflective surface 31 is directed towards the second cover part 40.As described above, the first cover member 30 directs a partial light (light L1) of the light emitted from the light-emitting section 10 toward the distance measuring target 2, and directs another partial light (light L2) of the light emitted from the light-emitting section 10 toward the direction different from the direction of the distance measuring target 2.

[0018] The second cover member 40 is provided on a light incident side of the light-receiving section 20. For example, the second cover member 40 is held by a holder or the like so as to be spaced apart from the light-receiving section 20. Like the first cover member 30, the second cover member 40 includes a material transparent to the light emitted from the light-emitting section 10, such as glass or plastic. The second cover member 40 has a plate-like shape as a whole. The second cover member 40 prevents dust or the like from adhering to the light-receiving section 20, protecting the light-receiving section 20 from the outside atmosphere.

[0019] In the present embodiment, the second cover part 40 is partially provided with a second reflective surface 41. In a region of the second cover part 40 where the second reflective surface 41 is not provided, the reflected light L1R, which was reflected from the distance measuring target 2, is transmitted through the second cover part 40 in such a way that it is directed towards the first light-receiving section 21A of the light-receiving section 20. The second reflective surface 41 is an inclined surface at an angle of 45° with respect to a main surface 40P of the second cover part 40. The main surface 40P of the second cover part 40 refers here to a surface of the second cover part 40 that is substantially parallel to the XY plane and, viewed from the light-receiving section 20, lies on the far side in the Z-axis direction.The light L2 reflected by the first reflecting surface 31 to be directed toward the second cover member 40 is reflected by the second reflecting surface 41 to be directed toward the second light-receiving section 21B of the light-receiving section 20. As described above, the second cover member 40 directs the light (the reflected light L1R) reflected from the distance measurement target 2 toward the first light-receiving section 21A and directs the light (L2) directed by the first cover member 30 toward the second light-receiving section 21B.

[0020] The reflected light L1R reflected from the distance measurement target 2 enters the first light-receiving section 21A of the light-receiving section 20 to be converted into the first pixel signal S1. The first pixel signal S1 is output to the processor 50. Further, another partial light (light L2) emitted from the light-emitting section 10 and reflected by the first reflecting surface 31 of the first cover member 30 and the second reflecting surface 41 of the second cover member enters the second light-receiving section 21B of the light-receiving unit 20 to be converted into a second pixel signal S2. The second pixel signal S2 is output to the processor 50.

[0021] The processor 50 is configured to drive the light-emitting section 10 to cause each light-emitting body 11 of the light-emitting section 10 to emit light. Furthermore, the processor 50 is configured to calculate the distance between the distance measuring device 1 and the distance measurement 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 member 30 and the second cover member 40.

[0022] In the distance measuring device 1, a light diffuser, an optical filter such as a bandpass filter, a lens, or other optical component may be appropriately provided, if necessary, on an optical path taken until a partial light of the light emitted from the light-emitting section 10 is 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 component may be appropriately provided, if necessary, on an optical path taken until another partial light of the light emitted from the light-emitting section 10 enters the second light-receiving section 21B of the light-receiving section 20 through the first cover member 30 and the second cover member 40. (Detailed configuration example)

[0023] Fig. Figure 2 illustrates an exemplary configuration of a main part of the distance measuring device 1. Fig. Figure 2 illustrates the light-emitting section 10, the light-receiving section 20, the first cover part 30 and the second cover part 40 of the distance measuring device 1. Fig. 3 and Fig. Figure 4 illustrates an exemplary configuration of the light-emitting section 10 and the light-receiving section 20 of the distance measuring device 1.

[0024] 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, etc.) arranged in a matrix on the light-emitting section substrate 10S. Although four by four (four in an X-axis direction and four in a Y-axis direction), that is, sixteen, light-emitting bodies 11 are arranged in the drawing, this number is not limiting, 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, or the like. A partial light of the light emitted from the light-emitting section 10 is a light (light L1) guided toward the distance measurement target 2 described above to irradiate the distance measurement target 2.Another partial light of the light emitted from the light-emitting section 10 is a light (light L2) that enters the second light-receiving section 21B of the light-receiving section 20 through the first cover member 30 and the second cover member 40. The light L2 is also referred to as a monitoring light, and a light-emitting body that emits the light L2 is also referred to as a monitoring light-emitting body 11M. A light-emitting body 11 is shown in FIG. Fig. 2 and Fig. 3 as the monitoring light-emitting body 11M; without limitation, two or more light-emitting bodies 11 may be the monitoring light-emitting body 11M. Furthermore, light emitted by one or two or more light-emitting bodies 11 may be partially used as monitoring light.

[0025] The light-receiving section 20 is located on the X-axis side of the light-emitting section 10. The light-receiving section 20 contains a substrate 20S of the light-receiving section and the first light-receiving section 21A and the second light-receiving section 21B, which are located on the substrate 20S of the light-receiving section. The first light-receiving section 21A is located on the far side in the X-axis direction when viewed from the light-emitting section 10, and the second light-receiving section 21B is located on the near side. Pixels of the first light-receiving section 21A and the second light-receiving section 21B each receive incident light and output an electrical signal corresponding to a certain amount of the received light.The first light-receiving section 21A is a pixel array and contains, 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 note). Each pixel contains a light-receiving element, such as a PD (photodiode). The second light-receiving section 21B also contains a pixel. Although it is shown in the drawing as containing one pixel, it can contain two or more pixels. The second light-receiving section 21B contains 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. In the configuration of the light-emitting section 10 and the light-receiving section 20 shown in... Fig. 4, in the present embodiment, the second light-receiving section 21B is formed smaller than the first light-receiving section 21A in both the X-axis direction and the Y-axis direction. The second light-receiving section 21B is provided so as to be located at a position corresponding to the vicinity of the center of the first light-receiving section 21 in the Y-axis direction. The second light-receiving section 21B lies on the shortest line (dotted chain line 10C) connecting a pixel included in the first light-receiving section 21A and the light-emitting body 11M for monitoring.

[0026] Fig. 5 illustrates an exemplary configuration of the first cover part 30 and the second cover part 40 of the distance measuring device 1. The first cover part 30 has a plate-like shape and is partially provided with a first recess 32. A portion of an inner wall of the first recess 32 is the first reflective surface 31, which is an inclined surface having an angle of 45° with respect to the main surface 30P of the first cover part 30. The inner wall of the first recess 32 is in contact with the air. If the first cover part 30 includes glass, it is possible to form the first recess 32 by countersinking, blasting, or the like. If the first cover part 30 further includes plastic, it is possible to form the first recess 32 by molding.The first reflective surface 31 reflects monitoring light emitted by the light-emitting body 11M for monitoring purposes, according to a difference between the refractive index of the material forming the first cover 30 and the refractive index of air, and directs the monitoring light in a direction different from the direction of the distance measurement target 2. To increase the degree of light reflection on the first reflective surface 31, a reflective film containing a silver or other metallic film or the like can be provided on the first reflective surface 31. Alternatively, a film made of a light-blocking material can be provided on the first reflective surface 31. Alternatively, the first recess 32 can be filled with a material having a refractive index different from that of the material forming the first cover 30.Alternatively, the first recess 32 can be filled with a light-blocking material. Furthermore, the first reflective surface 31 need not necessarily be totally reflective or highly reflective. For example, the light emitted by the light-emitting body 11M for monitoring purposes and falling on the area of ​​the first recess 32 can be partially reflected to be used as monitoring light, and the remainder can be transmitted and directed towards the distance measurement target 2 to be used as light (L1) applied to the distance measurement target 2.

[0027] The second cover part 40 has a plate-like shape and is partially provided with a second recess 42. A portion of the inner wall of the second recess 42 is the second reflective surface 41, which is an inclined surface at an angle of 45° with respect to the main surface 40P of the second cover part 40. The inner wall of the second recess 42 is in contact with the air. The second recess 42 can be configured similarly to the first recess 32. The second reflective surface 41 reflects monitoring light emitted by the monitoring light-emitting body 11M and reflected by the first reflective surface 31, according to a difference between the refractive index of the material forming the second cover part 40 and the refractive index of the air, and directs the monitoring light towards the second light-receiving section 21B.To increase the light reflectance on the second reflective surface 41, for example, a reflective film containing a silver or other metal film or the like may be provided on the second reflective surface 41, a film made of a light-shielding material may be provided on the second reflective surface 41, the second recess 42 may be filled with a material having a refractive index different from that of the material constituting the second cover member 40, or the second recess 42 may be filled with a light-shielding material. Furthermore, the second reflective surface 41 does not necessarily have to be totally reflective or highly reflective.

[0028] The first cover part 30 and the second cover part 40 are aligned to provide an optical path for the monitoring light L2. The first cover part 30 and the second cover part 40 are large enough to allow easy adjustment of the optical path of the monitoring light L2.

[0029] Fig. 6 illustrates an exemplary cross-sectional structure of the distance measuring device 1. A holder 101 is arranged on a substrate 100. The holder 101 is provided with a light-emitting section opening 101A and a light-receiving section opening 101B. The light-emitting section 10, which is housed, is arranged on the substrate 100 within the light-emitting section opening 101A. The housed light-emitting section 10 is provided with the first cover part 30 as a cap of the housing. The first cover part 30 is provided with the first reflective surface 31. Further, a light-diffusing film 33 for diffusing the light emitted from the light-emitting section 10 toward the distance measuring target 2 is formed on the first cover part 30.

[0030] The light-receiving section 20 is further arranged on the substrate 100 within the opening 101B of the light-receiving section. The second cover member 40 is provided on the light-incident side of the light-receiving section 20. The second cover member 40 is provided with the second reflective surface 41. Furthermore, the second cover member 40 is provided with an infrared filter 43 for transmitting infrared light, which is light from the light-emitting section 10. Furthermore, a lens holder 102 is provided within the opening 101B of the light-receiving section. The lens holder 102 holds lenses 103 and 104. Furthermore, the substrate 100 may be provided with the processor 50, which is coupled to the light-emitting section 10 and the light-receiving section 20. Alternatively, the light-emitting section 10 and the light-receiving section 20 can be coupled to the processor 50, which is provided separately via the substrate 100.In addition to the above, further optical components can be appropriately provided in aperture 101A of the light-emitting section and aperture 101B of the light-receiving section.

[0031] Here, the light-emitting section 10 corresponds to a specific example of a "light-emitting section" in the present disclosure. The light-receiving section 20 corresponds to a specific example of a "light-receiving section" in the present disclosure. The first cover part 30 corresponds to a specific example of a "first cover part" in the present disclosure. The second cover part 40 corresponds to a specific example of a "second cover part" in the present disclosure. The processor 50 corresponds to a specific example of a "processor" in the present disclosure. [Operation and working methods]

[0032] Next, the operation and operation of the distance measuring device of the present embodiment will be described. (Overview of a general operation)

[0033] First, with reference to Fig. 1 describes an overview of the general operation of the distance measuring device. Controlled by the processor 50, the light-emitting section 10 emits light. A partial light (light L1) of the light emitted by the light-emitting section 10 is transmitted through the first cover member 30 and guided toward the distance measuring target 2 to irradiate 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 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 measurement target 2 based on the time required for the light emitted by the light-emitting section 10 to be reflected from the distance measurement target 2 to enter the light-receiving section 20. Simultaneously, another partial light (monitoring light L2) of the light emitted by the light-emitting section 10 is reflected by the first reflective surface 31 of the first cover 30 to be directed towards the second cover 40, and is reflected by the second reflective surface 41 of the second cover 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.Processor 50 first generates a correction value table for measured distances based on the second pixel signal S2. Processor 50 then 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 with the obtained correction value. (Detailed operation)

[0034] Fig. 7 illustrates an exemplary operation of the distance measuring device 1. By being controlled by the processor 50, each light-emitting body 11 of the light-emitting section 10 emits light toward the first cover part 30.

[0035] A partial light (light L1) falling on an area of ​​the first cover part 30 where the first recess 32 is not provided is transmitted through the first cover part 30 and directed towards 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.

[0036] On the other side, another partial light (monitoring light L2) falling on an area of ​​the first cover part 30, where the first recess 32 is provided, is reflected by the first reflective surface 31 provided in the first recess 32 to be directed towards the second cover part 40. The monitoring light L2 directed towards the second cover part 40 is reflected by the second reflective surface 41 provided in the second recess 42 to enter the second light-receiving section 21B of the light-receiving section 20.

[0037] The first light-receiving section 21A receives the reflected light L1R and outputs the first pixel signal S1 to the processor 50. Each of the n × m pixels arranged in a matrix within the first light-receiving section 21A outputs the first pixel signal S1. Furthermore, the second light-receiving section 21B receives the monitoring light L2 and outputs the second pixel signal S2 to the processor 50.

[0038] For measuring the distance to distance measurement target 2 by the in Fig. In the distance measuring device 1 illustrated in Figure 1, a direct method and an indirect method can be used, for example; the present embodiment is described using the direct method. Based on the first pixel signal S1, the processor 50 measures the time required for the light emitted by the light-emitting section 10 to be reflected from the distance measuring target 2 to enter the light-receiving section 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 section 21A, the measurement of the time required for the light emitted by the light-emitting section 10 to be reflected from the distance measuring target 2 to reach the light-receiving section 20 and the calculation of the distance to the distance measuring target 2 based on the obtained time are performed.Furthermore, the processor 50 calibrates the distance to the distance measurement target 2 based on the second pixel signal S2. Details of the calibration will be described later. The calibration of the distance to the distance measurement target 2 based on the second pixel signal S2 is performed for each of the n × m pixels of the first light-receiving section 21A.

[0039] The processor 50 measures the time required for the light emitted by the light-emitting section 10 to be reflected from the distance measuring target 2 to enter the light-receiving section 20, based on the first pixel signal S1 output by the first light-receiving section 21A of the light-receiving section 20 using the direct method, and calculates the distance between the distance measuring device 1 and the distance measuring target 2 on the basis of the obtained time in the following manner.

[0040] Fig. Fig. 8 illustrates an exemplary operation in a case where a distance measurement is performed by the direct method by the distance measuring device 1; (A) illustrates an optical output waveform (an emitted pulse) of the light-emitting section 10, and (B) illustrates an optical input waveform (an incident pulse) of the light-receiving section. The optical output waveform of the light-emitting section 10 ((A) of Fig. 8) is an output waveform of light immediately after it is emitted by the light-emitting section 10, and has, for example, a pulse shape.

[0041] The optical input waveform of the light-receiving section 20 ((B) of Fig. 8) is a waveform of light when the light (the reflected light L1R) emitted from the light-emitting section 10 and reflected from the distance measuring target 2 reaches the first light-receiving section 21A of the light-receiving section 20. The optical input waveform of the light-receiving section 20 has a pulse shape which is similar to that shown in (A) of Fig. 8 is delayed by a delay time DL. The delay time DL corresponds to the time required for the light emitted by the light-emitting section 10 to be reflected by the distance measurement target 2 and received by the light-receiving section 20. By obtaining the delay time DL, it is therefore possible to calculate the distance to the distance measurement target 2.

[0042] During the calculation of the distance to the distance measurement target 2 described above, a deviation may occur between the calculated distance (measured distance) and the actual distance (actual distance). This deviation occurs due to, for example, a circuit delay or the like in the light-emitting section 10, the light-receiving section 20, and the processor 50.

[0043] Fig. Fig. 9 illustrates an example of the deviation between the actual distance and the distance measured by the distance measuring device 1 in a case where the present technology is used for the direct method. Fig. In Figure 9, the horizontal axis represents an actual distance d1, and the vertical axis represents a 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 with a slope "a1" (a1 = 1) and an intersection point "0". In practice, however, the relationship between the actual distance d1 and the measured distance d2 is often represented by a straight line LN2. This straight line LN2 has a slope "a2" and an intersection point "b". That is, the slope and intersection point of the straight line LN2 differ from the slope and intersection point of the straight line LN1.

[0044] In the present embodiment, the measured distance is calibrated as follows. The processor 50 calibrates the measured distance based on the second pixel signal S2 output from the second light-receiving section 21B in response to the other partial light (monitoring light L2) incident on the second light-receiving section 21B. Specifically, the processor 50 performs a correction value table generation operation and a normal operation (distance measurement). The correction value table generation operation is performed, for example, before the normal operation. The correction value table generation operation can be performed at any time as long as the normal operation is not performed. In the correction value table generation operation, the processor 50 generates a correction value table based on the second pixel signal S2.Specifically, while performing control to change an emission timing of the monitor light L2 to different timings, the processor 50 detects a light reception timing at which the second light-receiving section 21B receives the monitor light L2, and obtains the measured distance corresponding to each emission timing based on the second pixel signal S2. On the other hand, the processor 50 multiplies an amount (time) of change in the emission timing known to the processor 50 by the speed of light to obtain the actual distance. The processor 50 calculates a difference between the measured distance obtained based on the second pixel signal S2 and the actual distance obtained from the amount (time) of change in the emission timing. The calculated difference value is a correction value corresponding to the measured distance obtained based on the second pixel signal S2.The processor 50 generates the correction value table by obtaining the correction value for each emission time point. In normal operation (distance measurement), based on the first pixel signal S1, the processor 50 measures the time required for the light emitted from the light-emitting section 10 to be reflected by the distance measurement target 2 to enter the light-receiving section 20, and calculates the distance to the distance measurement target 2 from the obtained time. For each of the n × m pixels of the first light-receiving section 21A, the measurement of the time required for the light emitted from the light-emitting section 10 to be reflected by the distance measurement target 2 to enter the light-receiving section 20 and the calculation of the measured distance to the distance measurement target 2 based on the obtained time are performed.Further, the processor 50 refers to the correction value table previously generated based on the second pixel signal S2 to obtain the correction value corresponding to the measured distance obtained from the first pixel signal S1, and calibrates the measured distance to the distance measurement target 2 with the obtained correction value. The calibration of the distance to the distance measurement target 2 is performed for each of the n × m pixels of the first light-receiving section 21A.

[0045] In the distance measuring device 1 as described above, a partial light from the light emitted by the light-emitting section 10 is applied to the distance measuring target 2 in the first cover 30, with the reflected light L1R entering the first light-receiving section 21A of the light-receiving section 20. Another partial light enters the second light-receiving section 21B of the light-receiving section 20 through the first cover 30 and the second cover 40. This allows the optical path of the monitoring light L2 to be provided. The correction value table used for distance calibration can be generated from the second pixel signal S2, which is output by the second light-receiving section 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, thus increasing the accuracy of the distance to the distance measuring target 2.This means that it is possible to calibrate the distance to the distance measurement target 2 based on the second pixel signal S2 output by the second light-receiving section 21B.

[0046] Furthermore, in the distance measuring device 1, the first cover part 30 having the first reflective surface 31 is arranged on the light-emitting side of the light-emitting section 10, and the second cover part 40 having the second reflective surface 41 is arranged on the light-incident side of the light-receiving section 20, which makes it easy to provide the optical path of the monitoring light L2. Furthermore, the first cover part 30 and the second cover part 40 are large enough for adjustment of the optical path of the monitoring light L2, which makes it easy to adjust the optical path of the monitoring light L2. [Effects]

[0047] In the present embodiment as described above, the first cover part is provided with the first reflective surface and the second cover part with the second reflective surface, which makes it easy to provide the optical path of the monitoring light for the detection of the second pixel signal. Therefore, it is possible to easily calibrate the distance to the distance measurement target based on the second pixel signal. <2. Modification example 1>

[0048] In the above embodiment, the second light-receiving section 21B has a size such that it is located at a position corresponding to the vicinity of the center of the first light-receiving section 21A in the Y-axis direction, but is not limited thereto. Alternatively, for example, the second light-receiving section 21B may extend elongatedly in a direction D (a direction parallel to the Y-axis direction). Further, the second reflective surface 41 of the second cover member 40 may also extend in the one direction D so as to correspond to the second light-receiving section 21B extending in the one direction D.

[0049] Fig. 10 illustrates an exemplary configuration of a main part of a distance measuring device 1A according to Modification Example 1. In this example, the second recess 42 of the second cover part 40 extends elongately in the one direction D, and the second reflective surface 41 is provided to extend elongately in the one direction D. Further, the second light-receiving section 21B is provided to extend elongately in the one direction D1. The one direction D in which the second reflective surface 41 of the second cover part 40 and the second light-receiving section 21B extend is, for example, an extension direction (Y-axis direction) of one side of the first light-receiving section 21A on the light-emitting section 10 side.

[0050] Fig. Figure 11 illustrates, in an enlarged view, an exemplary configuration of the first recess 32 of the first cover part 30 of the distance measuring device 1A. The first reflective surface 31 of the first recess 32, which is provided in a region of the first cover part 30, is inclined with respect to the main surface 30P of the first cover part 30 and is furthermore a curved surface that is convex towards the side of the light-receiving section 20. As shown in Fig. 10, the first reflecting surface 31, which is a curved surface, reflects the monitoring light L2 in the direction different from the direction of the distance measuring target 2 so as to spread the monitoring light L2 in the same direction as the one direction D.

[0051] Fig. Figure 12 illustrates an exemplary configuration of the first light-receiving section 21A and the second light-receiving section 21B of the distance measuring device 1A. In the present modification example, the second light-receiving section 21B is a single pixel with a shape that extends elongately in one direction D. The first light-receiving section 21A is the one shown in Figure 12. Fig. 4 illustrated first light-receiving section 21A similarly.

[0052] In the distance measuring device 1A of the present modification example, the monitoring light L2 of the light emitted by the light-emitting section 10 is reflected by the first reflective surface 31 of the first cover part 30 and directed towards the second cover part 40 such that it is spread in the same direction as one direction D. The monitoring light L2, spread in the same direction as one direction D, is reflected by the second reflective surface 41, which extends longitudinally in one direction D, and directed towards the second light-receiving section 21B, which also extends longitudinally in one direction D, in order to enter. Except for the above point, it is similar to the embodiment described above.

[0053] In the distance measuring device 1A of the present modification example, the monitoring light L2 is spread in the same direction as the one direction D and is reflected by the second reflecting surface 41 to enter the second light-receiving section 21B elongated in the one direction D. This configuration therefore allows the monitoring light L2 to easily enter the second light-receiving section 21B. Thus, an allowable range of alignment in the one direction D between the first cover member 30 and the second cover member 40 is expanded. Further, the allowable range of alignment in the one direction D between the second cover member 40 and the light-receiving section 20 (second light-receiving section 21B) is expanded. This makes it possible to easily adjust the optical path of the monitoring light L2. <3. Modification Example 2>

[0054] In Modification Example 1 described above, the second light-receiving section 21B is configured to be 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.

[0055] Fig. 13 illustrates an exemplary configuration of the first light-receiving section 21A and the second light-receiving section 21B of a distance measuring device 1B according to a modification example 2. The second light-receiving section 21B includes a plurality of pixels (pixels B1, B2, ..., Bn) arranged elongated in the one direction D. Although a plurality of pixels are arranged in a line in Fig. 13, there may be a plurality of lines. In the present modification example, each of the plurality of pixels (pixels B1, B2, ..., Bn) may have the same structure as each of the n × m pixels (pixels A11 to Anm) of the first light-receiving section 21A. Except for the above point, it is similar to Modification Example 1 described above.

[0056] In the distance measuring device 1B of the present modification example, the monitoring light L2 is spread in the same direction as the one direction D and is reflected by the second reflecting surface 41 to enter the second light-receiving section 21B elongated in the one direction D. This configuration therefore allows the monitoring light L2 to easily enter the second light-receiving section 21B. Thus, an allowable range of alignment in the one direction D between the first cover member 30 and the second cover member 40 is expanded. Moreover, the allowable range of alignment in the one direction D between the second cover member 40 and the light-receiving section 20 (second light-receiving section 21B) is expanded. This makes it possible to easily adjust the optical path of the monitoring light L2. <4. Modification example 3>

[0057] In the modification example 1 described above, the second recess 42 in the second cover part 40 extends elongately in one direction D, and the second reflective surface 41 also extends elongately in one direction D; however, this example is not limiting. Alternatively, for example, an end face of the second cover part 40 could be a second reflective surface 44.

[0058] Fig. Figure 14 illustrates an exemplary configuration of a main part of a distance measuring device 1C according to Modification Example 3. In this example, the end face of the second cover part 40 on the side of the light-emitting section 10 is an inclined surface at an angle of 45° with respect to the main surface 40P of the second cover part 40, and the inclined surface is the second reflective surface 44. The second reflective surface 44 is designed to extend longitudinally in one direction D. Furthermore, the second light-receiving section 21B is designed to extend longitudinally in one direction D. Except that the end face of the second cover part 40 described above is the inclined surface at an angle of 45° with respect to the main surface 40P of the second cover part 40, it is similar to Modification Example 1 described above.

[0059] In the distance measuring device 1C of the present modification example, a surface, which is to be the second reflective surface 44, is provided on the end face of the second cover part 40. Machining the end face of the second cover part 40 into the inclined surface at an angle of 45° with respect to the main surface 40P of the second cover part 40 is simpler than forming the second recess as in modification example 1.

[0060] Furthermore, the first reflective surface can similarly be provided on an end face of the first cover part 30. That is, the end face of the first cover part 30 on the side of the light-receiving section 20 can be an inclined surface at an angle of 45° with respect to the main surface 30P of the first cover part 30, and the inclined surface can be configured to be the first reflective surface. In this case, of the light emitted by the light-emitting section 10, the light entering the end face of the first cover part 30 serves as the monitoring light L2. <5. Modification Example 4>

[0061] In Modification Example 3 described above, the second light-receiving section 21B extends elongatedly in the one direction D, but is not limited thereto. Alternatively, for example, the second light-receiving section 21B does not need to extend elongatedly in the one direction and may have a size such that it is located at a position corresponding to the vicinity of the center of the first light-receiving section 21 in the Y-axis direction.

[0062] Fig. 15 illustrates an exemplary configuration of a main part of a distance measuring device 1D according to Modification Example 4. In this example, the end surface of the second cover part 40 is the second reflective surface 44 extending elongately in the one direction D, and the second reflective surface 44 is provided to extend elongately in the one direction D. Further, the second light-receiving section 21B does not extend elongately in the one direction D and is provided to be located at a position corresponding to the vicinity of the center of the first light-receiving section 21 in the Y-axis direction. The one direction D in which the second reflective surface 44 extends is, for example, an extension direction (Y-axis direction) of one side of the first light-receiving section 21A on the light-emitting section 10 side.

[0063] In the distance measuring device 1D of the present modification 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 member 30 so as to be directed toward the second cover member 40. The monitoring light L2 is reflected by the second reflecting surface 44 and directed toward the second light-receiving section 21B to enter. The first reflecting surface 31 can reflect the monitoring light L2 so as to be spread in the one direction D, or can reflect the monitoring light L2 so as not to be spread. If the first reflecting surface 31 spreads the monitoring light L2 in the one direction D, only a portion of the monitoring light L2 spread in the one direction enters the second light-receiving section 21B.In this case, the light entering the second light-receiving section 21B hardly fluctuates, even if the optical path of the monitoring light L2 is shifted in one direction D. This expands the permissible range of alignment in one direction D between the second cover part 40 and the light-receiving section 20 (second light-receiving section 21B). This makes it possible to easily adjust the optical path of the monitoring light L2. If the first reflective surface 31 does not spread the monitoring light L2 in one direction D, this configuration differs from the one in [reference missing]. Fig. The configuration illustrated in Figure 2 is modified by the fact that the second reflective surface 44 is provided on the end face of the second cover part 40 instead of in the second recess 42. This is advantageous because the end face of the second cover part 40 is easier to machine than the second recess 42. <6. Modification Example 5>

[0064] In the above embodiment, the first cover part 30 and the second cover part 40 are separate components; however, this example is not limiting. Alternatively, for example, the first cover part 30 and the second cover part 40 may be integrally formed.

[0065] Fig. 16 illustrates an exemplary configuration of a main part of a distance measuring device 1E according to Modification Example 5. A common cover member 60, into which the first cover member 30 and the second cover member 40 have been integrated, is provided on the light emission side of the light-emitting section 10 and the light incidence side of the light-receiving section 20. For example, the common cover member 60 is held by a holder or the like so as to be spaced apart from the light-emitting section 10 and the light-receiving section 20. The common cover member 60 includes a material transparent to the light emitted from the light-emitting section 10, and includes, for example, glass or plastic. The common cover member 60 has a plate-like shape as a whole.The common cover part 60 prevents dust or the like from adhering to the light-emitting section 10 and the light-receiving section 20, thus protecting the light-emitting section 10 and the light-receiving section 20 from the external atmosphere.

[0066] In the present modification example, a first reflective surface 61 is provided in a region of the common cover member 60 on the light-emitting section 10 side. The first reflective surface 61 is provided on an inner wall of a first recess 62 provided in a region of the common cover member 60 on the light-emitting section 10 side. The first reflective surface 61 is an inclined surface having an angle of 45° with respect to a main surface 60P of the common cover member 60. Further, a second reflective surface 63 is provided in a region of the common cover member 60 on the light-receiving section 20 side. The second reflective surface 63 is provided on an inner wall of a second recess 64 provided in a region of the common cover member 60 on the light-receiving section 20 side.The second reflecting surface 63 is an inclined surface having an angle of 45° with respect to the main surface 60P of the common cover part 60.

[0067] As in Fig. 1, a partial light of the light emitted from the light-emitting section 10 is transmitted through the common cover member 60 to be directed toward the distance measuring target 2, and is reflected by the distance measuring target 2 and again transmitted through the common cover member 60 to enter the first light-receiving section 21A. Further, as shown in Fig. 1, light L2, another partial light of the light emitted from the light-emitting section 10, is reflected by the first reflecting surface 61 so as to be directed toward 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 another partial light of the light emitted from the light-emitting section 10 can take an optical path in which it is reflected by the first reflecting surface 61 to be directed toward the second reflecting surface 63, and 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.

[0068] Fig. Figure 17 illustrates an exemplary configuration of the distance measuring device 1E. The holder 101 is arranged on the substrate 100. The common cover 60 is provided on the light-emitting side of the light-emitting section 10 and the light-incidence side of the light-receiving section 20. The common cover 60 is held by the holder 101. In the common cover 60, an area that overlaps with the light-emitting section 10 is partially provided with the first reflective surface 61, and an area that overlaps with the second light-receiving section 21B of the light-receiving section 20 is partially provided with the second reflective surface 63. In a region of the common cover part 60 overlapping with the light-emitting section 10, a light-diffusing film 65 is formed for diffusing the light emitted from the light-emitting section 10 in the direction of the distance measuring target 2.In an area of ​​the common cover part 60, which overlaps with the light-receiving section 20, an infrared filter 66 is provided for the transmission of infrared light, which is light from the light-emitting section 10.

[0069] In the distance measuring device 1E of the present modification example, the common cover part 60 is provided, and the common cover part 60 has a configuration in which the first cover part and the second cover part are integrated. Therefore, the relative position between the first reflective surface 61 and the second reflective surface 63 is already determined. It is possible to provide the optical path of the monitoring light (light L2) simply by arranging the single common cover part 60 on the light-emitting side of the light-emitting section 10 and the light-incident side of the light-receiving section 20.It is possible to align the first reflective surface 61 and the second reflective surface 63 with respect to the light-emitting section 10 and the light-receiving section 20 simply by aligning the common cover part 60 and the light-receiving section 20 (second light-receiving section 21B), which makes it easy to adjust the optical path of the monitoring light L2. <7. Modification 6>

[0070] In the embodiment above, a region of the inner wall of the first recess 32 is designated as the first reflective surface 31, and a region of the inner wall of the second recess 42 is designated as the second reflective surface 41; however, this example is not limited. Alternatively, for example, a region of the first cover part 30 may be provided with a first protrusion whose surface acts as the first reflective surface, and a region of the second cover part 40 may be provided with a second protrusion whose surface acts as the second reflective surface.

[0071] Fig. 18 illustrates an exemplary configuration of a main part of a distance measuring device 1F according to a modification example 6. In this example, the first cover part 30 is partially provided with a first protrusion 35, and a portion of a surface of the first protrusion 35 is a first reflective surface 34. Further, the second cover part 40 is partially provided with a second protrusion 46, and a portion of a surface of the second protrusion 46 is a second reflective surface 45.

[0072] As in Fig. 1, a partial light of the light emitted from the light-emitting section 10 is transmitted through the first cover member 30 to be directed toward the distance measurement target 2, and is reflected by the distance measurement target 2 and transmitted through the second cover member 40 to enter the first light-receiving section 21A. Further, another partial light of the light emitted from the light-emitting section 10 is reflected by the first reflective surface 34 provided on the surface of the first protrusion 35 to be directed toward the second reflective surface 45, which is a direction different from the direction of the distance measurement target 2, and is reflected by the second reflective surface 45, which is the surface of the second protrusion 46, to enter the second light-receiving section 21B.

[0073] In the distance measuring device 1F of the present modification example, a protrusion with a reflective surface is provided on both the first cover part 30 and the second cover part 40. This can preferably be done if it is easy to provide a protruding shape on the surface of the cover part, such as by molding with plastic. <8. Modification example 7>

[0074] In the above embodiment, the second light-receiving section 21B is located on the shortest line connecting a pixel included in the first light-receiving section 21A and the light-emitting body 11M for monitoring, but this is not limited to this. Alternatively, for example, the second light-receiving section 21B may be provided at a position shifted from the shortest line connecting the pixel included in the first light-receiving section 21A and the light-emitting body 11M for monitoring.

[0075] Fig. 19 illustrates an exemplary configuration of the light-emitting section and the light-receiving section of a distance measuring device 1G according to Modification Example 7. The second light-receiving section 21B is provided at a position shifted from the shortest line connecting the pixel included in the first light-receiving section 21A and the light-emitting body 11M for monitoring. The shortest line connecting the pixel included in the first light-receiving section 21A and the light-emitting body 11M for monitoring is indicated by the one-dot chain line 10C, and the second light-receiving section 21B is provided at a position shifted from the one-dot chain line 10C.In the present modification example, the first reflective surface 31 is configured with an angle such that it reflects the monitoring light L2 towards the second reflective surface 41. Furthermore, the second reflective surface 41 is configured such that its angle is configured to reflect the light incident on the first reflective surface 31 towards the second light-receiving section 21B. Except for the above point, it is similar to the embodiment described above.

[0076] The second light-receiving section 21B does not necessarily have to lie on the shortest line connecting the pixel contained in the first light-receiving section 21A and the light-emitting body 11M for monitoring. <9. Modification Example 8>

[0077] The above embodiment was described as an example in which the distance to the distance measurement target 2 is measured by the distance measuring device 1 using the direct method; however, this example is not limiting. Alternatively, for example, this distance may be measured using the indirect method. An example in which this distance is measured using the indirect method is described below.

[0078] Fig. Fig. 20 illustrates an exemplary operation in a case where a distance measurement is performed by the distance measuring device 1 using the indirect method; (A) illustrates the optical output waveform (the emitted pulse) of the light-emitting section 10, and (B) and (C) illustrate the optical input waveform (the incident pulse) of the light-receiving section. In this example, the optical output waveform of the light-emitting section 10 ((A) of Fig. 20) for example, a pulse waveform with a duty cycle of 50%.

[0079] The optical input waveform of the light-receiving section 20 ((B) and (C) of Fig. 20) has a momentum shape which, in relation to that in (A) of Fig. 20 is delayed by a predetermined time. The delay time of the pulse corresponds to the time required for the light emitted by the light-emitting section 10 and reflected by the distance measurement target 2 (the reflected light L1R) to reach the first light-receiving section 21A of the light-receiving section 20. Therefore, it is possible to calculate the distance to the distance measurement target 2 based on the delay time.

[0080] In the indirect method, a pixel of the light-receiving section 21A accumulates a signal charge Q1 in any period in a period T1 in which the light-emitting section 10 emits light, accumulates a signal charge Q2 in any period in a period T2 in which the light-emitting section 10 does not emit light, and obtains a charge ratio between the signal charge Q1 and the signal charge Q2. In the examples of (B) and (C) of Fig. 20, the pixel of the first light-receiving section 21A accumulates the signal charge Q1 by detecting the incident pulse in a period TA of the period T1, and accumulates the signal charge Q1 by detecting the incident pulse in a period TB of the period T2. In the example of (B) of Fig. 20 The charge ratio of the signal charge Q1 to the signal charge Q2 is approximately 3:1, and in the example of (C) of Fig. 20, the charge ratio of the signal charge Q1 to the signal charge Q2 is approximately 1:1. Thus, the charge ratio of the signal charge Q1 to the signal charge Q2 varies depending on the delay time of the incident pulse. By obtaining the charge ratio, it is therefore possible to obtain the delay time with high accuracy in units of, for example, picoseconds to nanoseconds. If the delay time is converted into the distance to the distance measurement target 2, it is possible to obtain the distance to the distance measurement target 2 with a resolution of 0.3 mm to 30 cm if the delay time is measured on the order of picoseconds to nanoseconds, for example.It is particularly worth mentioning that the period in which the signal charge Q1 is accumulated in the period T1 in which the light-emitting section 10 emits light, and the period in which the signal charge Q2 is accumulated in the period T2 in which the light-emitting section 10 does not emit light, can be changed as needed.

[0081] When calculating the distance to the distance measurement target 2 described above, there may be a deviation between the calculated distance (measured distance) and the actual distance (actual distance). This is due to, for example, a circuit delay in the light-emitting section 10, the light-receiving section 20, and the processor 50, a circuit configuration of the light-receiving section 20, the shape of the emitted pulse, and the like.

[0082] Fig. Fig. 21 illustrates an example of the deviation between the actual distance and the distance measured by the distance measuring device 1 in a case where the present technology is used for the indirect method. In an 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 with a slope "a1" (a1 = 1) and an intercept point "0". In practice, however, the relationship between the actual distance d1 and the measured distance d2 is often indicated by a curve LN4. This curve LN4 has a waviness component c. A straight line LN5 obtained by removing the waviness component c from this curve LN4 has a slope "a2" and an intercept point "b".That is, the slope and intersection point of the straight line LN5 are different from the slope and intersection point of the straight line LN3.

[0083] In the present embodiment, the measured distance is calibrated as follows. The processor 50 calibrates the measured distance based on the second pixel signal S2 output from the pixel of the second light-receiving section 21B in response to another partial light (monitor light L2) incident on the second light-receiving section 21B. Specifically, the processor 50 performs a correction value table generation operation and the normal operation (distance measurement) in a manner similar to that of the operation in the direct method described above. In the correction value table generation operation, the processor 50 generates the correction value table by detecting a light reception timing at which the second light-receiving section 21B receives the monitor light L2 while performing control to change an emission timing of the monitor light L2 to various timings.In normal operation (distance measurement), 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 the correction value, and calibrates the measured distance to the distance measurement target 2.

[0084] As described above, the present technology can also be used for the indirect method. It is possible to accurately measure the time required for the light emitted by the light-emitting section 10 to be reflected by the distance measurement target 2 and received by the light-receiving section 20, and the distance to the distance measurement target 2, which is derived from this time. Furthermore, it is also possible to calibrate the distance to the distance measurement target 2 obtained using the indirect method based on the second pixel signal S2 output by the second light-receiving section 21B.

[0085] The above embodiment and modification examples 1 to 8 can be combined as necessary. <10. Example of an application for a moving body>

[0086] The technology (the present technology) according to the present disclosure can be used for a variety of products. For example, the technology according to the present disclosure can be implemented as a device mounted on any type of movable body, such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an aircraft, a drone, a ship, and a robot.

[0087] Fig. 22 is a block diagram illustrating 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 an embodiment of the present disclosure can be applied.

[0088] The vehicle control system 12000 comprises a multitude of electronic control units interconnected via a communication network 12001. In the Fig. 22, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside-vehicle information detection unit 12030, an inside-vehicle information detection unit 12040, and an integrated control unit 12050. In addition, as a functional configuration of the integrated control unit 12050, a microcomputer 12051, a sound / image output section 12052, and an interface (I / F) 12053 of the vehicle-mounted network are illustrated.

[0089] The drive system control unit 12010 controls the operation of devices related to the drive system of the vehicle according to various types of programs. For example, the drive system control unit 12010 serves as a control device for a driving force generating device for generating a driving force of the vehicle, such as an internal combustion engine, a drive motor, or the like, a driving force transmitting mechanism for transmitting the driving force to wheels, a steering mechanism for adjusting the steering angle of the vehicle, a braking device for generating the braking force of the vehicle, and the like.

[0090] The body system control unit 12020 controls the operation of various types of devices provided on a vehicle body according to various types of programs. For example, the body system control unit 12020 serves as a control device for a keyless entry system, a smart key system, an automatic window device, or various types of lights such as a headlight, a taillight, a brake light, a turn signal, a fog light, or the like. In this case, radio waves transmitted from a mobile device as an alternative to a key or signals from various types of switches can be input to the body system control unit 12020.The body system control unit 12020 receives these input radio waves or signals and controls a door locking device, the automatic window device, the lights or the like of the vehicle.

[0091] The vehicle-external information detection unit 12030 detects information about the external environment of the vehicle including the vehicle control system 12000. For example, the vehicle-external information detection unit 12030 is connected to an imaging section 12031. The vehicle-external information detection unit 12030 causes the imaging section 12031 to capture an image of the vehicle's external environment and receives the captured image. The vehicle-external information detection unit 12030 can perform processing for detecting an object such as a person, a car, an obstacle, a traffic sign, a sign on a road surface, or the like, or processing for detecting a distance thereto based on the received image.

[0092] The imaging section 12031 is an optical sensor that receives light and outputs an electrical signal according to the amount of light received. The imaging section 12031 can also output the electrical signal as an image or can output the electrical signal as information about a measured distance. Furthermore, the light received by the imaging section 12031 can be visible light or invisible light such as infrared rays or the like.

[0093] The in-vehicle information detection unit 12040 detects information about the interior of the vehicle. The in-vehicle information detection unit 12040 is connected, for example, to a driver condition detection section 12041 that detects the condition of a driver. The driver condition detection section 12041 includes, for example, a camera that records the driver. The in-vehicle information detection unit 12040 can calculate a driver fatigue level or a driver concentration level, or can determine whether the driver is dozing, based on detection information input from the driver condition detection section 12041.

[0094] The microcomputer 12051 may calculate a control target value for the driving force generating device, the steering mechanism, or the braking device based on the information about the interior or exterior of the vehicle obtained by the outside-vehicle information detecting unit 12030 or the inside-vehicle information detecting unit 12040, and may output a control command to the drive system control unit 12010.For example, the microcomputer 12051 may perform cooperative control intended to realize functions of an advanced driver assistance system (ADAS) whose functions include collision avoidance or impact mitigation for the vehicle, following travel based on a following distance, constant speed travel, collision warning of the vehicle, lane deviation warning of the vehicle, or the like.

[0095] In addition, the microcomputer 12051 can perform cooperative control intended for automatic driving, which makes the vehicle drive autonomously without depending on driver intervention or the like, by controlling the driving force generating device, the steering mechanism, the braking device, or the like based on the information about the external environment or the interior of the vehicle, which information is obtained by the outside-vehicle information detecting unit 12030 or the inside-vehicle information detecting unit 12040.

[0096] The microcomputer 12051 can also output a control command to the body system control unit 12020 based on the information about the external environment of the vehicle obtained by the external vehicle information detection unit 12030. For example, the microcomputer 12051 can execute cooperative control intended to prevent glare by controlling the headlight to switch from high beam to low beam according to the position of a preceding vehicle or an oncoming vehicle detected by the external vehicle information detection unit 12030.

[0097] The sound / image output section 12052 transmits an output signal of a sound and / or an image to an output device that can optically or acoustically convey information to an occupant of the vehicle or the external environment of the vehicle. In the example of Fig. 22, a speaker 12061, a display section 12062, and an instrument panel 12063 are indicated as the output device. The display section 12062 may include, for example, an in-vehicle display and / or a head-up display.

[0098] Fig. 23 is a diagram illustrating an example of an installation position of the imaging section 12031.

[0099] In Fig. 23, imaging section 12031 includes imaging sections 12101, 12102, 12103, 12104 and 12105.

[0100] The imaging sections 12101, 12102, 12103, 12104, and 12105 are arranged at positions on, for example, a front end, side mirrors, a rear bumper, and a rear door of the vehicle 12100, as well as a position on an upper part of a windshield inside the vehicle. The imaging section 12101 provided at the front end and the imaging section 12105 provided at the upper part of the windshield inside the vehicle predominantly obtain an image from the front of the vehicle 12100. The imaging sections 12102 and 12103 provided at the side mirrors predominantly obtain an image from the sides of the vehicle 12100. The imaging section 12104 provided at the rear bumper or rear door predominantly obtains an image from the rear of the vehicle 12100.The imaging section 12105 provided at the upper part of the windshield inside is mainly used to detect a preceding vehicle, a pedestrian, an obstacle, a traffic light, a traffic sign, a lane or the like.

[0101] Furthermore, Fig. 23 illustrates an example of photographing ranges of the imaging sections 12101 to 12104. An imaging range 12111 represents the imaging range of the imaging section 12101 provided at the front end. Imaging ranges 12112 and 12113 represent the imaging ranges of the imaging sections 12102 and 12103 provided at the side mirrors, respectively. An imaging range 12114 represents the imaging range of the imaging section 12104 provided at the rear bumper or the rear door. For example, a bird's-eye view image of the vehicle 12100 as seen from above is obtained by superimposing image data imaged by the imaging sections 12101 to 12104, for example.

[0102] At least one of the imaging sections 12101 to 12104 may have a function for obtaining distance information. For example, at least one of the imaging sections 12101 to 12104 may be a stereo camera composed of a plurality of imaging elements, or may be an imaging element that includes pixels for detecting phase differences.

[0103] For example, the microcomputer 12051 may determine a distance to each three-dimensional object within the imaging areas 12111 to 12114 and a temporal change of the distance (relative speed with respect to the vehicle 12100) on the basis of the distance information obtained from the imaging sections 12101 to 12104, and thereby extract, in particular, as a preceding vehicle, a nearest three-dimensional object that is located on a travel path of the vehicle 12100 and that travels at a predetermined speed (for example, equal to 0 km / h or higher) in substantially the same direction as the vehicle 12100.Furthermore, the microcomputer 12051 can predetermine a following distance to be maintained from a preceding vehicle and perform automatic braking control (including follow-up stop control), automatic acceleration control (including follow-up start control), or the like. Consequently, it is possible to perform cooperative control for automatic driving, which allows the vehicle to drive autonomously without depending on the driver's intervention or the like.

[0104] For example, the microcomputer 12051 can classify three-dimensional object data about three-dimensional objects into three-dimensional object data of a two-wheeled vehicle, a standard-sized vehicle, a large vehicle, a pedestrian, a telephone pole, and other three-dimensional objects based on the distance information obtained from the imaging sections 12101 to 12104, extract the classified three-dimensional object data, and use the extracted three-dimensional objects to automatically avoid an obstacle. For example, the microcomputer 12051 identifies obstacles around the vehicle 12100 as obstacles that the driver of the vehicle 12100 can visually recognize and obstacles that are difficult for the driver of the vehicle 12100 to visually recognize. The microcomputer 12051 then determines a collision risk that indicates a risk of collision with each obstacle.In a situation where the collision risk is equal to or higher than a set value, and thus a possibility of a collision exists, the microcomputer 12051 issues a warning to the driver via the speaker 12061 or the display section 12062 and performs forced deceleration or evasive steering via the drive system control unit 12010. The microcomputer 12051 can thus assist driving to avoid a collision.

[0105] At least one of the imaging sections 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 may detect a pedestrian by determining whether or not there is a pedestrian in captured images from the imaging sections 12101 to 12104. Such detection of a pedestrian is performed, for example, by a procedure for extracting characteristic points in the captured images from the imaging sections 12101 to 12104 as infrared cameras and a procedure for determining whether or not it is the pedestrian by performing pattern matching processing on a series of characteristic points indicating the contour of the object.When the microcomputer 12051 determines that there is a pedestrian in the captured images of the imaging sections 12101 to 12104 and thus detects the pedestrian, the audio / video output section 12052 controls the display section 12062 to display a quadrangular contour line for highlighting, superimposed on the detected pedestrian. The audio / video output section 12052 can also control the display section 12062 to display an icon or the like representing the pedestrian at a desired position.

[0106] The example of the vehicle control system for which the technology according to the present disclosure can be used has been described above. The technology according to the present disclosure can be used among the components described above for the imaging section 12031. Specifically, the Fig. 1 can be used for the imaging device 12031. Applying the technology according to the present disclosure to the imaging section 12031 enables accurate measurement of a distance to, for example, a preceding vehicle, a following vehicle, or another object.

[0107] The above embodiment described the distance measuring device that measures the distance to the distance measuring target; however, this example is not limiting. Alternatively, it may be a time measuring device that irradiates a target with light and measures the time required for the light to return.

[0108] In the above embodiment and modification examples, as shown in Fig. 13 and the like, the first light-receiving section 21A and the second light-receiving section 21B are provided individually; but this example is not limitative. Alternatively, for example, the first light-receiving section 21A and the second light-receiving section 21B may be provided as shown in Fig. 24 may be designed as a single piece. Specifically, for example, a pixel array may be divided into two regions; one may be the first light-receiving section 21A, 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.

[0109] It is particularly noteworthy that the present technology can have the following configurations. According to the present technology with the following configurations, it is possible to more easily provide an optical path for calibrating a distance to a distance measurement target. (1) An optical module comprising: a light-emitting section configured to emit light; a light-receiving section including a first light-receiving section and a second light-receiving section; a first cover member provided on a light emission side of the light-emitting section and configured to direct a first light, which is a portion of the light emitted from the light-emitting section, toward a target and to direct a second light, which is another portion of the light emitted from the light-emitting section, in a direction different from the direction of the target; and a second cover member provided on a light incident side of the light receiving section and configured to direct reflected light, which is the first light reflected from the target, toward the first light receiving section and to direct the second light directed by the first cover member toward the second light receiving section. (2) The optical module according to (1), wherein the first cover member has, in a region of the first cover member, a first reflecting surface provided obliquely with respect to a main surface of the first cover member and configured to reflect the second light in the direction different from the direction of the target. (3) The optical module according to (2), wherein the first cover part has a first recess which is provided in the region of the first cover part, and the first reflective surface is an inner wall of the first recess. (4) The optical module according to (2), wherein the first reflecting surface is an end surface of the first cover part. (5) The optical module according to any one of (1) to (4), wherein the second cover member has, in a region of the second cover member, a second reflecting surface provided obliquely with respect to a main surface of the second cover member and configured to reflect the second light toward the second light-receiving section. (6) The optical module according to (5), wherein the second cover part has a second recess which is provided in the region of the second cover part, and the second reflective surface is an inner wall of the second recess. (7) The optical module according to (5), wherein the second reflecting surface is an end face of the second cover member. (8) The optical module according to any one of (1) to (7), wherein the second light-receiving section is provided so that it extends longitudinally in one direction, the first cover part has, in a region of the first cover part, a first reflecting surface which is provided obliquely with respect to a main surface of the first cover part and is configured to reflect the second light in the direction different from the direction of the target to spread the second light in a direction same as the one direction, and the second cover member has, in a region of the second cover member, a second reflective surface provided obliquely with respect to a main surface of the second cover member and configured to reflect the second light reflected by the first reflective surface toward the second light-receiving section. (9) The optical module according to (8), wherein the second light-receiving section is a single pixel having a shape extending elongated in the one direction. (10) The optical module according to (8), wherein the second light-receiving section includes a plurality of pixels arranged elongated in the one direction. (11) The optical module according to any one of (1) to (10), wherein the first cover member and the second cover member are integrally configured. (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. (13) A distance measuring device comprising: a light-emitting section configured to emit light; a light-receiving section including a first light-receiving section and a second light-receiving section; a first cover member provided on a light emission side of the light-emitting section and configured to direct a first light, which is a portion of the light emitted from the light-emitting section, toward a target and to direct a second light, which is another portion of the light emitted from the light-emitting section, in a direction different from the direction of the target; a second cover member provided on a light incident side of the light-receiving section and configured to direct reflected light, which is the first light reflected from the target, toward the first light-receiving section and to direct the second light directed by the first cover member toward the second light-receiving section; and a processor configured to calculate a distance to the target based on a first pixel signal output by the first light-receiving section in response to the reflected light incident on the first light-receiving section, and configured to calibrate the distance based on a second pixel signal output by the second light-receiving section in response to the second light incident on the second light-receiving section. (14) The distance measuring device according to (13), wherein the processor is configured to calculate the distance by a direct method. (15) The distance measuring device according to (13), wherein the processor is configured to calculate the distance by an indirect method. List of reference symbols 1 distance measuring device 2 Distance measurement target 10 light-emitting section 10S substrate of a light-emitting section 11 light-emitting body 20 light-receiving section 20S substrate of a light-receiving section 21A first light-receiving section 21B second light-receiving section 30 first cover part 30P main interface 31, 61 first reflective surface 32, 62 first depression 33, 65 light-scattering film 40 second cover part 40P main interface 41, 63 second reflective surface 42, 64 second recess 43, 66 infrared filters 50 processor 60 common cover part 60P main interface S1 first pixel signal S2 second pixel signal 100 substrate 101 holders 101A Opening of a light-emitting section 101B Opening of a light-receiving section 102 lens holders 103, 104 lens

Claims

[1] Optical module, comprising: a light-emitting section (10) configured to emit light; a light-receiving section (20) including a first light-receiving section (21A) and a second light-receiving section (21B); a first cover member (30) provided on a light emission side of the light-emitting section (10) and configured to direct a first light, which is a portion of the light emitted by the light-emitting section (10), toward a target and to direct a second light, which is another portion of the light emitted by the light-emitting section (10), in a direction different from the direction of the target; and a second cover member (40) provided on a light incident side of the light-receiving section (20) and configured to direct reflected light, which is the first light reflected from the target, toward the first light-receiving section (21A) and to direct the second light directed by the first cover member (30) toward the second light-receiving section (21B), wherein the first cover part (30) has, in a region of the first cover part (30), a first reflecting surface (31) which is provided obliquely with respect to a main surface (30P) of the first cover part (30) and is configured to reflect the second light in the direction different from the direction of the target, wherein the first cover part (30) either has a first recess (32) provided in the region of the first cover part (30), and the first reflective surface (31) is an inner wall of the first recess (32), or the first reflective surface (31) is an end face of the first cover part (30). [2] The optical module according to claim 1, wherein the second cover member (40) has, in a region of the second cover member (40), a second reflecting surface (41) provided obliquely with respect to a main surface (40P) of the second cover member (40) and configured to reflect the second light toward the second light-receiving section (21B). [3] Optical module according to claim 2, wherein the second cover part (40) has a second recess (42) which is provided in the region of the second cover part (40), and the second reflective surface (41) is an inner wall of the second recess (32). [4] The optical module according to claim 2, wherein the second reflective surface (41) is an end face of the second cover member (40). [5] Optical module according to one of the three preceding claims, wherein the second light-receiving section (21B) is provided so as to extend longitudinally in one direction, the first cover part (30) has the first reflective surface (31) in a region of the first cover part (30) to spread the second light in a direction same as the one direction, and the second cover part (40) has, in a region of the second cover part (40), the second reflective surface (41) configured to reflect the second light reflected by the first reflective surface (31) in the direction of the second light-receiving section (21B). [6] The optical module according to claim 5, wherein the second light-receiving section (21B) is a single pixel having a shape extending elongated in the one direction. [7] An optical module according to claim 5, wherein said second light-receiving section (21B) includes a plurality of pixels arranged elongated in said one direction. [8] Optical module according to one of the preceding claims, wherein the first cover part (30) and the second cover part (40) are configured as one piece. [9] An optical module according to any one of the preceding claims, wherein the first light-receiving section (21A) and the second light-receiving section (21B) are configured integrally. [10] Distance measuring device (1), comprising: a light-emitting section (10) configured to emit light; a light-receiving section (20) including a first light-receiving section (21A) and a second light-receiving section (21B); a first cover member (30) provided on a light emission side of the light-emitting section (10) and configured to direct a first light, which is a portion of the light emitted from the light-emitting section (10), toward a target and to direct a second light, which is another portion of the light emitted from the light-emitting section (10), in a direction different from the direction of the target; a second cover member (40) provided on a light incident side of the light-receiving section (20) and configured to direct reflected light, which is the first light reflected from the target, toward the first light-receiving section (21A) and to direct the second light directed by the first cover member (30) toward the second light-receiving section (21B); and a processor (50) configured to calculate a distance to the target based on a first pixel signal (s1) output by the first light-receiving section (21A) in response to the reflected light incident on the first light-receiving section (21A), and configured to calibrate the distance based on a second pixel signal (s2) output by the second light-receiving section (21B) in response to the second light incident on the second light-receiving section (21B), wherein the first cover part (30) has, in a region of the first cover part (30), a first reflecting surface (31) which is provided obliquely with respect to a main surface (30P) of the first cover part (30) and is configured to reflect the second light in the direction different from the direction of the target, wherein the first cover part (30) either has a first recess (32) provided in the region of the first cover part (30), and the first reflective surface (31) is an inner wall of the first recess (32), or the first reflective surface (31) is an end face of the first cover part (30). [11] Distance measuring device (1) according to claim 10, wherein the processor (50) is configured to calculate the distance by means of a direct method. [12] Distance measuring device (1) according to claim 10, wherein the processor (50) is configured to calculate the distance by means of an indirect method.

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