Distance measuring device

Abstract

The present invention provides a distance measuring device. A reflector module (21) has a pair of deflection mirrors (211, 212) that deflect a transmission wave and a reflection wave to a direction corresponding to the rotation angle of a reflection surface, and rotates according to the drive of a motor. A partition plate separates the pair of deflection mirrors into two parts: a transmission deflection unit (20a) and a reception deflection unit (20b), wherein the transmission deflection unit is a part located on the transmission side, and the reception deflection unit is a part located on the reception side. Each of the pair of deflection mirrors has at least one side that is difficult to transmit the transmission wave, including a side that is close to the transmission window when the reflection surface is facing the transmission part, among the side surfaces sandwiched between the rotation axis of the transmission deflection unit, and a side that is far from the transmission window when the reflection surface is facing the reception part.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS: This international application claims priority based on Japanese Patent Application No. 2019-108652 filed with the Japan Patent Office on June 11, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to a distance measuring device including a deflecting mirror. Background Art

[0003] There is a distance measuring device that irradiates a transmission wave and detects a reflected wave of the irradiated transmission wave from an object to detect the distance of the object. The distance measuring device has a housing, and a transmission window that transmits the transmission wave and the reflected wave is provided at a portion of the housing that allows the transmission wave emitted from the inside of the housing to the outside and the reflected wave incident from the outside of the housing to pass through.

[0004] In addition, the distance measuring device uses a rotationally driven deflecting mirror to deflect and scan the transmission wave, and the transmission wave output from the transmission unit is reflected by the deflecting mirror and emitted in a direction corresponding to the rotation angle of the deflecting mirror through the transmission window. The reflected wave of the transmission wave from the object is reflected by the deflecting mirror through the transmission window and detected by the receiving unit.

[0005] Patent Document 1 discloses a technique in which a deflecting mirror is separated into a region on the transmitting unit side and a region on the receiving unit side in an optical radar device that deflects and scans light. In this optical radar device, since the same deflecting mirror is used to deflect the transmitting light beam and the reflected light beam, an optical short circuit between the transmitting unit side and the receiving unit side is suppressed by arranging a separation wall provided on the reflecting surface of the deflecting mirror.

[0006] Patent Document 1: Japanese Patent Application No. 2018-500603

[0007] However, as a result of detailed studies, the inventors found the following problems.

[0008] When the transmission wave reflected by the deflecting mirror passes through the transmission window, a part of the transmission wave is reflected by the transmission window and becomes a return wave, and sometimes returns to the deflecting mirror without being emitted to the outside of the housing.

[0009] As a structure of the deflecting mirror, for example, a member that transmits the transmission wave and the reflection wave is used as a base, a film that reflects the transmission wave and the reflection wave is provided on the reflection surface, but the film is not provided on the side surface. In the case of such a structure, if the return wave is incident on the side surface of the deflecting mirror, the return wave enters the inside of the deflecting mirror from the side surface.

[0010] As in Patent Document 1, when the same deflecting mirror is used to deflect the transmission wave and the reflected wave, there is a case where the return wave that enters the inside from the side of the portion located on the transmission part side of the deflecting mirror is detected by the receiving part. In other words, there is a case where the return wave passes through the inside of the deflecting mirror and comes out from the side of the portion located on the receiving part side, and is detected by the receiving part. In this way, even if the deflecting mirror is separated into the portion located on the transmission part side and the portion located on the receiving part side by a separation wall, there is a case where a phantom is generated due to the return wave incident from the side of the deflecting mirror, and the phantom is an object that is detected even though it does not actually exist. Summary of the invention

[0011] An object of one aspect of the present disclosure is to reduce the generation of phantom images caused by return waves.

[0012] One method disclosed herein is a distance measuring device, comprising a transmitting unit, a receiving unit, a reflector module, a partition plate, a housing, and a transmission window. The transmitting unit is configured to output a transmission wave. The receiving unit is configured to detect a reflected wave from an object irradiated with the transmission wave. The reflector module is configured to have a pair of deflection mirrors and a reflector support body, and rotates according to the drive of a motor, wherein the pair of deflection mirrors deflect the transmission wave and the reflected wave to a direction corresponding to the rotation angle of the reflection surface, and the reflector support body is sandwiched between the pair of deflection mirrors and supports the pair of deflection mirrors. The partition plate is a plate-shaped component that is configured to separate the pair of deflection mirrors into two parts, a transmission deflection unit and a reception deflection unit, and is configured to rotate integrally with the reflector module, wherein the transmission deflection unit is a part located on the transmitting unit side, and the reception deflection unit is a part located on the receiving unit side. The housing accommodates the transmitting unit, the receiving unit, the reflector module, and the partition plate. The transmission window is provided at the opening of the housing, and can transmit the transmission wave and the reflected wave. Each of a pair of deflection mirrors has a shielding portion on at least one of the side surfaces on both sides of the rotation axis in the transmitting deflection unit, which is close to the transmission window when the reflecting surface is facing the transmitting unit, and the side surfaces on both sides of the rotation axis in the receiving deflection unit, which is far from the transmission window when the reflecting surface is facing the receiving unit, so that the transmitted wave is difficult to pass through the shielding portion.

[0013] According to such a configuration, the occurrence of phantom images due to the return wave can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a three-dimensional diagram showing the appearance of an optical radar device.

[0015] Figure 2 This is an exploded perspective view of an optical radar device.

[0016] Figure 3 This is a three-dimensional diagram showing the structure of a light detection module housed in a housing of an optical radar device.

[0017] Figure 4 This is a diagram of the reflector module viewed from the side.

[0018] Figure 5 This is a diagram of the reflector module viewed from the reflective surface.

[0019] Figure 6 It is a schematic diagram showing the optical path when the return light is incident on the reflection surface of the projection and deflection unit.

[0020] Figure 7 It is a schematic diagram showing the optical path when the return light is incident on the side surface of the projection and deflection unit. DETAILED DESCRIPTION

[0021] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0022] [1.Structure]

[0023] Figure 1 The optical radar device 1 shown is a distance measuring device that measures the distance to an object by emitting light and receiving its reflected light. The optical radar device 1 is mounted on a vehicle for use to detect various objects existing in front of the vehicle. Optical radar is also referred to as LIDAR. LIDAR is the abbreviation of Light Detection and Ranging.

[0024] like Figure 1 As shown, the optical radar device 1 includes a housing 100 and an optical window 200. The housing 100 is a box body made of resin formed into a rectangular parallelepiped with one surface opened.

[0025] Hereinafter, the direction along the long side of the opening of the housing 100 having a substantially rectangular shape is defined as the X-axis direction, the direction along the short side of the opening is defined as the Y-axis direction, and the direction orthogonal to the X-Y plane is defined as the Z-axis direction. In addition, when the optical radar device 1 is installed on the vehicle in such a manner that the X-Z plane becomes horizontal, the left and right in the X-axis direction and the up and down in the Y-axis direction are defined as viewed from the opening side of the housing 100. In addition, the front and back in the Z-axis direction define the opening side of the housing 100 as the front and the depth side as the back.

[0026] like Figure 2 As shown, the light detection module 2 is housed inside the housing 100 . The light detection module 2 includes a light projecting unit 10 , a scanning unit 20 , and a light receiving unit 30 .

[0027] Hereinafter, the structure of the light detection module 2 will be described in detail.

[0028] [2. Scanning unit]

[0029] like Figure 3 As shown in FIG. 1 , the scanning unit 20 includes a reflector module 21, a pair of partition plates 22, 23, and a motor 24. The reflector module 21 is vertically arranged on the motor 24. The reflector module 21 and the pair of partition plates 22, 23 fixed to the reflector module 21 are arranged in a Figure 4 and Figure 5 The rotating shaft indicated by the dot-dash line in the figure is the center and the rotating shaft is driven by the motor 24 to perform a rotation motion.

[0030] The mirror module 21 includes a pair of deflecting mirrors 211 and 212 and a mirror support body 213 .

[0031] Each of the pair of deflecting mirrors 211 and 212 is a flat plate-shaped member having a reflecting surface for reflecting light.

[0032] The reflector support body 213 includes a circular plate portion 213a and a mounted portion 213b. The circular plate portion 213a is a circular plate-shaped portion, the center of which is fixed to the rotating shaft of the motor 24. The mounted portion 213b is a plate-shaped portion on both sides of which a pair of deflection mirrors 211 and 212 are mounted, and is vertically mounted on the circular surface of the circular plate portion 213a. The shape of the mounting surface of the pair of deflection mirrors 211 and 212 in the mounted portion 213b corresponds to the shape of the pair of deflection mirrors 211 and 212.

[0033] In addition, the pair of deflecting mirrors 211 and 212 has a shape in which two rectangles with different widths in the long-side direction are integrated. Specifically, the pair of deflecting mirrors 211 and 212 has a shape in which the central axes of the first rectangle and the second rectangle along the short-side direction of the rectangle are aligned and arranged along the central axis and integrated, wherein the width of the second rectangle in the long-side direction is longer than that of the first rectangle. Hereinafter, in the pair of deflecting mirrors 211 and 212, the portion corresponding to the first rectangle is referred to as a narrow width portion, and the portion corresponding to the second rectangle is referred to as a wide width portion.

[0034] The pair of deflection mirrors 211 and 212 integrated via the installation portion 213b are erected on the disk portion 213a with the wide portion facing downward and the central axis position in the integrated state coincident with the center of the circle of the disk portion 213a. Thus, the mirror module 21 performs a rotational motion centered on the rotation axis of the motor 24.

[0035] The pair of partition plates 22 and 23 is a member that divides a circular plate-shaped member into two semicircular portions, wherein the circular plate-shaped member has the same diameter as the width in the long-side direction of the wide width portion of the pair of deflection mirrors 211 and 212. The pair of partition plates 22 and 23 are fixed to the reflector module 21 in a state of sandwiching the narrow width portion of the pair of deflection mirrors 211 and 212 from both sides and in a state of abutting against the stepped portion of the wide width portion and the narrow width portion of the pair of deflection mirrors 211 and 212.

[0036] Hereinafter, the portion of the pair of deflecting mirrors 211, 212 that is above the pair of partition plates 22, 23, i.e., the portion on the narrow width side, is referred to as the light projection deflection portion 20a, and the portion of the pair of partition plates 22, 23 that is below the pair of partition plates 22, 23, i.e., the portion on the wide width side, is referred to as the light receiving deflection portion 20b.

[0037] [3. Deflecting mirror]

[0038] The deflecting mirrors 211 and 212 are components formed with a reflective film formed on the reflective surface by evaporating a light-reflecting substance on a reflective mirror substrate composed of a light-transmitting component. The reflective surface of the deflecting mirrors 211 and 212 reflects light due to the reflective film, but the side surfaces do not have a reflective film, so light passes through.

[0039] [3-1. Shielding part]

[0040] As in Figure 4 As shown by the shaded portion in the figure, shielding portions 214a and 214b, which are portions that are difficult for light to pass through, are formed on part of the side surfaces of the deflecting mirrors 211 and 212. The shielding portions 214a and 214b are formed by, for example, printing black ink on the surface of a reflector substrate.

[0041] use Figure 6 and Figure 7 The positions where the shielding portions 214a and 214b are formed will be described. Figure 6 and Figure 7 Schematic diagram of the space for housing the light detection module 2 in the housing 100 as viewed from the upper side in the Y-axis direction. Figure 6 and Figure 7 In the figure, the light projecting unit 10 and the light projecting deflecting unit 20a located in the upper space in the Y-axis direction are shown, and the light receiving unit 30 and the light receiving deflecting unit 20b located in the lower space are not shown. Figure 6 and Figure 7 In the figure, the reflecting surface of the deflecting mirror 211 is facing the direction where the light projecting unit 10 and the light receiving unit 30 are located.

[0042] In each of the deflection mirrors 211 and 212, the shielding portion 214a is formed on the side surface of the projection deflection unit 20a that is close to the optical window 200 when the reflection surface faces the projection unit 10, among the side surfaces sandwiching the rotation axis. Figure 6 and Figure 7 In FIG. 1 , the shielding portion 214a in each of the deflecting mirrors 211 and 212 is indicated by the oblique line portion in the side surface of the projection deflecting unit 20a.

[0043] In each of the deflection mirrors 211 and 212, the shielding portion 214b is formed on the side surface of the light receiving deflection unit 20b that is away from the optical window 200 when the reflecting surface faces the light receiving unit 30. Figure 6 and Figure 7 Although not shown in the figure, the shielding portion 214b in each of the deflecting mirrors 211 and 212 is located on the side surface of the light receiving deflecting unit 20b opposite to the side surface where the shielding portion 214a is located.

[0044] [3-2. Low reflection part]

[0045] As in Figure 5 As shown by the hatched portion in FIG. 1 , a portion that is difficult to reflect light, namely a low reflection portion 215, is formed on a portion of the reflection surface of the deflecting mirrors 211 and 212. The low reflection portion 215 is formed by printing the same black ink as the shielding portions 214a and 214b on a reflection film, for example.

[0046] use Figure 6 and Figure 7 The position where the low reflection portion 215 is formed is described. In each of the deflection mirrors 211 and 212, the low reflection portion 215 is formed at the end of the reflection surface of the light projection deflection unit 20a that becomes the optical window 200 side when the reflection surface faces the light projection unit 10. Figure 6 and Figure 7 In the figure, the low reflection part 215 in each of the deflection mirrors 211 and 212 is indicated by the oblique line portion in the reflection surface of the projection and deflection unit 20a. That is, the low reflection part 215 is located at the end of the projection and deflection unit 20a on the same side as the side where the shielding part 214a is located. When the shielding parts 214a, 214b and the low reflection part 215 are formed using the same black ink, the shielding part 214a and the low reflection part 215 are formed continuously.

[0047] [4.Light projection part]

[0048] like Figure 3 As shown, the light projecting unit 10 includes a pair of light emitting modules 11 and 12. The light projecting unit 10 may include a light projection reflecting mirror 15.

[0049] The light emitting module 11 includes a light source 111 and a light emitting lens 112, which are arranged opposite to each other. The light source 111 uses a semiconductor laser. The light emitting lens 112 is a lens that converges the beam width of the light emitted from the light source 111. Similarly, the light emitting module 12 includes a light source 121 and a light emitting lens 122. Since the light emitting module 12 is the same as the light emitting module 11, the description thereof is omitted.

[0050] The light projection and reflection mirror 15 is a reflection mirror that changes the traveling direction of light.

[0051] The light emitting module 11 is arranged so that light output from the light emitting module 11 directly enters the light projection and deflection unit 20 a .

[0052] The light emitting module 12 is arranged so that the light outputted from the light emitting module 12 is bent by approximately 90 degrees in the traveling direction by the light projection reflecting mirror 15 and enters the light projection deflection unit 20 a .

[0053] Here, the light emitting module 11 is configured to output light from the left side to the right side in the X-axis direction, and the light emitting module 12 is configured to output light from the rear side to the front side in the Z-axis direction. In addition, the light reflection mirror 15 is configured not to block the path of light from the light emitting module 11 to the light projection deflection unit 20a.

[0054] [5. Light receiving part]

[0055] The light receiving unit 30 includes a light receiving element 31. The light receiving unit 30 may include a light receiving lens 32 and a light receiving reflecting mirror 33.

[0056] The light receiving element 31 has an APD array in which a plurality of APDs are arranged in a row. APD is an avalanche photodiode.

[0057] The light receiving lens 32 is a lens that collects light arriving from the light receiving deflection unit 20 b .

[0058] The light receiving reflection mirror 33 is a reflection mirror arranged on the left side of the light receiving lens 32 in the X-axis direction and changes the traveling direction of light. The light receiving element 31 is arranged below the light receiving reflection mirror 33 .

[0059] The light receiving reflection mirror 33 is disposed to bend the path of light downward by approximately 90 degrees so that light incident from the light receiving deflection unit 20 b via the light receiving lens 32 reaches the light receiving element 31 .

[0060] The light receiving lens 32 is disposed between the light receiving deflection unit 20b and the light receiving folding mirror 33. The light receiving lens 32 focuses the beam diameter of the light beam incident on the light receiving element 31 to about the element width of the APD.

[0061] [6. Operation of the light detection module]

[0062] The transmission light output from the light emitting module 11 is incident on the light projection deflection unit 20a. In addition, the transmission light output from the light emitting module 12 is bent approximately 90 degrees in the direction of travel at the light projection reflector 15 and is incident on the light projection deflection unit 20a. The transmission light incident on the light projection deflection unit 20a is emitted through the optical window 200 in a direction corresponding to the rotation angle of the reflector module 21. The range of the transmission light irradiated by the reflector module 21 is the scanning range. For example, the front along the Z axis can be set to 0 degrees, and the range of ±60° extending along the X axis direction can be set to the scanning range. Figure 6 and Figure 7In FIG. 1 , the optical path B represents the transmitted light emitted into the scanning range.

[0063] The reflected light from the object to be detected in a predetermined direction corresponding to the rotation position of the reflector module 21, i.e., the emission direction of the transmitted light from the light projection deflection unit 20a, passes through the optical window 200 and is reflected by the light receiving deflection unit 20b. Then, the reflected light is received by the light receiving element 31 via the light receiving lens 32 and the light receiving folding mirror 33.

[0064] [7. Positions of the shielding portion and the low-reflection portion relative to the optical path of the return light]

[0065] In a configuration in which the optical radar device 1 of this embodiment is provided with the optical window 200 and the light is scanned using the rotationally driven deflection mirrors 211 and 212, a part of the transmitted light may become the return light RL and return to the projection and deflection unit 20a. Figure 6 and Figure 7 As shown in FIG. 1 , when the transmission light reflected by the projection deflection unit 20a passes through the optical window 200, a part of the transmission light is further reflected by the optical window 200 and becomes the return light RL, which is not emitted outside the housing 100 but returns to the projection deflection unit 20a. In addition, the original optical path B of the transmission light reflected by the projection deflection unit 20a of the deflection mirror 211 is shown by a solid line, and the optical path of the return light RL is shown by a dotted line. Figure 7 In FIG. 1 , only the return light RL incident on the side surface of the optical window 200 side of the projection and deflection unit 20a of the deflection mirror 211 is shown by a dotted line. In addition, the transmission light reflected by the optical window 200 and becoming the return light RL is shown by a double line.

[0066] Figure 6 The figure shows the case where the return light RL is incident on the reflective surface of the projection light deflection unit 20a of the deflection mirror 211. Assuming that the low-reflection unit 215 does not exist, the return light RL is reflected again by the reflective surface of the projection light deflection unit 20a, as shown by the dotted line, and becomes light emitted in a direction different from the direction it should have been emitted, that is, stray light SL. If the stray light SL is reflected by an object, it returns in the opposite direction on the same path as the emission path and is received by the light receiving unit 30. As a result, an object that is detected although it does not actually exist, that is, a phantom, is generated. The transmission light output from the projection unit 10 is reflected near the center of the reflective surface of the projection light deflection unit 20a, but the return light RL is reflected on the side closer to the optical window 200 than the transmission light.

[0067] In this embodiment, since the low-reflection portion 215 is formed in the region of the reflective surface of the projection light deflection unit 20a that reflects the return light RL, the reflection of the return light RL is suppressed and the amount of stray light SL is reduced. In addition, since the low-reflection portion 215 is formed on the optical window 200 side relative to the region that reflects the transmitted light, that is, the central portion of the reflective surface of the projection light deflection unit 20a, the reflection of the transmitted light is less affected.

[0068] In addition, Figure 7 2 shows a case where the return light RL is incident on the side of the optical window 200 side in the light-projecting deflecting unit 20a of the deflecting mirror 211. Assuming that there is no shielding portion 214a, the return light RL enters the inside of the deflecting mirror 211 from the side, and as shown by the dotted line, passes through the inside of the deflecting mirror 211 from the light-projecting deflecting unit 20a to the light-receiving deflecting unit 20b while repeatedly reflecting. Assuming that there is no shielding portion 214b, the return light RL that passes through the inside of the deflecting mirror 211 and reaches the side of the light-receiving unit 30 side in the light-receiving deflecting unit 20b is emitted from the side to the outside of the deflecting mirror 211 and is received by the light-receiving unit 30. As a result, a phantom image is generated.

[0069] In this embodiment, a shielding portion 214a is formed on the side surface of the light-projecting deflecting unit 20a, which is the entrance when the return light RL enters the inside of the deflecting mirrors 211 and 212. In addition, a shielding portion 214b is formed on the side surface of the light-receiving deflecting unit 20b, which is the exit of the return light RL that passes through the inside of the deflecting mirrors 211 and 212. Thus, the amount of the return light RL that passes through the inside of the deflecting mirrors 211 and 212 and is received by the light receiving unit 30 is reduced.

[0070] [8. Effect]

[0071] According to the above-described detailed embodiments, the following effects are obtained.

[0072] (8a) In the optical radar device 1, each of the pair of deflecting mirrors 211 and 212 has a shielding portion 214a, which is a portion that is difficult for light to pass through, on the side surfaces of the light-projecting deflecting unit 20a sandwiching the rotation axis, and on the side surface that is close to the optical window 200 when the reflecting surface faces the light-projecting unit 10. This can prevent the return light RL incident on the side surface from entering the inside of the deflecting mirrors 211 and 212 from the side surface.

[0073] In addition, in the optical radar device 1, each of the pair of deflecting mirrors 211 and 212 has a shielding portion 214b, which is a portion that is difficult for light to pass through, on the side surfaces of the light receiving deflection unit 20b sandwiching the rotation axis, and on the side surface that is away from the optical window 200 when the reflecting surface faces the light receiving unit 30. This can prevent the return light RL that has entered the inside of the deflecting mirrors 211 and 212 from being emitted from the side surface to the outside of the deflecting mirrors 211 and 212 and being received by the light receiving unit 30.

[0074] According to such a configuration, since the amount of the return light RL that passes through the inside of the deflecting mirrors 211 and 212 and is received by the light receiving unit 30 can be reduced, the generation of ghost images caused by the return light RL can be reduced.

[0075] (8b) In the optical radar device 1, each of the pair of deflecting mirrors 211 and 212 has a low-reflection portion 215 at the end of the reflection surface of the light-projecting deflecting unit 20a on the optical window 200 side when the reflection surface faces the light-projecting unit 10. The low-reflection portion 215 is a portion that is difficult to reflect light. According to such a structure, since it is possible to suppress the return light RL from being reflected by the reflection surface of the light-projecting deflecting unit 20a, and reduce the light amount of stray light SL generated by the reflection, it is possible to further reduce the generation of phantoms caused by the return light RL.

[0076] Furthermore, the transmission light output from the light projecting unit 10 is reflected near the center of the reflection surface of the projection light deflecting unit 20a, and the return light RL is reflected on the optical window 200 side relative to the transmission light. The low reflection unit 215 is formed on the optical window 200 side relative to the region reflecting the transmission light, that is, the center of the reflection surface of the projection light deflecting unit 20a, thereby suppressing the reflection of the return light RL and having little influence on the reflection of the transmission light.

[0077] (8c) In the optical radar device 1, the shielding parts 214a, 214b and the low-reflection part 215 are formed by printing the same black ink on the surfaces of the deflecting mirrors 211 and 212, and the shielding parts 214a and the low-reflection parts 215 are formed continuously. According to such a structure, the shielding parts 214a, 214b and the low-reflection part 215 can be manufactured easily and efficiently.

[0078] In addition, in the present embodiment, the transmitted light is equivalent to the transmitted wave, the light projecting unit 10 is equivalent to the transmitting unit, the reflected light is equivalent to the reflected wave, the light receiving unit 30 is equivalent to the receiving unit, the light projecting deflection unit 20a is equivalent to the transmitting deflection unit, the light receiving deflection unit 20b is equivalent to the receiving deflection unit, the optical window 200 is equivalent to the transmission window, and the black ink is equivalent to the black film.

[0079] [9. Other embodiments]

[0080] As mentioned above, although embodiment of this disclosure was described, this disclosure is not limited to the said embodiment, It goes without saying that various forms can be adopted.

[0081] (9a) In the above embodiment, both the shielding portion 214a and the shielding portion 214b are formed in each of the deflection mirrors 211 and 212. However, only one of the shielding portion 214a and the shielding portion 214b may be formed.

[0082] (9b) In the above embodiment, in each of the deflection mirrors 211 and 212, the shielding portion 214a is formed on the side surface of the projection and deflection unit 20a that is close to the optical window 200 when the reflection surface faces the projection unit 10, among the side surfaces on both sides of the rotation axis. However, the formation position of the shielding portion 214a is not limited thereto. For example, the shielding portion 214a may be formed on the side surfaces on both sides of the rotation axis of the projection and deflection unit 20a, or may be formed on all the side surfaces of the projection and deflection unit 20a.

[0083] (9c) In the above embodiment, in each of the deflecting mirrors 211 and 212, the shielding portion 214b is formed on the side surface of the light receiving deflection unit 20b that is away from the optical window 200 when the reflecting surface faces the light receiving unit 30, among the side surfaces on both sides of the rotation axis. However, the formation position of the shielding portion 214b is not limited thereto. For example, the shielding portion 214b may be formed on the side surfaces on both sides of the rotation axis of the light receiving deflection unit 20b, or may be formed on all the side surfaces of the light receiving deflection unit 20b.

[0084] (9d) In the above embodiment, the shielding portions 214a, 214b and the low-reflection portion 215 are formed by printing the same black ink, but the present invention is not limited thereto. As long as the shielding portions 214a, 214b are formed by a material that is difficult for light to pass through, and the low-reflection portion 215 is formed by a material that is difficult for light to reflect, these materials may be different.

[0085] (9e) In the above embodiment, the optical radar device 1 is exemplified as the distance measuring device, but the type of the distance measuring device is not limited to this. For example, the distance measuring device may be a millimeter wave radar device or the like.

[0086] (9f) The function of one component in the above-mentioned embodiment may be dispersed into a plurality of components, or the functions of a plurality of components may be integrated into a single component. In addition, a part of the structure of the above-mentioned embodiment may be omitted. In addition, at least a part of the structure of the above-mentioned embodiment may be added to or replaced with the structure of other above-mentioned embodiments.

Claims

1. A distance measuring device, comprising: A transmitting unit configured to output a transmission wave; a receiving unit configured to detect a reflected wave from an object irradiated with the transmission wave; The reflector module is configured to include a pair of deflection mirrors and a reflector support body, and is rotated by the drive of a motor, wherein: The pair of deflection mirrors deflect the transmission wave and the reflection wave to directions corresponding to the rotation angle of the reflection surface, and the reflection mirror support body is sandwiched between the pair of deflection mirrors and supports the pair of deflection mirrors; The partition plate is a plate-shaped component that is configured to separate the pair of deflection mirrors into two parts, namely, a transmission deflection part and a reception deflection part, and is configured to rotate integrally with the reflector module, wherein the transmission deflection part is a part located on the transmission part side, and the reception deflection part is a part located on the reception part side; a housing for accommodating the transmitting unit, the receiving unit, the reflector module and the partition plate; and A transmission window is provided in the opening of the housing and is capable of transmitting the transmission wave and the reflection wave. Each deflecting mirror in the pair of deflecting mirrors, The side surfaces of the transmission deflection unit sandwiching the rotation axis on the one side close to the transmission window when the reflecting surface is facing the transmission unit are provided with a shielding portion, the shielding portion is difficult to transmit the transmission wave, and the side surfaces of the transmission deflection unit sandwiching the rotation axis on the one side far from the transmission window when the reflecting surface is facing the transmission unit are not provided with the shielding portion, and / or The shielding portion is provided on the side surfaces on both sides of the rotating axis in the receiving deflection unit, which side surfaces are farther from the transmission window when the reflecting surface is facing the receiving unit, and the shielding portion is not provided on the side surfaces on both sides of the rotating axis in the receiving deflection unit, which side surfaces are closer to the transmission window when the reflecting surface is facing the receiving unit.

2. The distance measuring device according to claim 1, wherein: Each of the pair of deflection mirrors further comprises a low-reflection portion at an end of the reflecting surface of the transmitting deflection portion on the transmission window side when the reflecting surface is facing the transmitting portion, and the low-reflection portion is difficult to reflect the transmitting wave, while the end of the reflecting surface of the transmitting deflection portion on the side opposite to the transmission window side when the reflecting surface is facing the transmitting portion does not comprise the low-reflection portion.

3. The distance measuring device according to claim 2, wherein: The shielding portion and the low-reflection portion are black films.

4. A distance measuring device, comprising: A transmitting unit configured to output a transmission wave; a receiving unit configured to detect a reflected wave from an object irradiated with the transmission wave; The reflector module is configured to include a pair of deflection mirrors and a reflector support body, and is rotated by the drive of a motor, wherein: The pair of deflection mirrors deflect the transmission wave and the reflection wave to directions corresponding to the rotation angle of the reflection surface, and the reflection mirror support body is sandwiched between the pair of deflection mirrors and supports the pair of deflection mirrors; The partition plate is a plate-shaped component that is configured to separate the pair of deflection mirrors into two parts, namely, a transmission deflection part and a reception deflection part, and is configured to rotate integrally with the reflector module, wherein the transmission deflection part is a part located on the transmission part side, and the reception deflection part is a part located on the reception part side; a housing for accommodating the transmitting unit, the receiving unit, the reflector module and the partition plate; and A transmission window is provided in the opening of the housing and is capable of transmitting the transmission wave and the reflection wave. The pair of deflection mirrors is a member that transmits the transmission wave and the reflection wave, and a reflection film is formed on the reflection surface, wherein the reflection film reflects the transmission wave and the reflection wave. Each of the pair of deflection mirrors has a shielding portion on at least one of the side surfaces on both sides of the rotation axis in the transmitting deflection unit, which is close to the transmission window when the reflecting surface is facing the transmitting unit, and the side surfaces on both sides of the rotation axis in the receiving deflection unit, which is far from the transmission window when the reflecting surface is facing the receiving unit, and the shielding portion makes it difficult for the transmitting wave to pass through.

Images