Multiple reflection apparatus

Abstract

To provide a multiple reflection apparatus capable of improving the function of detecting the inclination of a member, including an inclination direction and an inclination angle.SOLUTION: The multiple reflection apparatus 7 according to the present disclosure includes: a multi-surface part 72 having a plurality of reflection surfaces 721 each having a different angle, the reflection surfaces 721 reflecting light emitted from a light source 41 toward a detection unit 431; and a fixed part 71 fixed to a detection target object tiltably supported with respect to the light source 41 and the detection unit 431.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a multi-faceted reflector that can be applied to tilt sensing technology. [Background technology]

[0002] Conventionally, there have been proposed techniques relating to scanner devices equipped with a mirror that controls the reflection direction of light. For example, Patent Document 1 discloses a mirror that changes the emission direction of laser light emitted from a laser light source, and a mirror rotation angle detection means that includes a light receiving sensor that receives reflected light reflected by the second reflection surface out of a first reflection surface and a second reflection surface provided on the mirror. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5293686 Summary of the Invention [Problem to be solved by the invention]

[0004] In the scanner device of Patent Document 1, in order to detect the angle of the mirror, light reflected at a reflection angle corresponding to the tilt of the mirror is detected, so the angular range of the reflected light is wide. If the angular range of the reflected light is wide, the detection range of the light receiving sensor that receives the reflected light must also be wide, which may result in a deterioration of the detection function.

[0005] An object of the present disclosure is to provide a multifaceted reflecting device that can improve the function of detecting the tilt (tilt direction, tilt angle) of a member. [Means for solving the problem]

[0006] The multi-faceted reflection device of the present disclosure comprises a multi-faceted portion that reflects light irradiated from a light source toward a detection portion and has multiple reflective surfaces each having a different angle, and a fixed portion that is fixed to a detection object that is supported so as to be tiltable relative to the light source and the detection portion. [Effects of the Invention]

[0007] The multifaceted reflecting device according to the present disclosure can improve the function of detecting the tilt (tilt direction, tilt angle) of a member. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a configuration diagram of a light source device according to an embodiment. [Figure 2] FIG. 2 is a perspective view of a part of the configuration of the scanner device. [Figure 3] FIG. 1 is a perspective view of a configuration including a multifaceted reflector. [Figure 4] FIG. 10 is a bottom view of the configuration of the multifaceted reflector. [Figure 5] FIG. 2 is a side view of the tilt detector, showing the initial tilt state of the deflection member. [Figure 6A] FIG. 1 is an explanatory diagram (1) illustrating an arrangement in which the light receiving points are not arranged in a straight line. [Figure 6B] FIG. 10 is an explanatory diagram (2) illustrating an arrangement in which the light receiving points are not arranged in a straight line. [Figure 7] FIG. 1 is a side view of the tilt detector, showing the tilted state of the deflector (1). [Figure 8] This is a side view of the tilt detector, showing the tilted state (2) of the deflection member. [Figure 9] This is a side view of the tilt detector, showing the tilted state of the deflector (3). [Figure 10] FIG. 10 is a bottom view of the multifaceted reflecting device of the first modified example. [Figure 11] FIG. 10 is a bottom view of a multifaceted reflecting device of Modification 2. [Figure 12] FIG. 11 is a bottom view of a multifaceted reflecting device of Modification 3. [Figure 13] FIG. 10 is a side view of a multifaceted reflecting device of Modification 4. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a configuration diagram of a light source device 1. The light source device 1 has a function of emitting laser light into space. The light source device 1 can be used as a light source for, for example, a laser distance measuring device or a LiDAR (Light Detection and Ranging) sensor. The light source device 1 includes a control unit 11, a distance measuring optical system 12, an optical system driving circuit 13, and a scanner device 2.

[0010] The control unit 11 controls the operations of the optical system driving circuit 13, the scanner device driving circuit 14, the angle sensor circuit 15, etc. The control unit 11 executes functions and / or methods realized by codes or instructions included in a program stored in a storage unit (not shown). Examples of the control unit 11 include a central processing unit (CPU), a microprocessing unit (MPU), a graphics processing unit (GPU), a microcontroller unit (MCU), a processor core, a multiprocessor, an ASIC, and an FPGA. The control unit 11 may implement each process disclosed in each embodiment using a logic circuit or dedicated circuit formed in an integrated circuit or the like. These circuits may be implemented using one or more integrated circuits, and multiple processes described in each embodiment may be implemented using a single integrated circuit.

[0011] The storage unit (not shown) of the light source device 1 has the function of storing various necessary programs and data. The storage unit can also store acquired information such as measured signals. The storage unit can be realized by various storage media such as an HDD, SSD, or flash memory.

[0012] The distance measurement optical system 12 includes a light-emitting element that emits laser light, optical elements including lenses or mirrors that guide the laser light emitted from the laser light-emitting element, and a light-receiving element that detects the laser light. These optical elements may include a diffuser plate, a light tunnel, a microlens array, a condenser lens, a filter, or the like that adjusts the beam width or luminance distribution. The light-receiving element can receive return light emitted by the laser light-emitting element and reflected by an object outside the light source device 1. The distance measurement optical system 12 emits laser light L1, which is distance measurement light, to a deflection member 6 of the scanner device 2.

[0013] The optical system driving circuit 13 controls the light emission of the light emitting element of the distance measurement optical system 12. The optical system driving circuit 13 also detects the light received by the light receiving element of the distance measurement optical system 12, converts it into an electrical signal, and transmits the information to the control unit 11.

[0014] The scanner device 2 reflects the laser light L1 emitted by the distance measurement optical system 12 in a direction and angle selected from a predetermined solid angle range and emits the reflected light as distance measurement light to the outside of the light source device 1. The scanner device 2 can emit the laser light L1 in different directions, such as laser light L11 or laser light L12, by controlling the angle of the deflector 6. The scanner device 2 also guides light incident from outside the light source device 1 to the distance measurement optical system 12. The light incident from outside the light source device 1 is reflected light L3 reflected by an object outside the light source device 1. Depending on the configuration of the light source device 1, the light source device 1 may guide the laser light L1 to be emitted to the outside via another optical system within the light source device 1.

[0015] The scanner device 2 includes a deflection control device 3 and an inclination detection device 4. The deflection control device 3 of this embodiment includes a yoke member 5, a deflection member 6, and a scanner device drive circuit 14. The inclination detection device 4 of this embodiment includes a light source 41 that emits laser light L2, a first lens 42, a detection circuit board 43, a beam splitter 44, a second lens 46, and an angle sensor circuit 15. The inclination detection device 4 uses the laser light L2 as detection light for detecting the inclination of the deflection member 6. The deflection member 6 also functions as a part of the inclination detection device 4.

[0016] 2 is a perspective view of a portion of the configuration of the deflection control device 3 and the tilt detection device 4 of the scanner device 2. In the description of the scanner device 2, the deflection member 6 side is the upper side of the scanner device 2, and the base member 55 side is the lower side.

[0017] The yoke member 5 includes a first yoke 51 and a second yoke 52 that is different from the first yoke 51 and is arranged in a rotationally symmetrical position about the axis P of the scanner device 2. The first yoke 51 includes a pair of first arm members 53, 53 having first end portions 532 a, 532 a, respectively, and a base member 55 connected to portions of the first arm members 53, 53 opposite the first end portions 532 a, 532 a. The second yoke 52 includes a pair of second arm members 54, 54 having second end portions 542 a, 542 a, respectively, and a base member 55 connected to portions of the second arm members 54, 54 opposite the second end portions 542 a, 542 a.

[0018] First yoke 51 and second yoke 52 have magnetic properties. First arm member 53 and second arm member 54 have body portions 531, 541 that are substantially quadrangular prisms with rectangular cross sections, and protrusions 532, 542 that extend and bend in a substantially L-shape on one side of body portions 531, 541. Protrusions 532, 542 have planar first end portion 532a and second end portion 542a, respectively, at their tips.

[0019] The trunk 531 of the first arm member 53 has a yoke coil 533 wound around its outer periphery (see FIG. 1). The yoke coils 533 of the pair of first arm members 53 are connected to each other in series. Furthermore, the trunk 541 of the second arm member 54 has a yoke coil 543 wound around its outer periphery (FIG. 1 shows only one second arm member 54 and its yoke coil 543). The yoke coils 543 of the pair of second arm members 54 are also connected to each other in series. Therefore, the yoke member 5 and the yoke coils 533, 543 form an electromagnet. The scanner device drive circuit 14 controls the angle of the deflection member 6 by driving the electromagnet in response to instructions from the control unit 11.

[0020] The base member 55 is a member having magnetic properties. The base member 55 includes a disk-shaped first base member 55-1 and a disk-shaped second base member 55-2, each having cutouts 551 on two pairs of opposing side edges 55a. The outer diameter of the first base member 55-1 and the outer diameter of the second base member 55-2 are substantially the same (see FIG. 2). The first base member 55-1 has the cutouts 551 that are substantially rectangular in plan view (details not shown), and a circular opening 553 that penetrates the first base member 55-1 in the thickness direction. As shown in the assembled yoke member 5 in FIG. 2, the opening 553 is located on an axis P that passes through a gap G (magnetic gap) provided between the pair of first end portions 532a and the pair of second end portions 542a.

[0021] The second base member 55-2 has approximately the same thickness as the first base member 55-1. The second base member 55-2 has a circular opening 554 penetrating in the thickness direction (see FIG. 1). As shown in the assembled yoke member 5 in FIG. 2, the opening 554 is disposed on the axis P passing through the gap G. Therefore, the opening 554 is disposed coaxially with the opening 553. The inner diameter of the opening 554 is approximately the same as the inner diameter of the opening 553.

[0022] The first arm member 53 and the second arm member 54 are each housed in a cutout 551 and connected to the first base member 55-1. The first arm member 53 is housed in the cutout 551 with its face abutting against the inner surface 551a of the first base member 55-1 toward the center and its end 531a substantially abutting against the upper surface of the second base member 55-2. Similarly, the second arm member 54 is housed in the cutout 551 with its face abutting against the inner surface 551a of the first base member 55-1 toward the center and its end 541a substantially abutting against the upper surface of the second base member 55-2 (see also FIG. 4). Therefore, the second base member 55-2 is disposed overlapping the first base member 55-1 so as to cover the ends 531a, 541a of the first arm member 53 and the second arm member 54 housed in the cutout 551.

[0023] 2, the first end portions 532a, 532a of the pair of first yokes 51 are arranged to face each other. The second end portions 542a, 542a of the pair of second yokes 52 face each other in a direction (second direction D2) perpendicular to the facing direction (first direction D1) of the first end portions 532a, 532a in a plan view.

[0024] 3 is a perspective view showing the deflection member 6. The deflection member 6 is an optical member that is disposed between the pair of first end portions 532a and between the pair of second end portions 542a in a plan view of the scanner device 2 (see FIGS. 1 and 2). The deflection member 6 includes a reflector 61, a permanent magnet 62, and a multifaceted reflecting device 7. The reflector 61 has a circular, flat plate shape and includes a reflecting portion 611 that is a functional surface that reflects the laser light L1 (see FIG. 2). The reflecting portion 611 includes a metal reflective film that is provided by a method such as vapor deposition.

[0025] The permanent magnet 62 is fixed to the reflector 61. The control unit 11 applies an external force to the deflection member 6 via the yoke member 5 and the permanent magnet 62 by passing a current through the yoke coils 533 and 543, thereby controlling the tilt direction and tilt angle of the deflection member 6.

[0026] The multifaceted reflecting device 7 includes a fixed portion 71 and a multifaceted portion 72. The fixed portion 71 includes a base portion 711, a foundation portion 712, and a main portion 713. The base portion 711 is fixed to the permanent magnet 62. The base portion 711 has a substantially rectangular plate shape. The base portion 711 has recessed portions 711a at opposing positions and a recessed portion 711b near one corner. The recessed portion 711a has a substantially semicircular shape that curves from the side wall of the base portion 711 toward the center. The recessed portion 711b serves as a mark for identifying the orientation when fixing the multifaceted reflecting device 7 to the permanent magnet 62. The recessed portion 711a functions as a positioning recess. The deflection member 6 has, for example, a pair of cylindrical holding posts (not shown) on the back surface of the permanent magnet 62 or the reflector 61, and the holding posts are arranged in contact with the recesses 711a, thereby enabling the circumferential position of the polygonal reflecting device 7 to be determined. The polygonal reflecting device 7 may also be positioned by rotating it in the circumferential direction using the pair of holding posts, thereby adjusting the angle of the polygonal portion 72 relative to the deflection member 6.

[0027] A base portion 712 having a truncated cone shape is fixed to the surface of the base portion 711 opposite to the surface fixed to the permanent magnet 62. The base portion 712 is connected to a main portion 713 at an end portion opposite to one end portion in the axial direction connected to the base portion 711. The main portion 713 has a short cylindrical shape, and the end portion opposite to the one end portion in the axial direction connected to the base portion 712 is a tip surface 713a. The polyhedral portion 72 is formed on the tip surface 713a.

[0028] FIG. 4 is a bottom view of the multifaceted reflecting device 7. The multifaceted portion 72 has a plurality of reflecting surfaces 721. The reflecting surfaces 721 have a generally hexagonal shape with smooth surfaces. The reflecting surfaces 721 are arranged at different angles to one another, forming a convex spherical crown shape as a whole (see FIG. 3). The multifaceted portion 72 has the reflecting surfaces 721 arranged in a honeycomb pattern with no gaps. As shown in FIG. 4, the reflecting surfaces 721 are arranged in a straight line with equal angles. The reflecting surfaces 721 arranged in a straight line with equal angles are arranged adjacent to each other in multiple rows. In this embodiment, the multifaceted portion 72 having a generally spherical crown shape has seven rows of the reflecting surfaces 721 arranged in a straight line in a 60-degree direction. Furthermore, as shown in FIG. 4, the reflecting surfaces 721 are arranged in a generally spherical band shape (approximately concentric circles) around the reflecting surface 721 through which the axis P passes. In this embodiment, six reflecting surfaces 721 are arranged around the reflecting surface 721 through which the axis P passes, and twelve reflecting surfaces 721 are arranged around them in a substantially spherical zone shape (substantially concentric circles). The tip surface 713a of the polyhedral portion 72 is formed by cutting.

[0029] In addition to being formed by cutting, the plurality of reflecting surfaces 721 may also be formed by, for example, resin molding. When forming reflecting surface 721 by resin molding, reflecting surface 721 may be formed by mirror-finishing the surface of a flat reflecting member and fixing the back surface of reflecting surface 721 formed on the reflecting member to tip surface 713a by adhesive or the like.

[0030] 5 is a side view schematically showing the tilt detection device 4. The light source 41 is a laser light emitting element that emits laser light L2 as detection light. The first lens 42 is a condensing lens that condenses the laser light L2 emitted from the light source 41. The laser light L2 condensed by the first lens 42 passes through an aperture plate 45 and is irradiated onto a beam splitter 44. The aperture plate 45 has an opening (aperture) and has the function of determining the transmission path of the laser light L2 and changing the irradiation range (light width) of the laser light L2.

[0031] The beam splitter 44 is a half mirror. The beam splitter 44 transmits a portion of the laser light L2 emitted from the first lens 42 along the axis P to the polyhedral portion 72 of the polyhedral reflecting device 7. The beam splitter 44 also reflects a portion of the laser light L2 reflected by the polyhedral portion 72 and guides the reflected portion to the detecting unit 431. A second lens 46 is disposed between the beam splitter 44 and the detecting unit 431. The second lens 46 is a focusing lens that focuses a portion of the laser light L2 reflected by the beam splitter 44.

[0032] 5, the permanent magnet 62 has a generally circular disk shape that is rotationally symmetric about the axis P along which the deflection member 6 is not tilted. The permanent magnet 62 has one of an S pole and an N pole at one end in the thickness direction (direction of the axis P), and the other of the S pole and N pole at the other end.

[0033] The deflection member 6 has a rotation center Q, which is an imaginary point. The deflection member 6 has a polygonal portion 72 of the polygonal reflecting device 7 on the opposite side to the reflecting portion 611 and at a position away from the rotation center Q. The multiple reflecting surfaces 721 of the polygonal portion 72 are arranged at equal distances from the rotation center Q.

[0034] As shown in the enlarged view of FIG. 5, when the deflector 6 is not tilted (initial state), the laser light L2 irradiated onto the multifaceted portion 72 is incident on the multiple reflecting surfaces 721a, 721b, and 721c and is reflected by each of the reflecting surfaces 721a-c. In the enlarged view of FIG. 5, the optical axis of the reflected light (light component) reflected by each reflecting surface 721 is shown. Each reflecting surface 721 reflects light at the same reflection angle as the angle of incidence of the incident light. For example, the reflected light (light component) L2b reflected by the reflecting surface 721b has an optical axis that is emitted perpendicular to the reflecting surface 721b because the incident angle of the laser light L2 is 0 degrees (normal incidence). On the other hand, when the incident angle of the laser light L2 is greater than 0 degrees, the reflected light (light components) L2a and L2c reflected by the reflecting surfaces 721a and 721c are reflected at the same reflection angle as the angle of incidence. The irradiation range of the laser light L2 is a range that does not irradiate the base portion 712 of the multifaceted reflecting device 7 when the deflecting member 6 is tilted at a preset maximum tilt angle.

[0035] The deflection member 6 is supported by a support unit (not shown) so as to be rotatable about two axes. The scanner device drive circuit 14 controls the rotation of the deflection member 6 about a rotation center point Q. For example, the deflection member 6 can rotate about a first direction D1 or a second direction D2 relative to the rotation center point Q. The deflection member 6 may be supported by a support unit that is rotatable about three or more axes so as to be rotatable about the rotation center point Q. In addition, in an unloaded state where no magnetic field from the electromagnet is applied, the deflection member 6 is biased by a resilient force or the like toward a reference position (the state of the deflection member 6 in FIG. 1) where the axis P of the yoke member 5 and the reflecting portion 611 are approximately perpendicular to each other.

[0036] The scanner device drive circuit 14 shown in FIG. 1 includes yoke coils 533 and 543 as load circuits and a driver circuit (or switching circuit), not shown. The control unit 11 controls the scanner device drive circuit 14 to supply excitation current to the yoke coils 533 and 543. This generates magnetic fields in the first magnetic path C1 of the first yoke 51 and the second magnetic path C2 of the second yoke 52, generating a magnetic field in a first direction D1 between the first end 532a of the first yoke 51 and a magnetic field in a second direction D2 between the second end 542a of the second yoke 52 with intensities specified by the control unit 11. The permanent magnet 62 is subjected to attractive or repulsive forces by the magnetic fields generated in the first direction D1 and the second direction D2. Depending on the intensities of these magnetic fields, the tilt direction and tilt angle of the deflection member 6 are controlled around the rotation center point Q so as to achieve a predetermined tilt direction and tilt angle.

[0037] The detection circuit board 43 has a detection unit 431 which is a light receiving element. The detection unit 431 is arranged on the opposite side of the deflection member 6 from the reflection unit 611, i.e., on the side of the multifaceted reflecting device 7 (see FIG. 5, etc.). The detection unit 431 detects the laser light L2 reflected by the multifaceted unit 72.

[0038] 5 and 7 to 9 are side views of the tilt detection device, and also show schematic plan views of the light receiving unit 432 provided in the detection unit 431. The detection unit 431 is a two-dimensional sensor, and for example, a profile sensor which is a collection of pixels is used. The light receiving unit 432 has pixels arranged in a lattice pattern, and detects pixel information (received light intensity) for each column in two orthogonal directions (X-axis direction Dx and Y-axis direction Dy). The control unit 11 detects the position (e.g., center of gravity) of the laser light L2 detected based on the pixel information as coordinate data. Note that a CCD or CMOS sensor may be used as the detection unit 431.

[0039] The reference point O of the light receiving unit 432 is arranged so that the light receiving point of the laser light L2 received when the deflection member 6 is not tilted (initial state) is located approximately in the center of the light receiving unit 432. The size of the irradiation area (light receiving point) of the laser light L2 received by the light receiving unit 432 is determined by the size of the reflecting surface 721 where the laser light L2 is reflected and the focal length of the second lens 46.

[0040] Here, the laser beam L2 may be received at two or more light receiving points by the light receiving unit 432. When a profile sensor is used, if two or more light receiving points (or light receiving areas, the same applies hereinafter) are detected arranged in a straight line in the X-axis direction Dx (and / or Y-axis direction Dy), the outputs in the X-axis direction Dx (and / or Y-axis direction Dy) on the light receiving unit 432 may be superimposed, which may deteriorate the detection accuracy of pixel information (for example, it may become difficult to separate the laser beam L2 at two points and identify accurate position coordinates).

[0041] In this embodiment, when the recessed portion 711a of the fixed portion 71 of the multifaceted reflecting device 7 is arranged in the first direction D1 and the recessed portion 711b is arranged in the lower left of FIG. 4, the linearly arranged multiple reflecting surfaces 721 are arranged in the first direction D1. The multiple reflecting surfaces 721 arranged in the first direction D1 are defined as a reference line S, and the linearly arranged multiple reflecting surfaces 721 are arranged horizontally around the axis P at intervals of 60 degrees from the reference line S. The beam splitter 44 is arranged with its surface that guides light to the detection unit 431 facing between the first direction D1 and the second direction D2 (rear right of FIG. 5), with the light-guiding surface tilted upward. The detection unit 431 is arranged between the first direction D1 and the second direction D2 (rear right of FIG. 5) at a position where the beam splitter 44 receives the light guided by it. The two orthogonal directions of the light-receiving unit 432 in FIG. 5 are the X-axis direction Dx, which is the horizontal direction, and the Y-axis direction Dy, which is the vertical direction.

[0042] In this case, there are three ways to arrange the light receiving points so that they are not aligned in a straight line in the X-axis direction Dx (and / or Y-axis direction Dy). The first method is to rotate the deflector 6 (or the multifaceted reflector 7) in the circumferential direction around the axis P (horizontal direction in FIG. 5) (for example, 15 degrees, 45 degrees, or 75 degrees from the reference line S). The second method is to rotate two orthogonal directions of the light receiving unit 432 around the normal line (such as the central axis) of the light receiving unit 432 (for example, 15 degrees, 45 degrees, or 75 degrees). The third method will be described with reference to FIGS. 6A and 6B.

[0043] FIG. 6A is a simplified plan view of the polyhedral portion 72, the incident surface PL of the beam splitter 44, and the light receiving portion 432. FIG. 6B is a front view of FIG. 6A. The enlarged view of FIG. 6B is a view taken along the arrow A-A' (the beam splitter 44 itself is not shown). The polyhedral portion 72 has a plurality of reflecting surfaces 721 (referred to as "linear reflecting surfaces" in the explanation of the enlarged views of FIGS. 6A and 6B) arranged in a line at intervals of R degrees in the horizontal direction around the axis P from the reference line S. In this embodiment, R=60 degrees. In this case, as shown in the enlarged views of FIGS. 6A and 6B, the incident surface PL is tilted counterclockwise by an angle θ1 from the linear reflecting surface that overlaps with the reference line S. Because the linear reflecting surfaces are arranged at intervals of R degrees, the angle of the incident surface PL relative to each linear reflecting surface is R×m (m is an integer)+θ1 (60·m+θ1 in this embodiment). The angle at which the light receiving unit 432 is tilted in the vertical direction is the angle θ2 formed between the incident surface PL and the Y-axis direction Dy of the light receiving unit 432. In this case, the light receiving unit 432 is tilted clockwise from the incident surface PL by the angle θ2. Here, the arrangement in which the light receiving points are aligned in a straight line in the Y-axis direction Dy (and / or the X-axis direction Dx) of the light receiving unit 432 occurs when the light receiving points are aligned in two orthogonal directions (the X-axis direction Dx and the Y-axis direction Dy), i.e., the light receiving points are spaced at 90-degree intervals, and the arrangement is 90×n (n is an integer). Therefore, to arrange the light receiving points so that they are not aligned in a straight line in the Y-axis direction Dy (and / or the X-axis direction Dx), the positions and / or orientations (postures) of the deflector 6 (or the multifaceted reflecting device 7), the beam splitter 44, and the light receiving unit 432 may be set so that θ1 + R·m + θ2 ≠ 90n (n and m are integers). 5 and 7 to 9, θ1 = 0 and θ2 = 0. When a CCD or CMOS sensor is used as the detection unit 431, accurate position coordinates can be identified even if the light-receiving points are arranged in a straight line in the X-axis direction Dx (and / or Y-axis direction Dy).

[0044] The control unit 11 can calculate and determine the position of the reflecting surface 721 from tilt information about the deflecting member 6 and a signal corresponding to the position of the optical axis (light-receiving point) of the laser light L2 or the distribution position of the laser light L2 detected by the detection unit 431 (hereinafter, both positions are also referred to as "optical axis position signal"). This allows the control unit 11 to detect the tilt (tilt direction and tilt angle) of the deflecting member 6. Specifically, the control unit 11 has a function of separately providing an angle sensor that detects the tilt state of the deflecting member 6, determining from which reflecting surface 721 light is guided to the light-receiving unit 432 based on tilt information obtained from the angle sensor, which indicates an approximate tilt angle, and detecting the tilt of the deflecting member 6 based on the determined information about the reflecting surface 721 and the coordinate data of the laser light L2 detected by the light-receiving unit 432. Note that the approximate tilt state of the deflecting member 6 may be determined from the input voltage (drive voltage) or input current (drive current) to the yoke coils 533 and 543, in addition to being obtained by the angle sensor.

[0045] For example, FIGS. 5 and 7 to 9 show the optical axis and light-receiving point of the laser beam irradiated onto the detection unit 431 when the tilt (tilt direction and tilt angle) of the deflector 6 is changed. The tilt of the deflector 6 is greater according to FIGS. 5 and 7 to 9. As shown in FIG. 5, when the optical axis L of the laser beam L2 coincides with the axis P and the deflector 6 is not tilted with respect to the optical axis L, the irradiation range of the laser beam L2 is irradiated onto the reflecting surfaces 721a, 721b, and 721c. In this case, a portion of the light (L2b) reflected by the reflecting surface 721b is irradiated onto the detection unit 431. Meanwhile, the laser beam L2 irradiated onto the reflecting surfaces 721a and 721c is emitted as reflected light L2a and L2c, but is not irradiated onto the beam splitter 44 or does not reach the light-receiving unit 432 of the detection unit 431, and is therefore not detected by the light-receiving unit 432. The detection unit 431 sets the reference point O to a point that substantially coincides with the optical axis B from the reflecting surface 721b in this case.

[0046] 7, when the deflection member 6 is tilted to the right in FIG. 7 in the first direction D1, the reflecting surface 721b moves to the left with respect to the axis P. From the enlarged view of FIG. 7, the irradiation range of the laser beam L2 is irradiated onto the reflecting surfaces 721a, 721b, and 721c. Of the reflecting surfaces 721 irradiated with the laser beam L2, the reflecting surface 721b emits the laser beam L2 as light (L2b) having an optical axis B that is shifted to the upper left in FIG. 7 with respect to the optical axis L at the time of incidence. Because the optical axis B is tilted to the right with respect to the optical axis L, the laser beam L2 is irradiated to the detection unit 431 shown in FIG. 7 as reflected light L2b whose optical axis B is located to the upper left of the reference point O. Note that the laser beam L2 incident on the reflecting surfaces 721a and 721c is emitted as reflected light L2a and L2c, but is not irradiated onto the beam splitter 44 and is therefore not detected by the detection unit 431.

[0047] 8, when the deflector 6 is tilted more to the right in FIG. 8 in the first direction D1, the reflecting surface 721b moves leftward with respect to the axis P. As can be seen from the enlarged view of FIG. 8, the irradiation range of the laser beam L2 is such that the reflecting surfaces 721a, 721b, 721c, and 721d are irradiated with the laser beam L2. Of the reflecting surfaces 721 irradiated with the laser beam L2, the reflecting surfaces 721b and 721c emit the laser beam L2 as light (L2b, L2c) having optical axes B and C that are shifted to the upper left in FIG. 8 with respect to the optical axis L at the time of incidence. Because the optical axis B is tilted to the right with respect to the optical axis L, the reflected light L2b with the optical axis B positioned to the upper left of the reference point O is irradiated to the detecting unit 431 shown in FIG. 8 is irradiated as reflected light L2c where optical axis C is located on the lower right side of reference point O. Laser light L2 incident on reflecting surfaces 721a and 721d is emitted as reflected light L2a and L2d, but is not irradiated to beam splitter 44 and is therefore not detected by detection unit 431.

[0048] 9, when the deflection member 6 is significantly tilted to the right in FIG. 9 in the first direction D1, the reflecting surface 721b moves to the left with respect to the axis P. From the enlarged view of FIG. 9, the irradiation range of the laser beam L2 is irradiated onto the reflecting surfaces 721b, 721c, and 721d. Of the reflecting surfaces 721 irradiated with the laser beam L2, the reflecting surface 721c emits the laser beam L2 as light (L2c) having an optical axis C that substantially coincides with the optical axis L at the time of incidence. Because the optical axis C substantially coincides with the optical axis L, the laser beam L2 is irradiated as reflected light L2c onto the detecting unit 431 shown in FIG. 9 at a position where the optical axis C substantially coincides with the reference point O. Note that the laser beam L2 incident on the reflecting surfaces 721b and 721d is emitted as reflected light L2b and L2d, but is not irradiated onto the beam splitter 44 and is therefore not detected by the detecting unit 431.

[0049] In this way, the reflecting surface 721 has different surfaces that reflect the laser light L2 depending on the inclination of the deflecting member 6, as shown in Figures 5 and 7 to 9, and has the function of displacing the position of the optical axis irradiated onto the detection unit 431 depending on the angle of each reflecting surface 721.

[0050] The control unit 11 determines the inclination (tilt direction and tilt angle) of the deflection member 6 based on the light receiving position of the laser light L2 received by the light receiving unit 432 and the reflecting surface 721 that reflects the laser light L2. The control unit 11 calculates the position of the optical axis of the laser light L2 irradiated to the light receiving unit 432 with respect to a reference point O, and can thereby determine the inclination of the deflection member 6. At this time, since tilt information of the deflection member 6 is separately acquired by an angle sensor, this tilt information is also included in the calculation. The control unit 11 may determine the correspondence relationship between the position of the optical axis with respect to the reference point O and the inclination of the deflection member 6 by calculation, or may determine it in advance by referring to a correspondence table.

[0051] Figures 5 and 7 to 9 show the laser light L2 reflected by the reflecting surface 721 moving in the first direction D1, but the detection unit 431 can also output an optical axis position signal to the control unit 11 to cause the control unit 11 to detect the inclination of the deflection member 6 with respect to the second direction D2 (or a direction including the first direction D1 and the second direction D2) when the laser light L2 moves in the second direction D2 (or a direction including the first direction D1 and the second direction D2).

[0052] In the multifaceted reflecting device 7 of the present embodiment, the reflecting surface 721 that reflects the laser light L2 varies depending on the inclination of the deflecting member 6, and therefore, by identifying the reflecting surface 721 that reflected the laser light L2, it becomes possible to detect the inclination of the deflecting member 6 over a wide range. In addition, since it is sufficient that the detecting unit 431 is irradiated with the reflected light from the reflecting surface 721, there is no need to widen the detection range of the detecting unit 431.

[0053] (Variation 1) Next, a first modification of the first embodiment will be described. Fig. 10 is a bottom view of the polygonal portion 72A of the polygonal reflecting device 7 of the first modification. In the description of the polygonal reflecting device 7 of the first modification, the same components as those in Fig. 3 will be denoted by the same reference numerals, and the description thereof will be omitted or simplified.

[0054] The polygonal reflecting device 7 of the first modification has a polygonal portion 72A instead of the polygonal portion 72. The polygonal portion 72A has a plurality of reflecting surfaces 721A. The reflecting surfaces 721A have a generally triangular shape with a smooth surface. Since the reflecting surfaces 721A are arranged along the spherical crown-shaped tip surface 713a, each of the plurality of reflecting surfaces 721A has a different angle.

[0055] In the multifaceted reflecting device 7 of the first modification, the reflecting surface 721A has more reflecting surfaces than the reflecting surface 721 of the first embodiment, and therefore the inclination of the deflecting member 6 can be detected more accurately even if the area of ​​the light receiving section 432 is the same.

[0056] (Variation 2) Next, a second modification of the first embodiment will be described. Fig. 11 is a bottom view of the polygonal portion 72B of the polygonal reflecting device 7 of the second modification. In the description of the polygonal reflecting device 7 of the second modification, the same components as those in Fig. 3 will be denoted by the same reference numerals, and the description thereof will be omitted or simplified.

[0057] The multifaceted reflecting device 7 of the second modification includes a multifaceted portion 72B instead of the multifaceted portion 72. The multifaceted portion 72B has a plurality of reflecting surfaces 721B. The reflecting surfaces 721B have a generally circular shape with a smooth surface. Since the reflecting surfaces 721B are arranged along the spherical crown-shaped tip surface 713a, each of the plurality of reflecting surfaces 721B has a different angle.

[0058] Although the multifaceted reflecting device 7 of the second modification has a small gap between the reflecting surfaces 721B, it can detect the tilt of the deflecting member 6 with the same accuracy as the reflecting surface 721 of the first embodiment.

[0059] (Variation 3) Next, a third modification of the first embodiment will be described. Fig. 12 is a bottom view of the polygonal portion 72C of the polygonal reflecting device 7 of the third modification. In the description of the polygonal reflecting device 7 of the third modification, the same components as those in Fig. 3 will be denoted by the same reference numerals, and the description thereof will be omitted or simplified.

[0060] The polygonal reflecting device 7 of Modification 3 has a polygonal portion 72C instead of the polygonal portion 72. The polygonal portion 72C has a plurality of reflecting surfaces 721C. The reflecting surfaces 721C have a generally hexagonal shape with smooth surfaces. The reflecting surfaces 721C are spaced apart at regular intervals and arranged along the spherical crown-shaped tip surface 713a. Each of the reflecting surfaces 721C has a different angle.

[0061] In the polygonal reflecting device 7 of the modified example 3, the reflecting surfaces 721C are arranged at intervals, which makes it easy to form the polygonal portion 72C. The polygonal reflecting device 7 of the modified example 3 is used in a situation where the precision of the tilt of the deflecting member 6 is not high.

[0062] (Variation 4) Next, a fourth modification of the first embodiment will be described. Fig. 13 is an enlarged side view of the polygonal portion 72D of the polygonal reflecting device 7 of the fourth modification. In the description of the polygonal reflecting device 7 of the fourth modification, the same components as those in Fig. 3 will be denoted by the same reference numerals, and the description thereof will be omitted or simplified.

[0063] The main part 713D of the multifaceted reflecting device 7 is fixed to the surface of the base part 712 opposite to the surface fixed to the base part 711. The main part 713D has a cylindrical shape and has a recessed surface 713b recessed into the inside of the main part 713D on the surface opposite to the surface fixed to the base part 712. The multifaceted part 72D is formed along the recessed surface 713b. A plurality of reflective surfaces 721D are arranged and fixed by adhesive or the like. The multifaceted part 72D has a plurality of reflective surfaces 721D. The plurality of reflective surfaces 721D are adjacent to each other, arranged without gaps, and fixed by adhesive or the like so as to cover the recessed surface 713b. The reflective surface 721D has a substantially hexagonal shape with a smooth surface. The plurality of reflective surfaces 721D arranged along the recessed surface 713b each have a different angle. Note that, as in this embodiment, the plurality of reflective surfaces 721D may be formed by cutting.

[0064] In the polygonal reflecting device 7 of Modification 4, the irradiation range of the laser light L2 is irradiated onto reflecting surfaces 721a, 721b, and 721c. In this case, the reflected light L2a reflected by reflecting surface 721a is light tilted to the left of the optical axis L and therefore exits toward the right in FIG. 13. The reflected light L2b reflected by reflecting surface 721b is parallel to the optical axis L and therefore is reflected in approximately the same direction as the incident light. The reflected light L2c reflected by reflecting surface 721c is light tilted to the right of the optical axis L and therefore exits toward the left in FIG. 13. Therefore, the direction in which the reflected light exits differs depending on whether the surface of the trunk part 713 is a spherical crown-shaped tip surface 713a or an inwardly recessed surface 713b.

[0065] As described above, the present disclosure has described a multi-surface reflecting device 7 that can improve the detection function of the tilt (tilt direction, tilt angle) of a component. The multi-surface reflecting device 7 includes a plurality of reflecting surfaces 721 that reflect light (L2) emitted from a light source 41 toward a detecting unit 431 and each reflecting surface has a different angle, and a fixed portion 71 that is fixed to a detection object that is tiltably supported relative to the light source 41 and the detecting unit 431.

[0066] Since the tilt detection device 4 can detect the tilt of the deflection member 6 without irradiating detection light from the functional surface side of the deflection member 6, the light source 41 and the detection unit 431 can be provided inside the yoke member 5 or outside the yoke member 5 on the side opposite to the deflection member 6. This allows the tilt detection device 4 and devices such as the light source device 1 equipped with the tilt detection device 4 to be miniaturized. For example, by applying the tilt detection device 4 of the present disclosure, a distance measuring device for LiDAR can be configured to be compact while still having a tilt detection function.

[0067] Furthermore, by using the polygonal reflecting device 7, the tilt detecting device 4 can detect the tilt of the deflecting member 6 over a wide range of tilt angles. Furthermore, the tilt detecting method using the tilt detecting device 4 is a method of identifying the reflecting surface 721 that illuminates the detecting section 431 with light irradiated onto the polygonal portion 72 of the polygonal reflecting device 7. Therefore, the tilt of the deflecting member 6 can be detected without widening the detection range, and degradation of the detection function can be suppressed.

[0068] This concludes the description of the embodiment of the present disclosure, but the aspects of the present disclosure are not limited to this embodiment.

[0069] For example, a polarizing beam splitter may be provided as one of the beam splitters instead of the beam splitter. The tilt detection device may also have a quarter-wave plate between the deflector and the beam splitter. In this case, the light source is a laser-emitting diode that emits laser light L2. Therefore, the laser light L2 is linearly polarized light. The polarizing beam splitter has spectral characteristics of reflecting one of S-polarized and P-polarized light and transmitting the other of S-polarized and P-polarized light. The tilt detection device reflects the laser light L2 emitted from the light source toward the quarter-wave plate as linearly polarized first-polarized light. The quarter-wave plate converts the laser light L2, which is the first-polarized light guided by the polarizing beam splitter, from linearly polarized light to circularly polarized light and guides it to the multifaceted portion of the multifaceted reflector of the deflector. The reflecting surface of the polyhedral portion onto which the laser light L2 is incident is tilted in accordance with the tilt of the deflecting member so that the laser light L2 is reflected by the quarter-wave plate at an angle from the optical axis position (optical axis L) of the reflecting surface to the optical axis of the reflecting surface. The quarter-wave plate converts the laser light L2 guided from the reflecting surface from circularly polarized light to linearly polarized light, and outputs it to the polarizing beam splitter as second-polarized light with a polarization direction perpendicular to the first-polarized light. The polarizing beam splitter reflects the laser light L2 guided from the quarter-wave plate and guides it to the detection unit.

[0070] In the present disclosure, the reflective surfaces of the polygonal portion have a substantially hexagonal shape, but are not limited to this shape. For example, they may be rectangular or circular. It is sufficient that the multiple reflective surfaces have the same size.

[0071] In the present disclosure, an example has been described in which the detection unit is a profile sensor, but the detection unit may also be a position sensitive detector (PSD) or a two-dimensional image sensor.

[0072] In addition, the light source and the detector may be interchanged in the configuration of the tilt detection device. When the light source and the detector are interchanged in the tilt detection device, the polarizing beam splitter has the function of reflecting the first polarized light and transmitting the second polarized light having a polarization direction perpendicular to the first polarized light.

[0073] Furthermore, the tilt detection device may have the light source, lens, beam splitter, and detector disposed outside the yoke member. The laser light L2 is guided through the opening provided in the thickness direction of the base member.

[0074] The tilt detection device may also be provided with a separate light leakage absorption device that absorbs light leakage. The light leakage absorption device is a device that absorbs light irradiated from a light source, a beam splitter, a reflecting surface, or external sources onto areas outside the target irradiation area. This can prevent degradation of detection accuracy and malfunction of each device due to light leakage.

[0075] The distance measurement optical system of the present disclosure may also be used to guide light for purposes other than distance measurement. The tilt detection device may also be applied to detecting the tilt of other optical components that have the function of rotating around a rotation center point Q, not limited to deflecting components. The optical component whose tilt is detected by the tilt detection device may have other functional surfaces, such as light reflection or transmission. Furthermore, the tilt detection device may be used as a device for detecting the tilt of components other than optical components, instead of deflecting components.

[0076] The configuration of the present disclosure is exemplified as follows. [1] a polygonal portion that reflects light emitted from the light source toward the detection portion and has a plurality of reflecting surfaces each having a different angle; a fixed portion fixed to a detection target object supported tiltably with respect to the light source and the detection portion; A multifaceted reflector comprising: [2] The multifaceted reflecting device according to [1], wherein the reflecting surface is hexagonal. [3] The polygonal reflecting device according to [1], wherein the polygonal portion has a spherical crown shape. [4] The multifaceted reflecting device according to [1], wherein the multifaceted portion is in a state where the plurality of planar portions are adjacent to each other. [5] The polygonal reflecting device according to [1], wherein the polygonal portions are arranged in a spherical zone. [6] The polygonal reflecting device according to [1], wherein the reflecting surfaces of the polygonal portion are arranged in a straight line at equal angles. [Explanation of symbols]

[0077] 1 Light source device 2. Scanner device 3 Deflection control device 4. Tilt detection device 5 Yoke member 6 Deflection member 7 Multifaceted reflector 11 Control section 12 Distance measuring optical system 13 Optical system driver circuit 14 Scanner device driver circuit 15 Angle sensor circuit 41 Light source 42 First Lens 43 Detection circuit board 44 Beam Splitter 45 Aperture plate 46 Second Lens 51 First York 52 Second York 53 First arm member 54 Second arm member 55 Base member 55-1 First base member 55-2 Second base member 55a Side edge 61 Reflector 62 Permanent Magnets 71 Fixed part 72 Multifaceted part 72A~72D Multifaceted part 431 Detection unit 432 Light receiving part 531 Torso 531a End 532 Protrusion 532a First end 533 York Coil 541 Torso 541a End 542 Protrusion 542a Second end 543 Yoke Coil 551 Notch 551a Inner surface 553, 554 Opening 611 Reflector 711 Base 711a Recess 711b Recess 712 Foundation part 713, 713D core 713a Tip surface 713b Concave surface 721 Reflective surface 721A~D Reflective surface 721a~d Reflective surface B, C, L optical axis C1 First magnetic path C2 Second magnetic path D1 First direction D2 Second direction Dx X-axis direction Dy Y-axis direction G Gap L1, L11, L12, L2 laser light L2a~L2d reflected light L2b, L2c laser light L3 reflected light L optical axis O reference point P axis Q Rotation center point R angle S reference line

Claims

1. a polygonal portion that reflects light emitted from the light source toward the detection portion and has a plurality of reflecting surfaces each having a different angle; a fixed portion fixed to a detection target object supported tiltably with respect to the light source and the detection portion; A multifaceted reflector comprising:

2. 2. The multifaceted reflector of claim 1, wherein said reflecting surface is hexagonal.

3. 2. The polygonal reflector according to claim 1, wherein said polygonal portion has a spherical crown shape.

4. 2. The polygonal reflector according to claim 1, wherein the polygonal portion has a plurality of the reflecting surfaces adjacent to each other.

5. 2. The polygonal reflector according to claim 1, wherein the polygonal portions are arranged in a spherical zone.

6. 2. The polygonal reflector according to claim 1, wherein the polygonal portion has the reflecting surfaces arranged in a straight line at equal angles.

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