Light deflector and optical scanner

Abstract

To provide a light deflector and an optical scanner for suppress the distortion of a pattern shape of reflection point of an object.SOLUTION: An optical scanner 10 having a light deflector 20 comprises a reflection part 30 for reflecting light from a light source 160, and a diffraction part 40 for diffracting the light reflected by the reflection part 30. The reflection part 30 causes a first incidence angle representing the incidence angle of light entering the diffraction part 40 in the periphery of a drive shaft Od to change by drive. The diffraction part 40 causes an angle θo1 of light emitted from the diffraction part 40 in the periphery of an axis X orthogonal to a direction heading from the drive shaft Od and the reflection part 30 toward the diffraction part 40 to change when the wavelength of light entering the diffraction part 40 changes. The angle of light emitted from the diffraction part 40 in the periphery of the drive shaft Od changes as the first incidence angle changes, and a second incidence angle θi2 representing the incidence angle of light entering the diffraction part 40 in the periphery of the axis X is maintained by being driven centering on the drive shaft Od together with the reflection part 30.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an optical deflector and an optical scanning device. [Background technology]

[0002] Conventionally, as described in Patent Document 1, a LIDAR system including a motor, a laser light source configured to generate an optical beam, and a deflector including a plurality of facets is known. In this LIDAR system, a first facet of the plurality of facets has a facet normal direction. Also, the deflector is coupled to the motor and configured to rotate about a rotation axis to deflect the optical beam from the laser light source. Note that LIDAR is an abbreviation for Light Detection and Ranging / Laser Imaging Detection and Ranging. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-510039 Summary of the Invention [Problem to be solved by the invention]

[0004] In the LIDAR system described in Patent Document 1, the rotation of the deflector changes the angle of the light reflected by the deflector around the axis of rotation, as well as the angle of the light reflected by the deflector around the axis extending in a direction perpendicular to the axis of rotation and the facet normal. This changes the angle of the light emitted from the deflector around the axis extending in a direction perpendicular to the axis of rotation and the facet normal. Therefore, when the light from the deflector is applied to a plane, the pattern shape of the reflection points on the plane formed as the deflector rotates is distorted. Therefore, for example, in the LIDAR system described in Patent Document 1, the accuracy of identifying the shape of an object by applying the light from the deflector to the object decreases.

[0005] An object of the present disclosure is to provide an optical deflector and an optical scanning device that suppress distortion of the pattern shape of reflection points on an object. [Means for solving the problem]

[0006] The invention described in claim 1 is an optical deflector that is driven to either rotate or swing around a drive shaft (Od) by the drive of a power source (12), and includes a reflecting section (30) that reflects light from a light source (160), and a diffractive section (40) that diffracts the light reflected by the reflecting section to emit light at an angle according to the wavelength of the incident light, and when the reflecting section is driven, a first incident angle (θi1), which is the angle of incidence of light incident on the diffractive section from the reflecting section around the drive shaft, is changed, and when the wavelength of light incident on the diffractive section from the reflecting section changes, the diffractive section changes the first incident angle (θi1). The optical deflector changes a first exit angle (θo1), which is the angle of light emitted from the diffraction unit around an axis (X) that extends in a direction perpendicular to the direction in which the drive axis extends and a direction perpendicular to the drive axis and perpendicular to one direction from the reflection unit to the diffraction unit; by changing the first incident angle, a second exit angle (θo2), which is the angle of light emitted from the diffraction unit around the drive axis, changes; and by driving together with the reflection unit around the drive axis, the optical deflector maintains a second incident angle (θi2), which is the angle of light incident on the diffraction unit from the reflection unit around the axis (X) that extends in the perpendicular direction.

[0007] The invention described in claim 8 is an optical scanning device comprising: a power source (12); a light source (160); an optical deflector (20) that is driven by the power source to either rotate or swing around a drive axis (Od) and has a reflecting section (30) that reflects light from the light source; and a diffraction section (40) that diffracts the light reflected by the reflecting section to emit light at an angle corresponding to the wavelength of the incident light; and a light receiving element (164) that receives light reflected from the diffraction section by an object via the diffraction section and the reflecting section, and the reflecting section is driven to receive a first incident angle (θ i1), and when the wavelength of light incident on the diffraction unit from the reflecting unit changes, the diffraction unit changes a first exit angle (θo1), which is the angle of light emitted from the diffraction unit around an axis (X) extending in a direction perpendicular to the direction in which the drive axis extends and a direction perpendicular to the drive axis and from the reflecting unit to the diffraction unit; the change in the first entrance angle changes a second exit angle (θo2), which is the angle of light emitted from the diffraction unit around the drive axis; and by driving together with the reflecting unit around the drive axis, the second entrance angle (θi2), which is the angle of light incident on the diffraction unit from the reflecting unit around the axis (X) extending in the perpendicular direction, is maintained.

[0008] As a result, even if the reflecting section is driven, the second incident angle is maintained. Therefore, the first exit angle does not change due to the driving of the reflecting section. Therefore, distortion of the pattern shape of the reflection points on the object is suppressed.

[0009] The reference symbols in parentheses attached to each component indicate an example of the correspondence between the component and specific components described in the embodiments described below. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a configuration diagram of an optical scanning device having an optical deflector according to a first embodiment. [Diagram 2] View from II in Figure 1. [Diagram 3] FIG. 2 is a diagram showing a light source of an optical integrated circuit in an optical scanning device. [Figure 4] FIG. 2 is a diagram showing a waveguide of an optical integrated circuit in an optical scanning device. [Diagram 5] FIG. 2 is a diagram showing a diffractive portion of an optical deflector. [Figure 6] FIG. [Figure 7] FIG. 13 is a diagram showing a state where a reflecting portion of the optical deflector is rotated. [Figure 8] 4 is a diagram showing a pattern of reflection points when light from a diffractive portion is applied to a flat surface. [Figure 9] 13 is a diagram showing a pattern of reflection points when light is applied to a flat surface by a deflector of a comparative example. [Figure 10] FIG. 13 is a diagram showing a modified optical deflector. [Figure 11] FIG. 13 is a diagram showing a modified optical deflector. [Figure 12] FIG. 13 is a diagram showing a diffractive portion of a modified optical deflector. [Figure 13] FIG. 13 is a diagram showing a diffractive portion of a modified optical deflector. [Figure 14] FIG. 13 is a diagram showing a light source of an optical integrated circuit in an optical scanning device of a modified example. [Figure 15] 10A to 10C are diagrams for explaining the operation of the optical scanning device of the modified example. [Figure 16] 13 is a diagram showing a waveguide and a mirror of an optical integrated circuit in an optical scanning device of a modified example. [Figure 17] 13 is a diagram showing a waveguide and a mirror of an optical integrated circuit in an optical scanning device of a modified example. [Figure 18] 13 is a diagram showing a waveguide and a microlens of an optical integrated circuit in an optical scanning device of a modified example. [Figure 19] FIG. 11 is a cross-sectional view showing the configuration of an optical scanning device having an optical deflector according to a second embodiment. [Figure 20] FIG. 11 is a configuration diagram of an optical scanning device having an optical deflector according to a third embodiment. [Figure 21] FIG. 13 is a configuration diagram of an optical scanning device having an optical deflector according to a fourth embodiment. [Figure 22] FIG. 13 is a configuration diagram of an optical scanning device having an optical deflector according to a fifth embodiment. [Figure 23] FIG. 13 is a configuration diagram of an optical scanning device having an optical deflector according to a sixth embodiment. [Figure 24] 13A and 13B are diagrams showing an incidence adjustment element of a modified optical deflector. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals, and the description thereof will be omitted.

[0012] (First embodiment) In an optical scanning device having the optical deflector of this embodiment, distortion of the pattern shape of reflection points on an object is suppressed. This optical scanning device is used, for example, in a LIDAR.

[0013] Specifically, as shown in FIGS. 1 and 2, an optical scanning device 10 includes a power source 12, a semiconductor substrate 14, an optical integrated circuit 16, and an optical deflector 20.

[0014] The power source 12 is a motor or the like, and drives around a drive shaft Od. Here, "drive" refers to either rotation or oscillation.

[0015] The semiconductor substrate 14 is made of, for example, silicon etc. The optical integrated circuit 16 is formed on the semiconductor substrate 14. The optical integrated circuit 16 also has a light source 160, a waveguide 162 and a light receiving element 164.

[0016] A plurality of light sources 160 are arranged as shown in Fig. 3. Furthermore, the light source 160 emits light of different wavelength bands Δλ1, Δλ2, Δλ3, and Δλ4 in a wavelength band used for optical communication, for example, S-band or C-band, via a waveguide 162 as shown in Fig. 4. In Fig. 3, the light of Δλ1 is shown by a solid line, the light of Δλ2 is shown by a dashed line, the light of Δλ3 is shown by a dashed line, and the light of Δλ4 is shown by a dashed line.

[0017] Returning to FIG. 1, the light receiving element 164 is a photodiode, a phototransistor, or the like, and receives light that is irradiated from the light source 160 via the optical deflector 20 (described later) and reflected by an object.

[0018] The optical deflector 20 deflects light from the light source 160 and irradiates an object with the deflected light. Specifically, the optical deflector 20 has a first holding section 21, a second holding section 22, a reflecting section 30, a diffractive section 40, and a light transmitting section 50.

[0019] The first holding portion 21 is made of metal, resin, or the like. Furthermore, as shown in Figs. 1 and 2, the first holding portion 21 is formed, for example, in a regular hexagonal pyramid shape. Furthermore, a hole (not shown) is formed in the first holding portion 21. A part of the power source 12 is inserted into the hole of the first holding portion 21. As a result, the first holding portion 21, together with the power source 12, is driven about the drive shaft Od.

[0020] The second holding portion 22 is formed of metal, resin, or the like. The second holding portion 22 is formed, for example, in a regular hexagonal plate shape perpendicular to the drive axis Od. The second holding portion 22 is connected to the first holding portion 21 in the direction of the drive axis Od. Therefore, the second holding portion 22 drives around the drive axis Od together with the power source 12 and the first holding portion 21.

[0021] The reflecting unit 30 is a mirror or the like, and reflects light from the light source 160. The reflecting unit 30 is formed on the side surface of the first holding unit 21 by deposition or the like. As a result, the reflecting unit 30 drives together with the power source 12, the first holding unit 21, and the second holding unit 22 about the drive axis Od. The reflecting unit 30 has a side surface shape of a regular hexagonal pyramid.

[0022] The diffraction unit 40 is a diffraction grating having a square groove as shown in FIG. 5, and the outer shape of the diffraction unit 40 is a regular hexagonal tube extending in the direction of the drive axis Od as shown in FIG. 1 and FIG. 2. The diffraction unit 40 is disposed on the outside of the reflecting unit 30 in the direction perpendicular to the drive axis Od. The diffraction unit 40 has a shape corresponding to the shape of the reflecting unit 30, and is a regular hexagon here. The diffraction unit 40 diffracts the light reflected by the reflecting unit 30. As a result, the diffraction unit 40 emits light at an angle according to the wavelength of the light incident on the diffraction unit 40. The diffraction unit 40 is connected to the second holding unit 22 in the direction of the drive axis Od. Therefore, the diffraction unit 40 drives the power source 12, the first holding unit 21, the second holding unit 22, and the reflecting unit 30 around the drive axis Od.

[0023] The light transmitting section 50 has a first transmitting section 51 and a second transmitting section 52. The first transmitting section 51 is formed between the light source 160 and the reflecting section 30, and is defined as a space here. The first transmitting section 51 transmits light traveling from the light source 160 toward the reflecting section 30. The second transmitting section 52 is formed between the reflecting section 30 and the diffractive section 40, and is defined as a space here. The second transmitting section 52 transmits light traveling from the reflecting section 30 toward the diffractive section 40.

[0024] The optical scanning device 10 having the optical deflector 20 of the first embodiment is configured as described above. Next, the operation of the optical scanning device 10 when used in a LIDAR will be described.

[0025] Here, the following terms are defined to explain the operation of the optical scanning device 10. As shown in FIG. 1 and FIG. 2, a Cartesian coordinate system based on the center of the optical deflector 20 is defined as a deflector coordinate system. The X-axis, Y-axis, and Z-axis in the deflector coordinate system are mutually orthogonal. The deflector coordinate system is expressed as a right-handed system. The Y-axis is an axis parallel to the drive axis Od. The Z-axis is an axis that is orthogonal to the drive axis Od and extends in one direction from the reflecting unit 30 toward the diffractive unit 40. The X-axis is an axis that extends in a direction orthogonal to the drive axis Od and the above-mentioned one direction. Furthermore, the angle of incidence of light incident from the reflecting unit 30 to the diffractive unit 40 around the drive axis Od or the Y-axis is defined as a first angle of incidence θi1. The angle of incidence of light incident from the reflecting unit 30 to the diffractive unit 40 around the X-axis is defined as a second angle of incidence θi2. The angle of light emitted from the diffractive unit 40 around the X-axis is defined as a first emission angle θo1. The angle of the light emitted from the diffraction section 40 around the drive axis Od or the Y axis is defined as the second exit angle θo2. Here, the first incidence angle θi1, the second incidence angle θi2, the first exit angle θo1, and the second exit angle θo2 are angles based on the Z axis. Furthermore, the shape of the grating section of the diffraction section 40 is adjusted so that the first incidence angle θi1 and the second exit angle θo2 are the same. In addition, in FIG. 1 and FIG. 2, the path of the light is typically indicated by a two-dot chain line.

[0026] Then, as shown in Fig. 6, light of a plurality of wavelength bands is emitted from light source 160. The light emitted from light source 160 passes through first transmission section 51 and is reflected by reflection section 30. The light reflected by reflection section 30 passes through second transmission section 52 and is incident on diffraction section 40. The light incident on diffraction section 40 is diffracted and emitted from diffraction section 40. Note that in Fig. 6, the paths of light having different wavelengths are diagrammatically indicated by solid lines, dashed lines, one-dot chain lines, and two-dot chain lines.

[0027] Here, the groove interval of the diffractive section 40 is d. The wavelength of light incident on the diffractive section 40 is λ. The refractive index of the medium of the diffractive section 40 is n. In this case, the first exit angle θo1 is expressed by the following relational expression (1).

[0028]

number

[0029] Furthermore, for each wavelength of light emitted from the light source 160, the light is emitted from the diffraction section 40 at a first exit angle θo1 according to the wavelength of the light incident on the diffraction section 40. Therefore, when the wavelength of the light incident on the diffraction section 40 from the reflection section 30 changes, the diffraction section 40 changes the first exit angle θo1.

[0030] Furthermore, the light emitted from the diffraction section 40 is reflected by an object (not shown). The light reflected by the object passes through the diffraction section 40, the second transmission section 52, the reflection section 30, and the first transmission section 51, and is received by the light receiving element 164. From the intensity of the light received by the light receiving element 164, a calculation device (not shown) calculates the relative distance, relative speed, and direction from the optical scanning device 10 to the object.

[0031] As shown in FIG. 7, the power source 12 is driven to drive the reflecting unit 30 around the drive axis Od. Furthermore, the reflecting unit 30 has a side shape of a regular hexagonal pyramid. As a result, the direction of the light hitting the reflecting unit 30 changes. Therefore, the first incident angle θi1 changes. Therefore, the second exit angle θo2 changes. In FIG. 7, the light path is shown typically by a two-dot chain line.

[0032] At this time, the diffraction unit 40 rotates around the drive axis Od together with the reflecting unit 30. As a result, the diffraction unit 40 maintains the second incident angle θi2. Therefore, the first exit angle θo1 is maintained. Therefore, as shown in FIG. 8, when light from the diffraction unit 40 is applied to a plane S perpendicular to the Z axis, distortion of the pattern shape of the first reflection point Pr1 and the second reflection point Pr2 on the plane S is suppressed. The first reflection point Pr1 is a reflection point on the plane S that changes due to the rotation of the reflecting unit 30. The second reflection point Pr2 is a reflection point on the plane S that changes depending on the wavelength of the light incident on the diffraction unit 40.

[0033] Furthermore, the shapes and positional relationships of the reflecting section 30 and the diffractive section 40 are adjusted so that the first parallel direction Dp1 in which the first reflection points Pr1 are arranged and the second parallel direction Dp2 in which the second reflection points Pr2 are arranged are perpendicular to each other.

[0034] As described above, the pattern shape of the reflection points of the object is obtained from the rotation of the reflecting section 30 and the change in the wavelength incident on the diffractive section 40. Therefore, the shape of the object is identified by a calculation device (not shown) from the intensity of the light received by the light receiving element 164, the first exit angle θo1, and the second exit angle θo2.

[0035] The operation of the optical scanning device 10 is as described above. Next, a description will be given of how the optical scanning device 10 having the optical deflector 20 suppresses distortion of the pattern shape of reflection points on an object.

[0036] Here, in the LIDAR system described in Patent Document 1, the deflector rotates. This causes a change in the angle of the light reflected by the deflector around the axis of rotation, as well as a change in the angle of the light reflected by the deflector around an axis extending in a direction perpendicular to the axis of rotation and the facet normal. This causes a change in the angle of the light emitted from the deflector around an axis extending in a direction perpendicular to the axis of rotation and the facet normal. Therefore, when the light from the deflector is applied to a flat surface, the pattern shape of the reflection points on the flat surface formed as the deflector rotates is distorted, as shown in FIG. 9.

[0037] In contrast, in the optical scanning device 10 having the optical deflector 20 of this embodiment, the diffraction unit 40 is driven about the drive axis Od together with the reflection unit 30. As a result, the diffraction unit 40 maintains the second incident angle θi2 around the X-axis.

[0038] As a result, the second incident angle θi2 is maintained even when the reflecting unit 30 is driven. Therefore, the first exit angle θo1 does not change due to the driving of the reflecting unit 30. Therefore, as shown in FIG. 8, distortion of the pattern shape of the reflection points of the object is suppressed.

[0039] Furthermore, the optical scanning device 10 having the optical deflector 20 of the first embodiment has the following advantages.

[0040] [1] The first parallel direction Dp1 is perpendicular to the second parallel direction Dp2. The first parallel direction Dp1 is the direction in which the first reflection points Pr1 are arranged. The second parallel direction Dp2 is the direction in which the second reflection points Pr2 are arranged.

[0041] This makes it easier to express the pattern shape of the reflection points of the object in two dimensions, which makes it easier to identify the shape of the object using the light emitted from the diffractive section 40, compared to a case in which the first parallel direction Dp1 and the second parallel direction Dp2 are not perpendicular to each other.

[0042] (Variation 1) In the first embodiment, the shape of the optical deflector 20 when viewed from the direction of the drive axis Od is a regular hexagon, but the shape is not limited to this.

[0043] As shown in Fig. 10, the shape of the optical deflector 20 may be a square shape. Specifically, the first holding portion 21 is formed in a square truncated pyramid shape. The second holding portion 22 is formed in a square plate shape. The reflecting portion 30 has a side shape of a square truncated pyramid. The outer shape of the diffractive portion 40 is a square cylinder extending in the direction of the drive axis Od.

[0044] Also, as shown in FIG. 11, the shape of the optical deflector 20 may be a regular pentagonal shape. Specifically, the first holding part 21 is formed in a regular pentagonal pyramid shape. The second holding part 22 is formed in a regular pentagonal plate shape. The reflecting part 30 has a side shape of a regular pentagonal pyramid. The outer shape of the diffraction part 40 is a regular pentagonal cylinder extending in the direction of the drive axis Od. Furthermore, the shape of the optical deflector 20 when viewed from the direction of the drive axis Od may be a polygonal shape, an ellipse shape, or the like. Even if done as described above, the same effects as those of the first embodiment can be achieved.

[0045] (Variation 2) In the first embodiment, the shape of the grooves in the diffractive section 40 is a quadrangle, but the shape is not limited to this.

[0046] As shown in FIG. 12, the shape of the grooves of the diffractive section 40 is a sawtooth shape, and the diffractive section 40 may be a blazed diffraction grating.

[0047] 13, the diffractive section 40 may be a VPH diffraction grating in which the refractive index of the medium of the diffractive section 40 is modulated in a sinusoidal manner. VPH stands for Volume Phase Holographic. Even in this case, the same effects as those of the first embodiment can be obtained.

[0048] (Variation 3) In the first embodiment, a plurality of light sources 160 are arranged, and each light source 160 emits light of a respective wavelength.

[0049] In contrast, as shown in Fig. 14, there may be only one light source 160. In this case, the light source 160 emits light of a single wavelength, and then emits light of a single wavelength different from the emitted light. In Fig. 14, the light that is first emitted by the light source 160 is shown typically by a solid line. The light that is later emitted by the light source 160 is shown typically by a dashed line.

[0050] Also, as shown in Fig. 15, at least one of the multiple light sources 160 may be used for FMCW. FMCW is an abbreviation of Frequency Modulated Continuous Wave radar. Furthermore, each of the multiple light sources 160 may change the wavelength in a different wavelength band. Even in the above case, the same effect as the first embodiment is obtained.

[0051] (Variation 4) In the first embodiment, the light source 160 emits light through a waveguide 162 .

[0052] On the other hand, the light source 160 may emit light through a waveguide 162 and a light source mirror 166 facing the waveguide 162, as shown in Fig. 16. The light source 160 may also emit light through a waveguide 162 and a light source mirror 166 embedded in the optical integrated circuit 16, as shown in Fig. 17. Furthermore, the light source 160 may emit light through a waveguide 162 and a microlens 168, as shown in Fig. 18. Even in the above-mentioned case, the same effects as those of the first embodiment can be obtained.

[0053] Second embodiment The second embodiment differs from the first embodiment in the form of the optical deflector 20. Other than this, the second embodiment is similar to the first embodiment.

[0054] 19, the optical deflector 20 does not have a first holding portion 21 and a second holding portion 22. Also, the light transmitting portion 50 is formed of a light transmitting resin or the like. Furthermore, the reflecting portion 30, the diffractive portion 40, and the light transmitting portion 50 are integrated together.

[0055] The optical scanning device 10 having the optical deflector 20 of the second embodiment is configured as described above. The second embodiment also provides the same effects as the first embodiment. The second embodiment also provides the following effects.

[0056] [2] The reflecting section 30, the diffractive section 40, and the light transmitting section 50 are integrated. This allows the light transmitting section 50, the reflecting section 30, and the diffractive section 40 to be molded integrally. This makes it easier to manufacture the light deflector 20 compared to when the light deflector 20 has the first holding section 21 and the second holding section 22.

[0057] Third embodiment In the third embodiment, as shown in Fig. 20, the optical deflector 20 further includes a beam adjusting element 60. The rest is the same as in the first embodiment.

[0058] The beam adjusting element 60 is disposed between the reflecting section 30 and the diffracting section 40. Furthermore, the beam adjusting element 60 has a plurality of lenses, so that the diffracting section incident beam diameter Wi is larger than the reflected beam diameter Wr. In FIG. 20, the light from the light source 160 is shown in a dot pattern and a two-dot chain line. Furthermore, the diffracting section incident beam diameter Wi is the beam diameter of the light incident on the diffracting section 40. The reflected beam diameter Wr is the beam diameter of the light reflected by the reflecting section 30. Furthermore, the beam diameter is the diameter along a specific line perpendicular to and intersecting the beam axis. Moreover, the beam diameter is measured using D4σ, knife edge, Gaussian beam, FWHM, D86, and the like. FWHM is an abbreviation for Full Width at Half Maximum.

[0059] The optical scanning device 10 having the optical deflector 20 of the third embodiment is configured as described above. The third embodiment also provides the same effects as the first embodiment. The third embodiment also provides the following effects.

[0060] [3] The optical deflector 20 further includes a beam adjusting element 60 that makes the diameter Wi of the beam incident on the diffractive portion larger than the diameter Wr of the reflected beam.

[0061] As a result, the light reflected by the reflecting section 30 is more likely to enter the diffractive section 40. Therefore, the range of light emitted from the diffractive section 40 is expanded. Therefore, the light emitted from the diffractive section 40 is more likely to be reflected by an object. Therefore, the intensity of the light reflected by the object increases. As a result, the light reflected by the object is more likely to be received by the light receiving element 164 via the diffractive section 40 and the reflecting section 30.

[0062] (Fourth embodiment) In the fourth embodiment, as shown in Fig. 21, the function of the beam adjusting element 60 is different from that in the third embodiment.

[0063] The beam adjusting element 60 makes the diffractive portion incident beam diameter Wi smaller than the reflected beam diameter Wr, instead of making the diffractive portion incident beam diameter Wi larger than the reflected beam diameter Wr. In addition, in Fig. 21, the light from the light source 160 is diagrammatically shown by a dot pattern and a two-dot chain line.

[0064] The optical scanning device 10 having the optical deflector 20 of the fourth embodiment is configured as described above. The fourth embodiment also provides the same effects as the first embodiment. The fourth embodiment also provides the following effects.

[0065] [4] The optical deflector 20 further includes a beam adjusting element 60 that adjusts the diameter Wi of the beam incident on the diffractive portion to be smaller than the diameter Wr of the reflected beam.

[0066] This makes the beam diameter of the light emitted from the diffractive section 40 relatively small, thereby increasing the resolution for object detection using the light emitted from the diffractive section 40.

[0067] Fifth embodiment In the fifth embodiment, as shown in Fig. 22, the optical deflector 20 further includes an emission adjustment element 70. The rest is the same as in the first embodiment.

[0068] The emission adjustment element 70 is disposed on the outside in the direction perpendicular to the drive axis Od relative to the diffraction section 40. Furthermore, the emission adjustment element 70 has a prism or the like, so that the light emitted from the diffraction section 40 is emitted at an emission angle different from the first emission angle θo1.

[0069] The optical scanning device 10 having the optical deflector 20 of the fifth embodiment is configured as described above. The fifth embodiment also provides the same effects as the first embodiment. The fifth embodiment also provides the following effects.

[0070] [5] The optical deflector 20 further includes an emission adjustment element 70 that emits the light emitted from the diffraction section 40 at an emission angle different from the first emission angle θo1.

[0071] This allows the first emission angle θo1 to be adjusted, making it possible to adjust the scanning position of the optical scanning device 10.

[0072] Sixth embodiment In the sixth embodiment, as shown in Fig. 23, the optical deflector 20 further includes an incidence adjustment element 80. The rest is the same as in the first embodiment.

[0073] The incidence adjustment element 80 is disposed between the light source 160 and the reflector 30. The incidence adjustment element 80 has a plurality of collimator lenses, and thereby collimates the light from the light source 160. In FIG. 23, the light from the light source 160 is shown typically by a dot pattern and a two-dot chain line. Furthermore, the collimated light is a light in a state where all the light rays in the beam are parallel to all the other light rays. In addition, the parallelism in the collimated light includes the manufacturing error range.

[0074] The optical scanning device 10 having the optical deflector 20 of the sixth embodiment is configured as described above. The sixth embodiment also provides the same effects as the first embodiment. The sixth embodiment also provides the following effects.

[0075] [6] The optical deflector 20 further includes an incidence adjustment element 80 for collimating the light from the light source 160 .

[0076] As a result, the light emitted from the diffraction section 40 also becomes collimated light. Therefore, compared to a case where the light emitted from the diffraction section 40 spreads radially, the light emitted from the diffraction section 40 is prevented from spreading or converging. Therefore, the light emitted from the diffraction section 40 can easily reach far away.

[0077] (Modification) In the sixth embodiment, the incidence adjusting element 80 has a plurality of collimator lenses to collimate the light from the light source 160, but the present invention is not limited to this.

[0078] The incidence adjustment element 80 may have a single lens or the like to collimate the light from the light source 160, as shown in Fig. 24. In Fig. 24, the light from the light source 160 is diagrammatically shown by a dot pattern and a two-dot chain line.

[0079] (Other embodiments) The present disclosure is not limited to the above-described embodiments, and appropriate modifications can be made to the above-described embodiments. Furthermore, in each of the above-described embodiments, it goes without saying that the elements constituting the embodiments are not necessarily essential, except in cases where they are particularly clearly stated as essential or where they are clearly considered essential in principle.

[0080] The above-described embodiments and modifications may be combined as appropriate.

[0081] (In view of the present disclosure) [Point 1] 1. An optical deflector, comprising: a reflecting section (30) that is driven by a power source (12) to either rotate or swing about a drive shaft (Od) and that reflects light from a light source (160); a diffraction section (40) that diffracts the light reflected by the reflection section to emit the light at an angle according to the wavelength of the incident light; Equipped with The reflecting portion is By driving, a first incident angle (θi1) which is an incident angle of light incident on the diffraction section from the reflection section around the drive shaft is changed, The diffractive portion is when the wavelength of the light incident on the diffraction section from the reflection section changes, a first exit angle (θo1) is changed, which is an angle of the light exiting from the diffraction section around an axis (X) extending in a direction perpendicular to a direction in which the drive shaft extends and a direction perpendicular to the drive shaft and perpendicular to one direction from the reflection section toward the diffraction section; A second exit angle (θo2), which is an angle of light exiting from the diffraction section around the drive shaft, is changed by changing the first incident angle, An optical deflector that maintains a second incident angle (θi2), which is the incident angle of light incident from the reflecting unit to the diffractive unit around an axis (X) extending in the perpendicular direction, by being driven together with the reflecting unit around the drive axis. [Point 2] a light transmitting section (50) including a first transmitting section (51) formed between the light source and the reflecting section and transmitting light proceeding from the light source to the reflecting section, and a second transmitting section (52) formed between the reflecting section and the diffractive section and transmitting light proceeding from the reflecting section to the diffractive section, The optical deflector according to claim 1, wherein the reflecting section, the diffractive section and the light transmitting section are integrated together. [Point 3] The optical deflector according to aspect 1 or 2, further comprising a beam adjusting element (60) for making a beam diameter (Wi) of light incident on the diffraction portion larger than a beam diameter (Wr) of light reflected by the reflection portion. [Point 4] The optical deflector according to aspect 1 or 2, further comprising a beam adjusting element (60) for making a beam diameter (Wi) of light incident on the diffraction portion smaller than a beam diameter (Wr) of light reflected by the reflection portion. [Point 5] 5. The optical deflector according to any one of Aspects 1 to 4, further comprising an exit adjustment element (70) that outputs the light exiting from the diffraction portion at an exit angle different from the first exit angle. [Point 6] 6. The optical deflector according to any one of Aspects 1 to 5, further comprising an incidence adjustment element (80) for collimating the light from the light source. [Point 7] An optical deflector described in any one of viewpoints 1 to 6, wherein, when light from the diffraction section is applied to a plane (S) perpendicular to the one direction, a direction (Dp1) in which first reflection points (Pr1) on the plane are arranged, which changes by driving the reflection section, is perpendicular to a direction (Dp2) in which second reflection points (Pr2) on the plane are arranged, which changes depending on the wavelength of light incident on the diffraction section. [Point 8] An optical scanning device, comprising: A power source (12); A light source (160); an optical deflector (20) that is driven by the power source to either rotate or swing about a drive shaft (Od), and that has a reflecting section (30) that reflects light from the light source, and a diffracting section (40) that diffracts the light reflected by the reflecting section to emit light at an angle corresponding to the wavelength of the incident light; a light receiving element (164) that receives light reflected from an object via the diffraction section and the reflection section; Equipped with The reflecting portion is By driving, a first incident angle (θi1) which is an incident angle of light incident on the diffraction section from the reflection section around the drive shaft is changed, The diffractive portion is when the wavelength of the light incident on the diffraction section from the reflection section changes, a first exit angle (θo1) is changed, which is an angle of the light exiting from the diffraction section around an axis (X) extending in a direction perpendicular to a direction in which the drive shaft extends and a direction perpendicular to the drive shaft and perpendicular to one direction from the reflection section toward the diffraction section; A second exit angle (θo2), which is an angle of light exiting from the diffraction section around the drive shaft, is changed by changing the first incident angle, An optical scanning device that maintains a second incident angle (θi2), which is the incident angle of light incident from the reflecting unit to the diffractive unit around an axis (X) extending in the perpendicular direction, by driving together with the reflecting unit around the drive axis. [Explanation of symbols]

[0082] 10 Optical scanning device 12 Power source 14 Semiconductor substrate 16 Optical Integrated Circuits 20 Optical deflector 30 Reflector 40 Diffraction section 160 light source 162 Waveguide 164 Photodetector

Claims

1. 1. An optical deflector, comprising: a reflecting section (30) that is driven by a power source (12) to either rotate or swing about a drive shaft (Od) and that reflects light from a light source (160); a diffraction section (40) that diffracts the light reflected by the reflection section to emit the light at an angle according to the wavelength of the incident light; Equipped with The reflecting portion is By driving, a first incident angle (θi1) which is an incident angle of light incident on the diffraction section from the reflection section around the drive axis is changed, The diffractive portion is when the wavelength of the light incident on the diffraction section from the reflection section changes, a first exit angle (θo1) is changed, which is an angle of the light exiting from the diffraction section around an axis (X) extending in a direction perpendicular to the extension direction of the drive shaft and a direction perpendicular to the drive shaft and perpendicular to one direction from the reflection section toward the diffraction section; A second exit angle (θo2), which is an angle of light exiting from the diffraction section around the drive shaft, is changed by changing the first incident angle, An optical deflector that maintains a second incident angle (θi2), which is the angle of incidence of light incident from the reflecting portion to the diffractive portion around an axis (X) extending in the perpendicular direction, by driving the reflecting portion together with the driving axis.

2. a light transmitting section (50) including a first transmitting section (51) formed between the light source and the reflecting section and transmitting light from the light source toward the reflecting section, and a second transmitting section (52) formed between the reflecting section and the diffractive section and transmitting light from the reflecting section toward the diffractive section, 2. The optical deflector according to claim 1, wherein the reflecting portion, the diffractive portion and the light transmitting portion are integrated together.

3. 3. The optical deflector according to claim 1, further comprising a beam adjusting element (60) for making a beam diameter (Wi) of light incident on the diffraction portion larger than a beam diameter (Wr) of light reflected by the reflection portion.

4. 3. The optical deflector according to claim 1, further comprising a beam adjusting element (60) for making a beam diameter (Wi) of light incident on the diffraction portion smaller than a beam diameter (Wr) of light reflected by the reflection portion.

5. 3. The optical deflector according to claim 1, further comprising an exit adjustment element (70) that outputs the light emitted from the diffraction portion at an exit angle different from the first exit angle.

6. 3. The optical deflector according to claim 1, further comprising an incidence adjustment element (80) for collimating the light from the light source.

7. An optical deflector as described in claim 1 or 2, wherein, when light from the diffraction section is applied to a plane (S) perpendicular to the one direction, a direction (Dp1) in which first reflection points (Pr1) on the plane are arranged and which changes when the reflection section is driven is perpendicular to a direction (Dp2) in which second reflection points (Pr2) on the plane are arranged and which changes depending on the wavelength of light incident on the diffraction section.

8. An optical scanning device, comprising: A power source (12); and A light source (160); an optical deflector (20) that is driven by the power source to either rotate or swing about a drive shaft (Od) and has a reflecting section (30) that reflects light from the light source, and a diffracting section (40) that diffracts the light reflected by the reflecting section to emit light at an angle corresponding to the wavelength of the incident light; A light receiving element (164) that receives light reflected from an object via the diffraction section and the reflection section; Equipped with The reflecting portion is By driving, a first incident angle (θi1) which is an incident angle of light incident on the diffraction section from the reflection section around the drive axis is changed, The diffractive portion is when the wavelength of the light incident on the diffraction section from the reflection section changes, a first exit angle (θo1) is changed, which is an angle of the light exiting from the diffraction section around an axis (X) extending in a direction perpendicular to the extension direction of the drive shaft and a direction perpendicular to the drive shaft and perpendicular to one direction from the reflection section toward the diffraction section; A second exit angle (θo2), which is an angle of light exiting from the diffraction section around the drive shaft, is changed by changing the first incident angle, An optical scanning device that maintains a second incident angle (θi2), which is the incident angle of light incident from the reflecting unit to the diffractive unit around an axis (X) extending in the perpendicular direction, by driving the reflecting unit around the drive axis.

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