JPWO2013080626A1 - Mirror actuator, beam irradiation device and laser radar - Google Patents

Abstract

A mirror actuator capable of applying a stable drag force to a mirror when the mirror is rotated, a beam irradiation device and a laser radar equipped with the mirror actuator are provided.
A mirror actuator includes an inner unit and an outer unit. The inner unit 10 is rotatably supported by the outer unit 20 by tilt shafts 25 and 26. When the inner unit 10 is rotated in the tilt direction from the tilt neutral position, the magnets for magnetic springs 252 and 262 fixed to the ends of the tilt shafts 25 and 26, and the tilt magnets 151 and 161 of the tilt coil units 22 and 23, During this period, a magnetic force is generated that pulls the inner unit 10 back to the tilt neutral position. When the mirror 123 rotates in the tilt direction, a drag force due to this magnetic force is applied to the inner unit 10.
[Selection] Figure 1

Description

  The present invention relates to a mirror actuator that rotates a mirror about two axes as a rotation axis, and a beam irradiation apparatus and a laser radar equipped with the mirror actuator.

  In recent years, laser radar has been used to monitor the status of a target area. In general, a laser radar scans a laser beam within a target area and detects the presence or absence of an object at each scan position from the presence or absence of reflected light at each scan position. Further, the distance to the object is detected based on the required time from the laser beam irradiation timing to the reflected light reception timing at each scan position.

  As an actuator for scanning a laser beam in a target area, for example, a moving coil type mirror actuator that rotates a mirror about two axes as rotation axes can be used (Patent Document 1). When this mirror actuator is used, the laser light is incident on the mirror from an oblique direction. When the mirror is rotated in the horizontal direction and the vertical direction using the two axes as rotation axes, the laser light is oscillated in the horizontal direction and the vertical direction in the target area.

JP 2009-14698 A

  In the above mirror actuator, in order to improve the controllability of the mirror, it is necessary to stabilize the drag applied to the mirror when the mirror is driven. For example, a spring member may be used as means for applying a drag force to the mirror. However, it is difficult to apply a certain drag force to the two rotating shafts by the spring member.

  The present invention has been made in view of such problems, and provides a mirror actuator capable of imparting a stable drag force to the mirror when the mirror rotates, a beam irradiation device equipped with the mirror actuator, and a laser radar. For the purpose.

  A first aspect of the present invention relates to a mirror actuator. A mirror actuator according to a first aspect is disposed on each of a support part, a movable part that holds a mirror and is rotatably supported by the support part, and the support part and the movable part. And a magnetic member for applying a magnetic force to the movable part to pull the movable part back to the set position when the is rotated from a predetermined setting position.

  The second aspect of the present invention relates to a beam irradiation apparatus. A beam irradiation apparatus according to a second aspect includes the mirror actuator according to the first aspect and a laser light source that supplies laser light to a mirror of the mirror actuator.

  The third aspect of the present invention relates to a laser radar. A laser radar according to a third aspect includes a mirror actuator according to the first aspect, a laser light source that supplies laser light to a mirror of the mirror actuator, and a light receiving unit that receives the laser light reflected from a target area. And a detection unit that detects an object in the target area based on an output from the light receiving unit.

  ADVANTAGE OF THE INVENTION According to this invention, the mirror actuator which can provide the stable drag with respect to a mirror at the time of rotation of a mirror, the beam irradiation apparatus and laser radar which mount this mirror actuator can be provided.

  The effects and significance of the present invention will become more apparent from the following description of embodiments. However, the embodiment described below is merely an example when the present invention is implemented, and the present invention is not limited to what is described in the following embodiment.

It is a figure which shows the disassembled perspective view of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the assembly process of the mirror actuator which concerns on embodiment. It is a figure which shows the mounting state of the magnet for magnetic springs which concerns on embodiment. It is a figure which shows the mirror actuator which concerns on embodiment. It is a figure which shows the effect | action at the time of rotation of the mirror actuator which concerns on embodiment. It is a figure which shows the structural example in the case of adjusting the magnetic force generate | occur | produced between the tilt magnet which concerns on embodiment, and the magnet for magnetic springs. It is a figure which shows the structure of the laser radar which concerns on embodiment. It is a figure explaining the structure and effect | action of the servo optical system which concerns on embodiment. It is a figure which shows the circuit structure of the laser radar which concerns on embodiment. It is a figure which shows the structure of the mirror actuator which concerns on the example of a change. It is a figure which shows the structure of the mirror actuator which concerns on the example of a change.

  FIG. 1 is an exploded perspective view of a mirror actuator 1 according to the present embodiment. As illustrated, the mirror actuator 1 includes an inner unit 10 and an outer unit 20.

  FIG. 2 is an exploded perspective view of the inner unit 10 of the mirror actuator 1. As illustrated, the inner unit 10 includes an inner unit frame 11, a pan shaft 12, pan magnet units 13, 14, tilt magnet units 15, 16, pan coil units 17, 18, and suspension wires 19a to 19d. I have.

  3A and 3B are perspective views when the inner unit frame 11 is viewed from the upper side and the lower side, respectively.

  The inner unit frame 11 is made of a frame member having a rectangular outline when viewed from the front. The inner unit frame 11 is made of a lightweight resin or the like. Further, the inner unit frame 11 has a symmetrical shape.

  A magnet mounting groove 11 a for mounting the pan magnet 131 is provided on the upper side surface of the inner unit frame 11. Screw holes 11b and 11c for fixing the tilt magnet holder 152 are formed in the magnet mounting groove 11a. Similarly, a magnet mounting groove 11d for mounting the pan magnet 141 is provided on the lower surface of the inner unit frame 11, and a screw hole 11e for fixing the pan magnet holder 142 is provided in the magnet mounting groove 11d. , 11f are formed. Further, a magnet mounting groove 11g for mounting the tilt magnet 151 is provided on the left side surface of the inner unit frame 11. Screw holes 11h and 11i for fixing the tilt magnet holder 152 are formed in the magnet mounting groove 11g. Similarly, a magnet mounting groove 11j for mounting the tilt magnet 161 is provided on the right side surface of the inner unit frame 11, and a screw hole 11k for fixing the tilt magnet holder 162 is provided in the magnet mounting groove 11j. 11l is formed.

  Further, the inner unit frame 11 is formed with shaft holes 11m arranged on the left and right and shaft holes 11n arranged on the top and bottom. The shaft hole 11m is disposed at the center position of the left and right side surfaces, and the shaft hole 11n is disposed at the center of the upper and lower side surfaces.

  Furthermore, a flange 11q is provided on the left end of the bottom surface of the inner unit frame 11. A convex portion 11r is formed on the back surface (downward direction) of the flange portion 11q. Similarly, a flange 11s is provided at the right end on the bottom surface of the inner unit frame 11, and a protrusion 11t is formed on the back surface (downward) of the flange 11s.

  FIG. 4 is a diagram illustrating a configuration of the pan shaft 12. 4A is a perspective view of the pan shaft 12 viewed from the front side, and FIG. 4B is a perspective view of the pan shaft 12 viewed from the rear side.

  The pan shaft 12 is formed with a hole 12a for passing a lead wire for electrically connecting the pan coils 171 and 181 and the LED 122, and a step portion 12b for fitting the mirror 123 therein. In addition, the inside of the pan shaft 12 is hollow in order to pass a lead wire that electrically connects the pan coils 171 and 181 and the LED 122. In addition, at both ends of the pan shaft 12, a fitting portion 12c that is cut out in a planar shape is formed at four peripheral surfaces, and an end portion 12d continues to the fitting portion 12c. As will be described later, the pan shaft 12 is used as a rotating shaft that rotates the mirror 123 in the Pan direction.

  An LED 122 is mounted on the back side of the pan shaft 12. The LED 122 is a diffusion type (wide directional type) and can diffuse light over a wide range. As will be described later, the diffused light from the LED 122 is used to detect the scanning position in the target region of the scanning laser light. The LED 122 is attached to the LED substrate 121. The LED substrate 121 is attached to the pan shaft 12 from the rear direction.

  FIG. 5 is a diagram showing the configuration of the pan magnet unit 13. 5A is a diagram illustrating the configuration of the pan magnet 131, FIG. 5B is a diagram illustrating the configuration of the pan magnet holder 132, and FIG. 5C is a diagram illustrating the configuration of the pan magnet 131 and the pan magnet holder 132. It is a figure which shows the assembled state.

  The pan magnet unit 13 includes a pan magnet 131 and a pan magnet holder 132. The pan magnet 131 has a substantially circular shape and is equally divided into four regions in the circumferential direction. Further, the polarity and arrangement of the pan magnet 131 are adjusted so that a rotational force about the pan shaft 12 is generated by applying a current to the pan coil 171 (see FIG. 2) in a state where the mirror actuator 1 is assembled. ing. In the pan magnet 131, adjacent regions have different polarities.

  The pan magnet holder 132 is made of a magnetic material and enhances the action of a magnetic field generated in the pan magnet 131. The pan magnet holder 132 is attracted and fixed to the pan magnet 131. After the arrangement adjustment of the pan magnet 131 with respect to the pan magnet holder 132 is completed, an adhesive is introduced through four holes 132 c formed in the pan magnet holder 132, and the pan magnet 131 is bonded and fixed to the pan magnet holder 132. . In addition, the pan magnet holder 132 is formed with screw holes 132 a and 132 b for fixing to the inner unit frame 11.

  The pan magnet unit 14 is configured in the same manner as the pan magnet unit 13 and includes a pan magnet 141 and a pan magnet holder 142 (see FIG. 2). Screw holes 142 a and 142 b are also formed in the pan magnet holder 142.

  The tilt magnet unit 15 has the same configuration as the pan magnet unit 13 (see FIG. 2). The tilt magnet unit 15 includes a tilt magnet 151 and a tilt magnet holder 152. The tilt magnet 151 has a substantially circular shape and is equally divided into four regions. Further, the tilt magnet 151 applies a current to the tilt coil 221 (see FIG. 10B) in a state where the mirror actuator 1 is assembled, so that the rotational force about the tilt shaft 25 (see FIG. 1) is applied. Polarity and placement are adjusted to occur. In the tilt magnet 151, adjacent regions have different polarities.

  The tilt magnet holder 152 is made of a magnetic material and enhances the action of a magnetic field generated in the tilt magnet 151. The tilt magnet holder 152 is attracted and fixed to the tilt magnet 151. After the adjustment of the arrangement of the tilt magnet 151 with respect to the tilt magnet holder 152 is completed, an adhesive material flows in through the four holes formed in the tilt magnet holder 152, and the tilt magnet 151 is bonded and fixed to the tilt magnet holder 152. The tilt magnet holder 152 is formed with screw holes 152 a and 152 b for fixing to the inner unit frame 11.

  The tilt magnet unit 16 is configured in the same manner as the tilt magnet unit 15 and includes a tilt magnet 161 and a tilt magnet holder 162. The tilt magnet holder 162 is also formed with screw holes 162a and 162b.

  FIG. 6 is a diagram showing a configuration of the pan coil unit 17. 6A is an exploded perspective view when the pan coil unit 17 is viewed from the lower side, FIG. 6B is a perspective view when the pan coil holder 172 is viewed from the upper side, and FIG. It is a perspective view when the pan coil unit 17 is seen from the upper side. Since the configuration of the pan coil unit 18 is substantially the same as that of the pan coil unit 17, the numbers of the respective parts of the pan coil unit 17 and the numbers of the respective parts of the pan coil unit 18 corresponding thereto are given in FIG. ing. Here, for convenience, the pan coil unit 17 will be described.

  With reference to FIG. 6A, the pan coil unit 17 includes a pan coil 171, a pan coil holder 172, a yoke 173, and a suspension wire fixing substrate 174.

  The pan coil holder 172 is made of a resin material. The pan coil holder 172 is provided with four pan coil mounting portions 172a. The pan coil mounting part 172a has a structure in which a wall is formed around a substantially fan-shaped opening that penetrates vertically. Each of the four pan coil mounting portions 172a is fixed so that the pan coil 171 is wound along the wall. The four pan coils 171 have the same substantially fan shape. When the four pan coils 171 are respectively mounted on the corresponding pan coil mounting portions 172a, the outline of the entire pan coil 171 becomes a substantially circular shape in plan view. In this state, the four pan coils 171 are evenly arranged in the circumferential direction so that the fan-shaped sides are adjacent to each other. The four pan coils 171 are connected in series, and the winding direction is adjusted so that an electromagnetic driving force in the same rotational direction is generated in each pan coil 171 by flowing current in a state where the mirror actuator 1 is assembled. Has been.

  In addition, a shaft hole 172 b for passing the end of the pan shaft 12 is provided in the center of the pan coil holder 172. The shaft hole 172b has a contour with a rounded apex angle in a plan view so as to be fitted to the fitting portion 12c of the pan shaft 12. Further, a shaft hole 173 a for allowing the end 12 d of the pan shaft 12 to pass is provided in the center of the yoke 173. The yoke 173 enhances the action of the magnetic field of the opposing pan magnet 131.

  Further, the corner of the pan coil holder 172 is raised in a trapezoidal shape, and two wire holes 172c for passing the suspension wires 19a and 19b and two wire holes 172d for passing the suspension wires 19c and 19d are passed through this portion. Is formed. The wire holes 172c and 172d penetrate vertically. The suspension wire fixing substrate 174 has a rectangular thin plate shape.

  The suspension wire fixing substrate 174 is made of glass epoxy resin. The suspension wire fixing substrate 174 has two terminal holes 174b for passing the suspension wires 19a and 19b and two terminal holes 174c for passing the suspension wires 19c and 19d at positions corresponding to the wire holes 172c and 172d. Is formed. The terminal holes 174b and 174c penetrate vertically. Further, as shown in FIG. 6C, recesses for placing solder are formed around the terminal holes 174b and 174c on the upper surface of the suspension wire fixing substrate 174.

  Moreover, as shown in FIG.6 (b), cylindrical convex part 172e, 172f is formed in the upper surface of the pan coil holder 172. As shown in FIG. Two holes 173b are formed in the yoke 173 at positions corresponding to the convex portions 172e. The yoke 173 is positioned in the pan coil holder 172 by passing the hole 173b through the convex portion 172e. In this state, the yoke 173 is bonded and fixed to the upper surface of the pan coil holder 172.

  In the suspension wire fixing substrate 174, two holes 174a are formed at positions corresponding to the convex portions 172f. The suspension wire fixing substrate 174 is positioned with respect to the pan coil holder 172 by passing the hole 174a through the convex portion 172f. In this state, the suspension wire fixing substrate 174 is bonded and fixed to the upper surface of the pan coil holder 172. Thereby, the pan coil unit 17 shown in FIG. 6C is completed.

  In this state, the position of the shaft hole 172 b of the pan coil holder 172 is matched with the position of the shaft hole 173 a of the yoke 173. Further, the position of the wire hole 172c of the pan coil holder 172 is aligned with the position of the terminal hole 174b of the suspension wire fixing substrate 174, and the position of the wire hole 172d of the pan coil holder 172 is the position of the terminal hole 174c of the suspension wire fixing substrate 174. To fit the position.

  The pan coil unit 18 is configured in substantially the same manner as the pan coil unit 17. However, since the suspension wires 19a to 19d are not passed through the suspension wire fixing substrate 184 of the pan coil unit 18, no wire holes are provided in the pan coil holder 182, and the suspension wire fixing substrate 184 has terminals. There is no hole.

  Returning to FIG. 2, the suspension wires 19 a to 19 d are made of phosphor bronze, beryllium copper, or the like, have excellent conductivity, and have spring properties. The suspension wires 19a to 19d have a circular cross section. The suspension wires 19a to 19d have the same shape and characteristics as each other, and are used to supply a stable load when supplying current to the pan coils 171 and 181 and the LED 122 and rotating the mirror 123 in the Pan direction. Note that the suspension wires 19a to 19d do not substantially expand and contract even when a force is applied in the longitudinal direction.

  FIG. 7 is a diagram illustrating the configuration of the suspension wire fixing substrates 191 and 192. FIGS. 7A and 7B are perspective views of the suspension wire fixing substrate 191 as viewed from above and below, respectively. 7C and 7D are perspective views of the suspension wire fixing substrate 192 when viewed from the upper side and the lower side, respectively.

  Referring to FIG. 7A, the suspension wire fixing substrate 191 is a circuit substrate made of glass epoxy resin or the like and has flexibility. The suspension wire fixing substrate 191 is formed with two terminal holes 191a for passing the suspension wires 19a, 19b and two terminal holes 191b for passing the suspension wires 27a, 27b. The suspension wire fixing substrate 191 is formed with a circuit pattern 191c for electrically connecting the terminal hole 191a and the terminal hole 191b.

  The suspension wire fixing substrate 191 has a hole 191d. The suspension wire fixing substrate 191 is bonded and fixed to the bottom surface of the inner unit frame 11 through a hole 191d through a projection 11r (see FIG. 3B) formed on the bottom surface of the inner unit frame 11.

  The suspension wire fixing substrate 192 is configured to be bilaterally symmetrical with the suspension wire fixing substrate 191. 7C and 7D, the suspension wire fixing substrate 192 has two terminal holes 192a, two terminal holes 192b, a circuit pattern 192c, and a hole 192d. The suspension wire fixing substrate 192 is bonded and fixed to the bottom surface of the inner unit frame 11 through a hole 192d through a protrusion 11t (see FIG. 3B) formed on the bottom surface of the inner unit frame 11.

  Referring to FIG. 2, when assembling inner unit 10, first, pan shaft 12 is passed through shaft hole 11 n and accommodated in inner unit frame 11. And the mirror 123 is engage | inserted by the step part 12b of the pan shaft 12, and the bearing 11p is attached to the axis | shaft of the both ends of the pan shaft 12. As shown in FIG. In this state, the two bearings 11p are fitted into the shaft holes 11n formed in the inner unit frame 11. Further, two bearings 11 o for the tilt shafts 25 and 26 are fitted into shaft holes 11 m formed in the inner unit frame 11. Thereby, the assembly shown in FIG. 8A is completed. In FIGS. 8A to 8D, the mirror 123 is omitted for convenience. In the state of FIG. 8A, the suspension wire fixing substrates 191 and 192 are mounted on the lower surface of the inner unit frame 11 as described above.

  Thereafter, as shown in FIG. 8B, the pan magnet holder 132 is fitted into the magnet mounting groove 11a of the inner unit frame 11, and the screw holes 132a and 132b and the screw holes 11b and 11c are combined. In this state, the screws 13a and 13b are screwed into the screw holes 11b and 11c through the screw holes 132a and 132b. Thereby, the pan magnet unit 13 is fixed to the inner unit frame 11. Similarly, the pan magnet unit 14 is fixed to the inner unit frame 11 with screws 14a and 14b.

  8C, the tilt magnet holder 162 is fitted into the magnet mounting groove 11j of the inner unit frame 11, and the screw holes 162a and 162b and the screw holes 11k and 11l are combined. In this state, the screws 16a and 16b are screwed into the screw holes 11k and 11l through the screw holes 162a and 162b. Thereby, the tilt magnet unit 16 is fixed to the inner unit frame 11. Similarly, the tilt magnet unit 15 is fixed to the inner unit frame 11 with screws 15a and 15b.

  Next, the pan coil units 17 and 18 are passed through the fitting portions 12 c at both ends of the pan shaft 12, and the pan coil units 17 and 18 are respectively attached to both ends of the pan shaft 12. Thereby, the assembly of FIG. 8D is completed. Then, nuts 124 and 125 are respectively attached to the end portions 12d at both ends of the pan shaft 12, and the pan coil units 17 and 18 are respectively fixed to both ends of the pan shaft 12. As a result, the pan coil units 17 and 18 can rotate integrally with the pan shaft 12.

  In this state, the terminal hole 174b of the suspension wire fixing substrate 174 faces the terminal hole 191a of the suspension wire fixing substrate 191 and the terminal hole 174c of the suspension wire fixing substrate 174 faces the terminal hole 192a of the suspension wire fixing substrate 192. To do. Then, the suspension wires 19a and 19b are passed through the terminal holes 191a of the suspension wire fixing substrate 191 through the terminal holes 174b of the suspension wire fixing substrate 174 and the wire holes 172c of the pan coil holder 172. Similarly, it is passed through the terminal hole 192a of the suspension wire fixing substrate 192 through the terminal hole 174c of the suspension wire fixing substrate 174 and the wire hole 172d of the pan coil holder 172. The suspension wires 19a to 19d are soldered to the suspension wire fixing substrates 174, 191 and 192 together with the pan coils 171 and 181 and the lead wires for supplying current to the LEDs 122, respectively.

  Thereby, as shown in FIG. 9, the assembly of the inner unit 10 is completed. FIG. 9A is a perspective view of the assembled inner unit 10 viewed from the front side, and FIG. 9B is a perspective view of the assembled inner unit 10 viewed from the rear side. In this state, the mirror 123 can rotate around the pan shaft 12 in the Pan direction. The pan coil units 17 and 18 rotate in the Pan direction as the mirror 123 rotates in the Pan direction. On the other hand, since the suspension wire fixing substrates 191 and 192 are fixed to the lower surface of the inner unit 10, they do not rotate in the Pan direction as the mirror 123 rotates in the Pan direction.

  Returning to FIG. 1, the outer unit 20 includes an actuator frame 21, tilt coil units 22, 23, a servo unit 24, tilt shafts 25, 26, and suspension wires 27a to 27d.

  Referring to FIG. 10, the actuator frame 21 is composed of a frame member whose front is opened. In the center of the left and right side surfaces of the actuator frame 21, shaft holes 21a and 21d for allowing the tilt shafts 25 and 26 to pass are formed. Screw holes 21b, 21c, 21e, and 21f for fixing the tilt coil units 22 and 23 are formed on the left and right side surfaces of the actuator frame 21. In addition, an opening 21g for passing the pinhole box 244 of the servo unit 24 and screw holes 21h and 21i for fixing the servo unit 24 are formed on the rear side surface of the actuator frame 21.

  FIG. 10B is a diagram illustrating the configuration of the tilt coil unit 22. Since the configuration of the tilt coil unit 23 is the same as that of the tilt coil unit 22, the numbers of the respective parts of the tilt coil unit 22 and the numbers of the respective parts of the tilt coil unit 23 corresponding thereto are given in FIG. Yes. Here, for convenience, the tilt coil unit 23 will be described.

  With reference to FIG. 10B, the tilt coil unit 22 includes a tilt coil 221 and a tilt coil holder 222.

  The tilt coil holder 222 is made of a resin material. The tilt coil holder 222 is provided with four tilt coil mounting portions 222a. The tilt coil mounting portion 222a has a configuration in which a wall is formed around a substantially fan-shaped opening penetrating vertically. A tilt coil 221 is fixed to each of the four tilt coil mounting portions 222a so as to be wound along the wall. The four tilt coils 221 have substantially the same fan shape. When the four tilt coils 221 are respectively mounted on the corresponding tilt coil mounting portions 222a, the entire outline of the tilt coil 221 becomes a substantially circular shape in plan view. In this state, the four tilt coils 221 are evenly arranged in the circumferential direction so that the fan-shaped sides are adjacent to each other. The four tilt coils 221 are connected in series, and an electric current flows in the assembled state of the mirror actuator 1, so that an electromagnetic driving force in the same rotational direction is generated between each tilt coil 221 and the tilt magnet unit 15. The winding direction is adjusted so as to generate.

  In the center of the tilt coil holder 222, a circular shaft hole 222b through which the tilt shaft 25 is passed is provided. Further, screw holes 222 c and 222 d for fixing to the actuator frame 21 are formed at both ends of the tilt coil holder 222.

  The tilt coil unit 23 is configured in the same manner as the tilt coil unit 22. Here, detailed description of each part is omitted.

  Referring to FIG. 10C, the servo unit 24 includes a PSD substrate 241, a PSD 242, a band pass filter 243, and a pinhole box 244.

  Two screw holes 241 a and 241 b for fixing the PSD substrate 241 to the actuator frame 21 are formed in the PSD substrate 241. On the back surface of the PSD substrate 241, two terminal holes 241c (not shown in FIG. 10C, see FIG. 13B) for passing the suspension wires 27a and 27b are formed. In addition, two terminal holes 241d (not shown in FIG. 10C, see FIG. 13B) through which the suspension wires 27c and 27d are passed are formed on the back surface of the PSD substrate 241. A PSD 242 is mounted on the PSD substrate 241. The PSD 242 outputs a signal corresponding to the light receiving position of the servo light.

  The bandpass filter 243 transmits only light in the wavelength band emitted from the LED 122 and removes stray light in other wavelength bands. The band pass filter 243 is attached to the surface of the PSD 242 and is bonded and fixed.

  As shown in FIG. 10D, the pinhole box 244 has a hollow inside, and a pinhole 244a is formed at the center. The pinhole 244a transmits a part of the diffused light emitted from the LED 122. The pinhole box 244 is made of a light shielding material and prevents stray light other than light transmitted through the pinhole 244a from entering the PSD 242. The pinhole box 244 is attached to the PSD substrate 241 and bonded and fixed.

  Returning to FIG. 10A, when assembling the outer unit 20, first, the tilt coil units 22 and 23 are attached to the left and right side surfaces of the actuator frame 21. In this state, the screws 22a and 22b are screwed into the screw holes 21b and 21c through the screw holes 222c and 222d. Thereby, the tilt coil unit 22 is fixed to the actuator frame 21. Similarly, the screws 23a and 23b are screwed into the screw holes 21e and 21f through the screw holes 232c and 232d. Thereby, the tilt coil unit 23 is fixed to the actuator frame 21.

  Next, the PSD substrate 241 is attached to the back surface of the actuator frame 21. In this state, the screws 24a and 24b are screwed into the screw holes 21h and 21i through the screw holes 241a and 241b. Thereby, the servo unit 24 is fixed to the actuator frame 21. Thus, the structure shown in FIG. 1 is assembled.

  FIG. 11A is an exploded perspective view showing configurations of the tilt shaft 25, the magnet holder for magnetic spring 251 and the magnet for magnetic spring 252, and FIG. 11B is a perspective view showing a state in which these are combined. It is. The configuration of the tilt shaft 25, the magnetic spring magnet holder 251, and the magnetic spring magnet 252 is the same as the configuration of the tilt shaft 25, the magnetic spring magnet holder 251, and the magnetic spring magnet 252, so that FIG. For convenience, the numbers of the corresponding parts of the tilt shaft 26, the magnet holder for magnetic spring 261, and the magnet for magnetic spring 262 are given.

  The tilt shaft 25 has a step 25 a slightly smaller than the diameter of the shaft hole 21 a of the actuator frame 21, a step 25 b slightly smaller than the diameter of the bearing 11 o of the inner unit frame 11, and the diameter of the magnet holder 251 for the magnetic spring. A slightly smaller step portion 25c is formed.

  The magnetic spring magnet holder 251 is made of a hard material (for example, a resin material) so as not to be deformed even when a force is applied. The magnetic spring magnet holder 251 is formed with a cylindrical body 251a, a flange 251b formed on the bottom surface of the body 251a, and a circular hole 251c penetrating the center of the body 251a. The diameter of the hole 251c is substantially the same as the diameter of the step portion 25c of the tilt shaft 25.

  The magnet for magnetic spring 252 has a disk shape, and a circular hole 252a is formed at the center. The diameter of the hole 252a is slightly larger than the diameter of the body 251a of the magnet holder 251 for magnetic springs. The magnetic spring magnet 252 is equally divided into four regions in the circumferential direction. In the assembled state shown in FIG. 13, each region is opposed to the tilt magnet 151 (see FIG. 2) and attracts each other. The polarity is adjusted. In the assembled state shown in FIG. 13, the area division position of the magnetic spring magnet 252 is arranged to correspond to the area division position of the tilt magnet 151 (see FIG. 5A).

  The magnetic spring magnet 252 is bonded and fixed to the magnetic spring magnet holder 251 with the hole 252a fitted into the body 251a and the bottom surface placed on the flange 251b. Further, the hole 251c of the magnet holder 251 for magnetic spring is press-fitted into the step portion 25c of the tilt shaft 25, and the tip of the step portion 25c is bonded to the upper surface of the trunk portion 251a. FIG. 11B shows a state in which the magnetic spring magnet 252, the magnetic spring magnet holder 251, and the tilt shaft 25 are integrated. However, during actual assembly, the actuator frame 21 of the outer unit 20 and the tilt coil unit 22 are interposed between the magnet holder 251 for the magnetic spring and the tilt shaft 25.

  The tilt shaft 26 is configured in the same manner as the tilt shaft 25. The magnetic spring magnet holder 261 is configured in the same manner as the magnetic spring magnet holder 251. The magnetic spring magnet 262 is configured in the same manner as the magnetic spring magnet 252. The tilt shaft 26, the magnetic spring magnet holder 261, and the magnetic spring magnet 262 are also integrated in the same manner as described above.

  Returning to FIG. 1, the suspension wires 27a to 27d are made of phosphor bronze, beryllium copper, or the like, have excellent conductivity, and have spring properties. The suspension wires 27a to 27d have a rectangular cross section. The suspension wires 27 a to 27 d have the same shape and characteristics as each other, and are used for supplying current to the pan coils 171 and 181 and the LED 122. The suspension wires 27a to 27d have a shape curved backward in a normal state.

  When the inner unit 10 and the outer unit 20 are assembled, the inner unit 10 is first accommodated in the outer unit 20. Then, as shown in FIG. 12, from the left, the step portion 25 a of the tilt shaft 25 is passed through the shaft hole 21 a of the actuator frame 21, and the step portion 25 b is passed through the bearing 11 o of the inner unit frame 11. Thereafter, the magnet holder 251 for the magnetic spring is passed through the step portion 25c of the tilt shaft 25, and is fixed by adhesion.

  Similarly, from the right, the step portion 26 a of the tilt shaft 26 is passed through the shaft hole 21 d of the actuator frame 21, and the step portion 26 b is passed through the bearing 11 o of the inner unit frame 11. Then, the magnet holder 261 for magnetic spring is passed through the step portion 26c of the tilt shaft 26 and is fixedly bonded.

  In this state, the tilt shafts 25 and 26 are rotated, and the positions of the magnetic spring magnets 252 and 262 in the rotational direction are adjusted. Specifically, with the inner unit 10 standing upright in the vertical direction, each magnetic pole region of the magnetic spring magnets 252 and 262 is in a position directly opposite to the corresponding magnetic pole region of the tilt magnets 151 and 161. The positions of the magnets 252 and 262 are adjusted. After such adjustment is completed, the tilt shafts 25 and 26 are bonded and fixed to the actuator frame 21.

  Thereby, even if the inner unit frame 11 rotates in the tilt direction, the tilt shafts 25 and 26 and the magnets for magnetic springs 252 and 262 are fixed so as not to rotate. On the other hand, the tilt magnets 151 and 161 rotate integrally with the inner unit frame 11.

  When the inner unit frame 11 is not rotating, the position of the boundary between the magnetic spring magnets 252 and 262 and the position of the boundary between the tilt magnets 151 and 161 are the same. Further, the polarities of the respective regions of the magnetic spring magnets 252 and 262 are different from the polarities of the respective regions of the opposing tilt magnets 151 and 161. Accordingly, the tilt magnets 151 and 161 are attracted in the right direction and the left direction, respectively, whereby a right direction force and a left direction force act on the inner unit frame 11. In the state of FIG. 12, these two forces are balanced with each other. Therefore, the inner unit frame 11 is supported by the outer frame 21 without being urged in the left or right direction.

  As shown in FIG. 12, in such an attached state, between the bearing 11o and the magnetic spring magnet holder 251, between the bearing 11o and the magnetic spring magnet holder 261, between the tilt magnet 151 and the tilt coil 221, and A gap is generated between the tilt magnet 161 and the tilt coil 231. The clearance between the bearing 11o and the magnetic spring magnet holder 251 and the clearance between the bearing 11o and the magnetic spring magnet holder 261 are the clearance between the tilt magnet 151 and the tilt coil 221 and the tilt magnet 161. It is considerably smaller than the gap between the tilt coil 231 and the coil. For this reason, the inner unit frame 11 is slightly movable in the left-right direction by the gap between the bearing 11o and the magnet holder for magnetic spring 251 and the gap between the bearing 11o and the magnet holder for magnetic spring 261. However, even if the inner unit frame 11 moves to the left and right, the tilt magnets 151 and 161 do not collide with the tilt coils 221 and 231.

  From the state of FIG. 12, when the left bearing 11o contacts the magnetic spring magnet holder 251, the distance between the magnetic spring magnet 252 and the tilt magnet 151 is the same as the magnetic spring magnet 262 and the tilt magnet 161. Less than the distance between. For this reason, the magnetic force applied to the right and left of the inner unit frame 11 is stronger when it acts in the right direction. Due to the unbalance of the magnetic force, the left bearing 11o is kept in contact with the magnetic spring magnet holder 251 until an external force is applied in the left direction thereafter. That is, the inner unit frame 11 is rotated in the tilt direction in a state where the left bearing 11o is in contact with the magnet holder 251 for the magnetic spring.

  Thus, when the inner unit 10 is rotatably attached to the outer unit 20, as shown in FIG. 13B, one end of the suspension wires 27a and 27b is passed through the terminal hole 191b of the suspension wire fixing substrate 191. Soldered. Further, the other ends of the suspension wires 27a and 27b are passed through the two terminal holes 241c of the PSD substrate 241 and soldered.

  Similarly, one end of each of the suspension wires 27c and 27d is passed through the terminal hole 192b of the suspension wire fixing substrate 192 and soldered. The other ends of the suspension wires 27c and 27d are passed through the two terminal holes 241d of the PSD board 241 and soldered. When the mirror surface of the mirror 123 is perpendicular to the horizontal direction as shown in FIG. 13A, the suspension wires 27a to 27d are connected to the terminal holes 191b and 192b without being substantially deformed from the normal state. It has a shape curved backward so as to connect 241c and 241d. Thereby, the suspension wires 27a to 27d can have a length necessary when the inner unit frame 11 rotates in the tilt direction without applying unnecessary force to the inner unit frame 11 as much as possible. Further, current is supplied to the pan coils 171 and 181 and the LED 122 attached to the inner unit frame 11 by the suspension wires 27a to 27d.

  In addition, although not shown, a conductive wire is directly connected to the tilt coils 221 and 231 from the PSD substrate 241 and supplied with current. Since the tilt coils 221 and 231 are attached to the actuator frame 21 that does not rotate, even if the conductive wire is directly connected, the rotation of the mirror 123 is not affected.

  Thus, the assembly of the mirror actuator 1 is completed. FIG. 13A is a perspective view of the mirror actuator 1 viewed from the front, and FIG. 13B is a perspective view of the mirror actuator 1 viewed from the rear. In this state, the inner unit frame 11 can be rotated around the tilt shafts 25 and 26 in the tilt direction. The pan coil units 17 and 18 and the suspension wire fixing substrates 191 and 192 rotate in the tilt direction as the inner unit frame 11 rotates in the tilt direction.

  In the assembled state shown in FIG. 13, when a current is passed through the pan coils 171 and 181, the pan shaft 12 is rotated together with the pan coil units 17 and 18 by the electromagnetic driving force generated in the pan coils 171 and 181 and the pan magnets 131 and 141. As a result, the mirror 123 rotates in the Pan direction about the pan shaft 12.

  When the mirror 123 rotates in the Pan direction, the pan coil units 17 and 18 rotate integrally, and the suspension wire fixing substrates 191 and 192 do not rotate. Therefore, the suspension wires 19a and 19b and the suspension wires 19c and 19d are respectively positioned at the twisted positions around the pan shaft 12 while being pulled in the longitudinal direction. At this time, since the suspension wires 19a to 19d do not expand and contract in the longitudinal direction, the suspension wire fixing substrates 191 and 192 having flexibility are pulled upward. In this way, due to the spring properties of the suspension wires 19a to 19d and the suspension wire fixing substrates 191 and 192, a torque is generated in the direction opposite to the Pan direction of the mirror 123 around the pan shaft 12. This moment is a predetermined value that can be calculated based on the spring constants of the suspension wires 19a to 19d and the suspension wire fixing substrates 191 and 192 and the rotational position of the mirror 123 around the pan shaft 12. Thus, when the mirror 123 is rotated in the Pan direction, a reverse torque is always generated. Therefore, when the current application to the pan coils 171 and 181 is stopped, the mirror 123 returns to the position before the rotation. It is.

  Thus, the force required to rotate the mirror 123 in the Pan direction depends on the spring properties of the suspension wires 19a to 19d and the suspension wire fixing substrates 191 and 192. Therefore, the resonance frequency necessary for the rotation of the mirror 123 can be adjusted by adjusting the spring property. The suspension wires 19a to 19d are stretched in a straight line, and the suspension wires 19a to 19d are replaced with different spring constants, or the suspension wires 19a to 19d are replaced with different diameters. Easy. As described above, the resonance frequency of the mirror 123 in the Pan direction can be adjusted only by a simple operation of exchanging the suspension wires 19a to 19d or the suspension wire fixing substrates 191 and 192.

  In the assembled state shown in FIG. 13, when an electric current is passed through the tilt coils 221 and 231, the inner unit frame 11 is tilted together with the pan coil units 17 and 18 by the electromagnetic driving force generated in the tilt coils 221 and 231 and the tilt magnets 151 and 161. The mirror 123 rotates in the tilt direction about the shafts 25 and 26, thereby rotating the mirror 123 in the tilt direction.

  FIG. 14 is a diagram illustrating the operation of the magnet 252 for magnetic spring. The magnetic spring magnet 262 also has the same operation as described below, but only the operation of the magnetic spring magnet 252 will be described here.

  FIG. 14A is a diagram showing a positional relationship between the tilt magnet 151 and the magnetic spring magnet 252 when the inner unit frame 11 is not rotated in the tilt direction. In this state, the mirror surface of the mirror 123 is perpendicular to the horizontal plane. The position of the inner unit frame 11 at this time is referred to as a “tilt neutral position”.

  FIG. 14B is a diagram schematically showing the positional relationship between the tilt magnet 151 and the magnetic spring magnet 252 when the inner unit frame 11 is in the tilt neutral position. In FIG. 14B, for the sake of convenience, the tilt magnet 151 and the magnetic spring magnet 252 are shown to be different in size, but actually, the tilt magnet 151 and the magnetic spring magnet 252 are substantially the same. It has the same size. In FIG. 14B, the tilt coil 221 is indicated by a broken line.

  As shown in FIG. 14B, when the inner unit frame 11 is in the tilt neutral position, the position of the area division of the tilt magnet 151 and the position of the area division of the magnet for magnetic spring 252 coincide. Therefore, the tilt magnet 151 and the magnetic spring magnet 252 are positioned so that the N pole and the S pole face each other. Therefore, a pulling force is generated between the tilt magnet 151 and the magnetic spring magnet 252 only in a direction approaching each other.

  In the state of FIG. 14B, when a current flows through the tilt coil 221, a tilt direction is applied to the tilt magnet 151 by an electromagnetic driving force generated by applying a magnetic field from the tilt magnet 151 to the linear portion 221 a of the tilt coil 221. The driving force is applied. With this driving force, the tilt magnet 151 rotates in the tilt direction.

  As shown in FIG. 14C, when the inner unit frame 11 rotates in the tilt direction from the tilt neutral position, the tilt magnet 151 rotates with the inner unit frame 11, but the magnetic spring magnet 252 Since it is fixed to the tilt shaft 25, it does not rotate. For this reason, as shown in FIG. 14D, the position of the area division of the tilt magnet 151 and the position of the area division of the magnetic spring magnet 252 are shifted in the circumferential direction. Accordingly, a part of the N pole region of the tilt magnet 151 faces a part of the N pole region of the magnetic spring magnet 252, and a part of the S pole region of the tilt magnet 151 is set to the magnetic spring magnet 252. It faces a part of the S pole region. For this reason, a magnetic force that pulls the tilt magnet 151 back to the tilt neutral position is generated in each region of the tilt magnet 151. Thereby, torque (drag) toward the tilt neutral position is applied to the inner unit frame 11. This torque (drag) is a predetermined value that can be calculated by the strength of the magnetic force generated between the tilt magnet 151 and the magnetic spring magnet 252 and the rotational position of the inner unit frame 11. Thus, when the mirror 123 is rotated integrally with the inner unit frame 11 from the tilt neutral position, a reverse torque is always generated. Therefore, when the application of current to the tilt coils 221 and 231 is stopped, the mirror 123 is stopped. Is returned to the tilt neutral position.

  Thus, the force required to rotate the mirror 123 in the tilt direction depends on the magnitude of the magnetic force generated between the tilt magnets 151 and 161 and the magnetic spring magnets 252 and 262. Therefore, the resonance frequency of the mirror 123 in the tilt direction can be adjusted by adjusting the magnetic force.

  The magnitude of the magnetic force generated between the tilt magnets 151 and 161 and the magnetic spring magnets 252 and 262 can be adjusted by adjusting the size, shape, and magnetic strength of the magnetic spring magnets 252 and 262, for example. it can. In addition, by changing the distance between the tilt magnets 151 and 161 and the magnetic spring magnets 252 and 262, the magnitude of the magnetic force generated between the tilt magnets 151 and 161 and the magnetic spring magnets 252 and 262 can be changed. It can also be changed.

  FIG. 15 is a diagram illustrating a configuration example when adjusting the magnetic force generated between the tilt magnets 151 and 161 and the magnets 252 and 262 for the magnetic spring. Here, a configuration example on the magnetic spring magnet 252 side will be described. The configuration example on the magnetic spring magnet 262 side is the same as the following.

  In FIG. 15A, the magnetic spring magnet 252 is replaced with one having a thickness D. In this case, the magnetic force generated between the tilt magnet 151 and the magnetic spring magnet 252 is increased. On the other hand, when the magnetic spring magnet 252 is replaced with a thin one, the magnetic force generated between the tilt magnet 151 and the magnetic spring magnet 252 can be reduced. As described above, the drag applied to the inner unit frame 11 can be adjusted only by a simple operation of changing the thickness D of the magnet 252 for the magnetic spring, and the resonance frequency of the mirror 123 in the tilt direction can be adjusted. it can.

  The resonance frequency of the mirror 123 in the tilt direction is not limited to the thickness, but can be changed by changing the diameter or size of the magnet 252 for the magnetic spring, or by replacing it with one having a different magnetic strength without changing the shape. Can be adjusted.

  FIG. 15B is a diagram illustrating a configuration example when the distance between the tilt magnet 151 and the magnetic spring magnet 252 is changed. In this configuration example, a screw groove 25d is provided in the step portion 25c of the tilt shaft 25, and a screw groove 251d that meshes with the screw groove 25d is provided in the hole 251c of the magnet holder for magnetic spring 251.

  In this case, as shown in FIG. 15C, by rotating the magnetic spring magnet holder 251, the position of the magnetic spring magnet 252 can be changed in the axial direction of the tilt shaft 25. The distance L between the magnet 151 and the magnet for magnetic spring 252 can be changed. By increasing the distance L, the magnetic force generated between the tilt magnet 151 and the magnetic spring magnet 252 can be reduced, and by decreasing the distance L, the magnetic force generated between the tilt magnet 151 and the magnetic spring magnet 252 is generated. Magnetic force can be increased.

  As described above, in the configuration examples of FIGS. 15B and 15C, the drag applied to the inner unit frame 11 can be achieved only by a simple operation of changing the distance L between the tilt magnet 151 and the magnetic spring magnet 252. The resonance frequency of the mirror 123 in the tilt direction can be adjusted.

  In the state of FIG. 13, when the tilt shafts 25 and 26 are rotated in the same direction, the magnetic spring magnets 252 and 262 are rotated accordingly, so that the magnetic spring magnets 252 and 262 and the tilt magnet 151 are rotated. The inner unit frame 11 rotates in the tilt direction by the magnetic force between the mirror 162 and the position of the mirror 123 changes. Therefore, the position of the mirror 123 in the tilt direction can be adjusted by rotating the tilt shafts 25 and 26 while no current is flowing into the tilt coils 221 and 231. Grooves for fitting jigs such as drivers are formed in the heads of the tilt shafts 25 and 26. The tilt shafts 25 and 26 are bonded and fixed to the actuator frame 21 after the rotation position is adjusted so that the mirror 123 is in the tilt neutral position.

  FIG. 16 is a diagram illustrating a configuration of the laser radar 300 in a state where the mirror actuator 1 according to the embodiment is mounted.

  16A is a perspective view of the inside of the laser radar 300 seen from the side, and FIG. 16B is an external perspective view of the laser radar 300. FIG.

  Referring to FIG. 16A, the laser radar 300 includes a housing 301, a projection / light receiving window 302, a projection unit 400, a light receiving unit 500, and a circuit board 600.

  The casing 301 has a cubic shape, and houses the projection unit 400, the light receiving unit 500, and the circuit board 600 therein. A projection / light receiving window 302 is attached to the front surface of the housing 301.

  As shown in FIG. 13B, the projection / light receiving window 302 is formed of a curved transparent plate having a curved surface. The projection / light receiving window 302 is made of a highly transparent material, and an antireflection film (AR coating) is attached to the incident surface and the output surface.

  The projection unit 400 includes a laser holder 401, a laser light source 402, a beam shaping lens 403, and the mirror actuator 1.

  The laser holder 401 has a cylindrical shape that is slightly larger in diameter than the laser light source 402 and the beam shaping lens 403, holds the laser light source 402 inside, and the beam shaping lens 403 is attached to the front.

  The laser light source 402 emits laser light having a wavelength of about 900 nm. Since the laser light source 402 increases the scanning range of the laser beam in the target area by the rotation of the mirror 123 in the Pan direction, the emission direction of the laser beam is from the vertical direction (Y axis positive direction) to the in-plane direction of the YZ plane. It arrange | positions so that it may incline to the mirror 123 side. The laser light source 402 is electrically connected to the circuit board 402a.

  The beam shaping lens 403 is attached to the laser holder 401 so that the optical axis of the beam shaping lens 403 matches the outgoing optical axis of the laser light source 402. Further, the beam shaping lens 403 converges the emitted laser light so that the emitted laser light has a predetermined shape in the target region. For example, the beam shape is set so that the beam shape in the target region (in this embodiment, set at a position several tens of meters forward from the projection / light receiving window 302) is an elliptical shape having a length of about 2 m and a width of about 0.2 m. A shaping lens 403 is designed.

  The mirror actuator 1 is installed such that when the mirror 123 is in the neutral position, the incident angle of the laser light emitted from the mirror surface of the mirror 123 of the mirror actuator 1 and the laser light source 402 is a predetermined angle (for example, 60 degrees). Is done. The “neutral position” means a position where the mirror 123 is not rotated by the mirror actuator 1 and is perpendicular to the front-rear direction in FIG. At the neutral position, the laser light from the beam shaping lens 403 enters the approximate center of the mirror 123.

  The light receiving unit 500 includes a lens barrel 501, a band pass filter 502, a light receiving lens 503, and a photodetector 504.

  The lens barrel 501 is equipped with a band pass filter 502, a light receiving lens 503, and a photodetector 504.

  The band pass filter 502 is composed of a dielectric multilayer film, and transmits only light in the wavelength band of the emitted laser light. Note that the band-pass filter 502 has a simple film configuration because the reflected light is incident in a substantially parallel light state.

  The light receiving lens 503 is a Fresnel lens and condenses light reflected from the target area. The Fresnel lens is a lens in which a convex lens is divided into concentric regions to reduce the thickness.

  The photodetector 504 is composed of an APD (avalanche photodiode) or a PIN photodiode, and is mounted on the circuit board 504a. The photodetector 504 outputs an electrical signal having a magnitude corresponding to the amount of received light to the circuit board 504a. The light receiving surface of the photodetector 504 is not divided into a plurality of regions, but is formed of a single light receiving surface. In addition, the light receiving surface of the photodetector 504 has a narrow vertical and horizontal width (for example, around 1 mm) in order to suppress the influence of stray light.

  The laser light emitted from the laser light source 402 is converged by the beam shaping lens 403 and shaped into a predetermined shape in the target area. The laser light transmitted through the beam shaping lens 403 enters the mirror 123 of the mirror actuator 1 and is reflected by the mirror 123 toward the target area.

  As shown in FIG. 16B, the mirror 123 is driven in the Pan direction and the Tilt direction by the mirror actuator 1, whereby the emitted laser light is scanned in the target area. The laser light is scanned along a plurality of scanning lines parallel to the XZ plane in the target area. In order to scan the laser beam along each scanning line, the mirror 123 is driven not only in the Pan direction but also in the Tilt direction. Further, in order to change the scanning line, the mirror 123 is driven in the tilt direction.

  Returning to FIG. 16A, the reflected light from the target area travels back along the optical path of the emitted laser light toward the target area and enters the mirror 123. The reflected light that has entered the mirror 123 is reflected by the mirror 123 and enters the light receiving lens 503 through a gap between the laser holder 401 and the lens barrel 501.

  The behavior of the reflected light is the same regardless of the rotation position of the mirror 123. That is, regardless of the rotational position of the mirror 123, the reflected light from the target area travels back in the optical path of the emitted laser light and travels parallel to the optical axis of the beam shaping lens 403, and reaches the light receiving lens 503. Incident.

  The circuit board 600 is electrically connected to the circuit board 402 a for the laser light source 402, the circuit board 504 a for the photodetector 504, and the PSD board 241 of the mirror actuator 1. The circuit board 600 includes a CPU, a memory, and the like, and controls the laser light source 402 and the mirror actuator 1. Further, the circuit board 600 measures the presence / absence of an object in the target region and the distance to the object based on a signal from the photodetector 504. Specifically, the distance to this object is measured from the time difference between the timing when the laser beam is emitted and the timing when the signal is output from the photodetector 504. The circuit configuration of the laser radar 300 will be described later with reference to FIG.

  FIGS. 17A and 17B are diagrams illustrating a servo optical system for detecting the position of the mirror 123. FIG. 17A shows only a partial sectional view of the mirror actuator 1 and the laser light source 402.

  Referring to FIG. 17A, as described above, the mirror actuator 1 is provided with the LED 122, the pinhole box 244, the PSD substrate 241, and the PSD 242.

  The LED 122, PSD 242 and pin hole 244a are arranged so that the LED 122 faces the pin hole 244a of the pin hole box 244 and the center of the PSD 242 when the mirror 123 of the mirror actuator 1 is in the neutral position. That is, the pinhole box 244 and the PSD 242 are arranged so that the servo light emitted from the LED 122 and passing through the pinhole 244a is perpendicularly incident on the center of the PSD 242 when the mirror 123 is in the neutral position. Further, the pinhole box 244 is disposed at a position closer to the PSD 242 than an intermediate position between the LED 122 and the PSD 242.

  Here, a part of the servo light emitted so as to diffuse from the LED 122 passes through the pinhole 244 a and is received by the PSD 242. The servo light incident on the area other than the pinhole 244a is shielded by the pinhole box 244. The PSD 242 outputs a current signal corresponding to the light receiving position of the servo light.

  For example, as shown in FIG. 17B, when the mirror 123 rotates from the neutral position indicated by the broken line in the direction of the arrow, the optical path of the light passing through the pinhole 244a out of the diffused light (servo light) of the LED 122 is from LP1 to LP2. And displace. As a result, the irradiation position of the servo light on the PSD 242 changes, and the position detection signal output from the PSD 242 changes. In this case, the light emission position of the servo light from the LED 122 and the incident position of the servo light on the light receiving surface of the PSD 242 have a one-to-one correspondence. Therefore, the position of the mirror 123 can be detected based on the incident position of the servo light detected by the PSD 242, and as a result, the scanning position of the scanning laser light in the target area can be detected.

  FIG. 18 is a diagram illustrating a circuit configuration of the laser radar 300. For the sake of convenience, the main configuration of the laser radar 300 is also shown in FIG. As shown in the figure, the laser radar 300 includes a PSD signal processing circuit 601, a servo LED driving circuit 602, an actuator driving circuit 603, a scan LD driving circuit 604, a PD signal processing circuit 605, and a DSP 606.

  The PSD signal processing circuit 601 outputs a position detection signal obtained based on the output signal from the PSD 242 to the DSP 606. The servo LED drive circuit 602 supplies a drive signal to the LED 122 based on the signal from the DSP 606. The actuator drive circuit 603 drives the mirror actuator 1 based on the signal from the DSP 606. Specifically, a drive signal for scanning the laser beam along a predetermined trajectory in the target area is supplied to the mirror actuator 1.

  The scan LD drive circuit 604 supplies a drive signal to the laser light source 402 based on the signal from the DSP 606. Specifically, a pulsed drive signal (current signal) is supplied to the laser light source 402 at the timing of irradiating the target region with laser light.

  The PD signal processing circuit 605 amplifies and digitizes a voltage signal corresponding to the amount of light received by the photodetector 504 and supplies the amplified signal to the DSP 606.

  The DSP 606 detects the scanning position of the laser beam in the target area based on the position detection signal input from the PSD signal processing circuit 601, and executes drive control of the mirror actuator 1, drive control of the laser light source 402, and the like. . The DSP 606 determines whether an object is present at the laser light irradiation position in the target area based on the voltage signal input from the PD signal processing circuit 605, and at the same time, the laser light output from the laser light source 402 The distance to the object is measured based on the time difference between the irradiation timing and the light reception timing of the reflected light from the target area received by the photodetector 504.

  As described above, according to the present embodiment, since the magnetic spring magnets 252 and 262 are provided, a simple operation of changing the thickness of the magnetic spring magnets 252 and 262, the strength of the magnetic force, and the like can be performed. The resonance frequency of the mirror 123 can be adjusted.

  In addition, according to the present embodiment, since the magnetic spring magnets 252 and 262 are mounted on the tilt shafts 25 and 26 of the rotation shaft in the tilt direction, the members for mounting the magnetic spring magnets 252 and 262 are mounted. Therefore, the mirror actuator 1 can be configured compactly.

  Further, according to the present embodiment, since the magnetic spring magnets 252 and 262 are mounted on the magnetic spring magnet holders 251 and 261, the magnetic spring magnets 252 and 262 can be easily replaced.

  Further, as shown in FIG. 15B, if the tilt shafts 25 and 26 are formed in a screw shape, the positions of the magnetic spring magnets 252 and 262 can be easily changed. Therefore, the resonance frequency of the mirror 123 in the tilt direction can be adjusted more easily.

  Further, according to the present embodiment, since the magnetic spring magnet 252 and the magnetic spring magnet 262 are provided on both the left and right sides, a substantially uniform drag can be applied to the left and right sides of the inner unit frame 11. it can. Therefore, the mirror 123 can be stably rotated in the tilt direction.

  Further, according to the present embodiment, since the suspension wires 19a to 19d are stretched in a straight line, they can be easily exchanged with ones having different spring constants. Therefore, the resonance frequency of the mirror 123 in the Pan direction can be easily adjusted.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made to the embodiments of the present invention other than the above.

  For example, in the above embodiment, the tilt magnets 151 and 161 are disposed on the inner unit frame 11 side and the tilt coils 221 and 231 are disposed on the actuator frame 21 side. As described above, the tilt coils 221 and 231 may be disposed on the inner unit frame 11 side, and the tilt magnets 151 and 161 may be disposed on the actuator frame 21 side. In this case, the magnets for magnetic springs 252 and 262 are attached to the inner unit frame 11 and rotate integrally with the inner unit frame 11 as the mirror 123 rotates in the tilt direction. As a result, as in the above embodiment, the magnetic spring magnets 252 and 262 can apply a drag force against the rotation in the tilt direction to the inner unit frame 11.

  In this case, since the tilt coils 221 and 231 are sandwiched between the tilt magnets 151 and 161 and the magnets for magnetic springs 252 and 262, the tilt coils 221 and 231 are applied as compared to the case of the above embodiment. The magnetic field becomes stronger.

  Referring to FIG. 19B, the driving force (electromagnetic force) for rotating the inner unit frame 11 is excited in the linear portion 221a of the tilt coil 221. In the state of FIG. 19B, the magnetic poles of the tilt magnet 151 and the magnetic spring magnet 252 are different at the position of the linear portion 221a. For this reason, a strong magnetic field is applied to the linear portion 221a, and a large driving force is excited in the linear portion 221a.

  When the inner unit frame 11 is rotated in the tilt direction and the magnetic spring magnet 252 and the tilt coil 221 are rotated as shown in FIG. 19C, some of the magnetic poles of the magnetic spring magnet 252 are the same as the tilt magnet 151. The magnetic field enters the magnetic pole, and the magnetic field becomes somewhat unstable at this portion. However, also in this case, since the magnetic poles of the tilt magnet 151 and the magnetic spring magnet 252 are different at the position of the linear portion 221a, a stable strong magnetic field is applied to the linear portion 221a. For this reason, a large driving force is excited in the linear portion 221a as in the case of FIG.

  In the configuration of FIG. 19A, the magnet for magnetic spring 252 corresponds to the first magnet recited in the claims, and the tilt magnet 151 corresponds to the second magnet recited in the claims. Equivalent to.

  In the case of the modification example 1, the distance between the magnetic spring magnet 252 and the tilt magnet 151 is larger than that in the above embodiment, and the applied magnetic field is weakened. Therefore, in order to generate a torque equivalent to that in the above embodiment, the distance between the magnetic spring magnet 252 and the tilt magnet 151 may be configured to be small.

  In the above-described embodiment, the magnetic spring magnets 252 and 262 are used for the rotation of the mirror 123 in the tilt direction. However, the magnetic spring magnet is used for the rotation of the mirror 123 in the pan direction. It may be used. In this case, for example, as shown in Modification 2 of FIG. 13A, a magnetic spring magnet 292 is attached above the pan shaft 12. At this time, when the mirror 123 rotates in the Pan direction, the pan coil 171 and the magnetic spring magnet 292 rotate integrally, and the pan magnet 131 does not rotate. Thus, as in the above embodiment, the magnetic spring magnet 292 can apply a drag force against the pan shaft 12 rotation, and the resonance frequency of the mirror 123 in the Pan direction can be adjusted.

  In the configuration of FIG. 20A, the inner unit frame 11 corresponds to the support portion described in the claims, and the pan shaft 12 corresponds to the movable portion described in the claims. Moreover, the magnet 292 for magnetic springs is equivalent to the 1st magnet as described in a claim, and the pan magnet 131 is equivalent to the 2nd magnet as described in a claim.

  In the above embodiment, the magnets for magnetic springs 252 and 262 are attached to the tilt shafts 25 and 26. However, as shown in Modification 3 in FIG. 20B, the actuator frame 21 is attached to the tilt magnet 151. It may be formed so as to extend to an opposing position, and a magnetic spring magnet 252 may be attached thereto. In this case, the tilt shaft 25 is configured to be shorter than the above embodiment. In the case of the modified example 3, the actuator frame 21 is easily increased in size as compared with the above embodiment, but the same effect as the above embodiment can be achieved.

  In the above embodiment, the magnetic spring magnets 252 and 262 are attached to the tilt shafts 25 and 26 via the magnetic spring magnet holders 251 and 261, but the magnetic spring magnet holders 251 and 261 are omitted. The magnet springs 252 and 262 may be directly attached to the tilt shafts 25 and 26.

  In the above embodiment, the magnets for magnetic springs 252 and 262 are provided on the tilt shafts 25 and 26, respectively, but may be provided only on one side of the tilt shaft. In this case, since the magnetic force of the magnet for the magnetic spring is applied only to the tilt shaft on one side, the balance when rotating in the tilt direction is slightly deteriorated, but a stable drag of the mirror 123 can be applied as in the above embodiment. it can.

  In the above embodiment, the magnetic spring magnets 252 and 262 are arranged so that the force that the magnetic spring magnet 252 attracts the tilt magnet 151 and the force that the magnetic spring magnet 262 attracts the tilt magnet 151 are balanced. Magnetic spring magnets 252 and 262 may be arranged so that the attractive force is biased to one side. As a result, a force for pulling the inner unit frame 11 is generated on either the left or right side, so that either the left or right bearing 11o (see FIG. 12) is applied to the magnetic spring magnet holder 251 or the magnetic spring magnet holder 262. Pressed. Therefore, the axial movement of the tilt shafts 25 and 26 of the inner unit frame 11 can be suppressed.

  In the above embodiment, the tilt magnets 151 and 161 and the magnets for magnetic springs 252 and 262 are divided into four regions, but may be divided into two regions.

  Further, in the above embodiment, the tilt magnets 151 and 161 and the magnets for magnetic springs 252 and 262 are circular, but those having a square shape may be used. Since the tilt magnets 151 and 161 and the magnetic spring magnets 252 and 262 rotate, it is preferable that the tilt magnets 151 and 161 and the magnetic spring magnets 252 and 262 have a circular shape as in the above embodiment.

  In the above embodiment, the suspension wires 19a to 19d having four circular sections are used to supply current to the pan coils 171, 181 and the LED 122. However, the number of suspension wires is limited to this. It is not a thing. For example, in the above embodiment, suspension wires that are not used for power feeding may be further arranged. Further, the suspension wires 19a to 19d may have a rectangular cross section.

  In the above embodiment, the diffusion type (wide directional type) LED 122 is used as the light source for diffusing the servo light. However, a non-diffusion type LED may be used. In this case, you may make it arrange | position the diffuser lens which has a light-diffusion effect | action on the light-projection side of LED which is not a diffusion type. Moreover, you may make it LED which is not a diffusion type covered with the cap which has a light-diffusion effect | action.

  Further, in the above embodiment, the mirror actuator 1 is configured such that the inner unit frame 11 rotates in the Tilt direction, and the mirror 123 rotates in the Pan direction with respect to the inner unit frame 11. The mirror actuator 1 may be configured such that the unit frame 11 rotates in the Pan direction and the mirror 123 rotates in the Tilt direction with respect to the inner unit frame 11.

  In addition, the embodiment of the present invention can be variously modified as appropriate within the scope of the technical idea shown in the claims.

1 ... Mirror actuator 10 ... Inner unit (movable part)
123 ... Mirror 151 ... Tilt magnet (first magnet, drive unit)
161: Tilt magnet (first magnet, drive unit)
20 ... Outer unit (support)
221: Tilt coil (coil, drive unit)
231... Tilt coil (coil, drive unit)
25 ... Tilt shaft (rotating axis)
251 ... Magnet holder for magnetic spring (holding member)
252 ... Magnet for magnetic spring (second magnet)
26 ... Tilt shaft (rotating axis)
261 ... Magnet holder for magnetic spring (holding member)
262 ... Magnet for magnetic spring (second magnet)
300 ... Laser radar 400 ... Projection unit (beam irradiation device)

Claims (7)

A support part;
A movable part that holds the mirror and is rotatably supported by the support part;
A magnetic member that is disposed on each of the support portion and the movable portion, and applies a magnetic force to the movable portion to pull the movable portion back to the setting position when the movable portion rotates from a predetermined setting position;
A mirror actuator comprising: The mirror actuator according to claim 1, wherein
The magnetic member is divided into a plurality of regions in the circumferential direction and a plurality of magnets in the circumferential direction so as to correspond to the first magnets having different magnetic poles in adjacent regions and the respective regions of the first magnet. A magnetic pole of each region, and a second magnet different from the magnetic pole of the region corresponding to the first magnet,
The first magnet is installed in the movable part so that the region of the first magnet is arranged around the rotation axis of the movable part,
When the movable part is in the set position, the second magnet is moved in such a manner that the region of the second magnet faces the corresponding region of the first magnet at a predetermined distance. Installed in the support,
A mirror actuator characterized by that. The mirror actuator according to claim 2,
A drive unit that drives the movable unit by electromagnetic force generated by applying a current to the coil;
At least one of the first magnet and the second magnet is included in the drive unit as means for applying a magnetic field to the coil.
A mirror actuator characterized by that. The mirror actuator according to claim 2 or 3,
A distance adjusting unit for adjusting a distance between the first magnet and the second magnet;
A mirror actuator characterized by that. The mirror actuator according to claim 4, wherein
The distance adjusting unit includes a screw part formed on a rotation shaft of the movable part, and a holding member that meshes with the screw part and holds the second magnet.
A mirror actuator characterized by that. A mirror actuator according to any one of claims 1 to 5;
A laser light source for supplying a laser beam to the mirror of the mirror actuator,
A beam irradiation apparatus characterized by that. A mirror actuator according to any one of claims 1 to 5;
A laser light source for supplying laser light to the mirror of the mirror actuator;
A light receiving portion for receiving the laser light reflected from the target area;
A detection unit for detecting an object in the target region based on an output from the light receiving unit;
Comprising
A laser radar characterized by that.

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