Light deflector, LiDAR device, and image forming apparatus
A light deflector includes a reflector having a reflecting surface, a movable part coupled to the reflector, a drive circuit configured to cause the movable part to deform so as to oscillate the reflector, a supporting unit having an opening in part; and a spring having a bending structure. The spring is disposed between the movable part and the supporting unit, the spring coupled to each of the movable part and the supporting unit.
1. A light deflector comprising:
a reflector having a reflecting surface;
a movable part coupled to the reflector;
a drive circuit configured to cause the movable part to deform so as to oscillate the reflector;
a frame including a first supporting unit and a second supporting unit, the frame being discontinuous in a region where the reflector is arranged; and
a spring having a meandering structure disposed between the movable part and each of the first supporting unit and the second supporting unit, the spring coupled to the movable part and each of the first supporting unit and the second supporting unit.
2. The light deflector according to claim 1 ,
wherein the spring is less rigid than the movable part in a direction of an oscillation axis of the reflector and is more rigid than the movable part in a direction orthogonal to the reflecting surface.
3. The light deflector according to claim 1 ,
wherein an opening is provided at one side of the reflector, and another opening is provided at the other side of the reflector in a direction orthogonal to a direction of an oscillation axis of the reflector.
4. The light deflector according to claim 3 ,
wherein the movable part has a meandering structure in which a plurality of movable beams is arranged in parallel and coupled to each other, and
wherein the drive circuit is a piezoelectric element disposed on each of the movable beams.
5. The light deflector according to claim 4 ,
wherein a longitudinal direction of the spring is the same direction as a longitudinal direction of each of the movable beams.
6. The light deflector according to claim 4 ,
wherein an angle formed by a longitudinal direction of the spring and a longitudinal direction of each of the movable beams is greater than 0° and less than 90°.
7. The light deflector according to claim 3 ,
wherein the movable part includes a plurality of movable parts, each of the movable parts including a torsion bar and a movable beam, and each torsion bar is coupled to the reflector and a corresponding one of the movable beams,
wherein the drive circuit is a piezoelectric element disposed on each of the movable beams.
8. The light deflector according to claim 7 ,
wherein a longitudinal direction of the spring is the same direction as a longitudinal direction of each of the movable beams.
9. The light deflector according to claim 7 ,
wherein an angle formed by a longitudinal direction of the spring and a longitudinal direction of each of the movable beams is greater than 0° and less than 90°.
10. The light deflector according to claim 1 ,
wherein an opening is provided at one side of the reflector, and another opening is provided at the other side of the reflector in a direction of an oscillation axis.
11. The light deflector according to claim 1 ,
wherein the spring includes a plurality of springs arranged symmetrically about an oscillation axis of the reflector.
12. A LiDAR device comprising the light deflector according to claim 1 .
13. The light deflector according to claim 1 ,
wherein the spring is thicker than the movable part in a direction orthogonal to the reflecting surface.
14. The light deflector according to claim 1 ,
wherein the first supporting unit and the second supporting unit are discontinuous across the reflector in a direction of an oscillation axis of the reflector.
15. The light deflector according to claim 1 ,
wherein the spring is narrower than the movable part in a direction of an oscillation axis of the reflector.
16. The light deflector according to claim 1 ,
wherein the first supporting unit and the second supporting unit face each other across the reflector.