Optical reflection element
View Patent ↗An optical reflecting device includes a mirror part, a pair of joints, a pair of vibration parts, a plurality of driving parts, and a fixed part. Each of the joints has a first end connected to respective one the facing positions to each other on the mirror part and a second end opposite to the first end, and extends along a first axis. Each of the vibration parts has a central portion connected to the second end of respective one of the joints. A plurality of driving parts are disposed in each of the pair of vibration parts, and rotate the mirror part. Both ends of each of the pair of vibration parts are connected to the fixed part. The beam width defined as the length of each of the joints in a direction orthogonal to the first axis is greater than the beam width of each of the pair of vibration parts.
1. An optical reflecting device comprising: a mirror part;
a pair of joints each having a first end connected to respective one of facing positions to each other on the mirror part, and a second end opposite to the first end, and extending along a first axis;
a pair of vibration parts each having a central portion connected to the second end of respective one of the joints, and extending along a second axis orthogonal to the first axis;
a plurality of driving parts disposed in each of the pair of vibration parts and configured to rotate the mirror part; and
a fixed part directly connected to both ends of each of the pair of vibration parts, wherein each of the pair of vibration parts linearly extends across the both ends directly connected to the fixed part,
a beam width of each of the joints is greater than a beam width of each of the pair of vibration parts, where the beam width of each of the joints is defined as a length along the second axis and the beam width of each of the pair of vibration parts is defined as a length along the first axis.
2. The optical reflecting device according to claim 1 ,
wherein each of the pair of vibration parts includes a pair of beam parts between the central portion connected to each of the joints and the fixed part,
each of the pair of beam parts has a curved shape, and
the beam width of each of the pair of vibration parts is defined as a length between an outer circumference and an inner circumference of the curved shape.
3. The optical reflecting device according to claim 2 , wherein each of the beam parts is formed of a first curved part closer to the fixed part and a second curved part closer to the central portion.
4. The optical reflecting device according to claim 3 , wherein a curvature radius of the first curved part is smaller than a curvature radius of the second curved part.
5. The optical reflecting device according to claim 4 , wherein the curvature radius of the second curved part is different at a side closer to the first curved part from at a side closer to each of the joints.
6. The optical reflecting device according to claim 3 , wherein a curved direction of the first curved part is different from a curved direction of the second curved part.
7. The optical reflecting device according to claim 6 , wherein a curvature radius of the first curved part is smaller than a curvature radius of the second curved part.
8. The optical reflecting device according to claim 7 , wherein the curvature radius of the second curved part is different at a side closer to the first curved part from at a side closer to each of the joints.
9. The optical reflecting device according to claim 3 , wherein each of the driving parts is formed on the second curved part.
10. The optical reflecting device according to claim 1 , wherein each of the driving parts is formed by sequentially stacking a lower electrode film, a piezoelectric film, and an upper electrode film.
11. The optical reflecting device according to claim 1 , wherein a monitor part is formed in a boundary between the fixed part and each of the vibration parts.
12. The optical reflecting device according to claim 1 , wherein the beam width of each of the joints is greater than a beam thickness of each of the joints, the beam thickness being defined as a length of each of the joints in a direction orthogonal to a plane formed of the first axis and a second axis orthogonal to the first axis.