MIRROR ACTUATOR, BEAM IRRADIATION DEVICE, AND LASER RADAR
A mirror actuator includes: a base; a first rotation portion that is supported on the base so as to be rotatable about a first rotation axis; a second rotation portion that is supported on the first rotation portion so as to be rotatable about a second rotation axis perpendicular to the first rotation axis; a mirror disposed at the second rotation portion; a first drive portion that rotates the first rotation portion around the first rotation axis; and a second drive portion that rotates the second rotation portion around the second rotation axis. The second drive portion has a coil part and a magnet part applying a magnetic field to the coil part. One of the coil part and the magnet part is disposed at the first rotation portion, and the other is disposed at the second rotation portion.
1 . A mirror actuator, comprising:
a base;
a first rotation portion that is supported on the base so as to be rotatable about a first rotation axis;
a second rotation portion that is supported on the first rotation portion so as to be rotatable about a second rotation axis perpendicular to the first rotation axis;
a mirror disposed at the second rotation portion;
a first drive portion that rotates the first rotation portion around the first rotation axis; and
a second drive portion that rotates the second rotation portion around the second rotation axis, wherein
the second drive portion has a coil part and a magnet part applying a magnetic field to the coil part, and
one of the coil part and the magnet part is disposed at the first rotation portion, and the other is disposed at the second rotation portion.
2 . The mirror actuator according to claim 1 , wherein
the second rotation portion includes a shaft part that is supported on the first rotation portion so as to be rotatable about the second rotation axis,
the mirror is attached to the shaft part,
the coil part is disposed at one of the shaft part and the first rotation portion, and
the magnet part is disposed at the other of the shaft part and the first rotation portion.
3 . The mirror actuator according to claim 2 , wherein
the magnet part includes a magnet with divided magnetic poles around the second rotation axis,
the coil part includes a plurality of coils including straight portions radially extending from the second rotation axis, the plurality of coils being formed such that the adjacent straight portions are opposed to one of the magnetic poles of the magnet, and
the coils and the magnet are arranged at predetermined intervals in a direction parallel to the second rotation axis.
4 . The mirror actuator according to claim 3 , wherein the magnet part is formed such that an outer periphery thereof has a circular shape centered at the second rotation axis.
5 . The mirror actuator according to claim 1 , wherein
the coil part is disposed at the second rotation portion, and
the magnet part is disposed at the first rotation portion.
6 . A beam irradiation device, comprising:
a mirror actuator; and
a laser light source that supplies laser light to a mirror of the mirror actuator, wherein
the mirror actuator includes:
a base;
a first rotation portion that is supported on the base so as to be rotatable about a first rotation axis;
a second rotation portion that is supported on the first rotation portion so as to be rotatable about a second rotation axis perpendicular to the first rotation axis;
a mirror disposed at the second rotation portion;
a first drive portion that rotates the first rotation portion around the first rotation axis; and
a second drive portion that rotates the second rotation portion around the second rotation axis, wherein
the second drive portion has a coil part and a magnet part applying a magnetic field to the coil part, and
one of the coil part and the magnet part is disposed at the first rotation portion, and the other is disposed at the second rotation portion.
7 . The beam irradiation device according to claim 6 , wherein
the second rotation portion includes a shaft part that is supported on the first rotation portion so as to be rotatable about the second rotation axis,
the mirror is attached to the shaft part,
the coil part is disposed at one of the shaft part and the first rotation portion, and
the magnet part is disposed at the other of the shaft part and the first rotation portion.
8 . The beam irradiation device according to claim 7 , wherein
the magnet part includes a magnet with divided magnetic poles around the second rotation axis,
the coil part includes a plurality of coils including straight portions radially extending from the second rotation axis, the plurality of coils being formed such that the adjacent straight portions are opposed to one of the magnetic poles of the magnet, and
the coils and the magnet are arranged at predetermined intervals in a direction parallel to the second rotation axis.
9 . The beam irradiation device according to claim 8 , wherein the magnet part is formed such that an outer periphery thereof has a circular shape centered at the second rotation axis.
10 . The beam irradiation device according to claim 6 , wherein
the coil part is disposed at the second rotation portion, and
the magnet part is disposed at the first rotation portion.
11 . A laser radar, comprising:
a mirror actuator;
a laser light source that supplies laser light to a mirror of the mirror actuator;
a light-receiving portion that receives the laser light reflected from a target region; and
a detection portion that detects an object in the target region based on an output from the light-receiving portion, wherein
the mirror actuator includes:
a base;
a first rotation portion that is supported on the base so as to be rotatable about a first rotation axis;
a second rotation portion that is supported on the first rotation portion so as to be rotatable about a second rotation axis perpendicular to the first rotation axis;
a mirror disposed at the second rotation portion;
a first drive portion that rotates the first rotation portion around the first rotation axis; and
a second drive portion that rotates the second rotation portion around the second rotation axis, wherein
the second drive portion has a coil part and a magnet part applying a magnetic field to the coil part, and
one of the coil part and the magnet part is disposed at the first rotation portion, and the other is disposed at the second rotation portion
12 . The laser radar according to claim 11 , wherein
the second rotation portion includes a shaft part that is supported on the first rotation portion so as to be rotatable about the second rotation axis,
the mirror is attached to the shaft part,
the coil part is disposed at one of the shaft part and the first rotation portion, and
the magnet part is disposed at the other of the shaft part and the first rotation portion.
13 . The laser radar according to claim 12 , wherein
the magnet part includes a magnet with divided magnetic poles around the second rotation axis,
the coil part includes a plurality of coils including straight portions radially extending from the second rotation axis, the plurality of coils being formed such that the adjacent straight portions are opposed to one of the magnetic poles of the magnet, and
the coils and the magnet are arranged at predetermined intervals in a direction parallel to the second rotation axis.
14 . The laser radar according to claim 13 , wherein the magnet part is formed such that an outer periphery thereof has a circular shape centered at the second rotation axis.
15 . The laser radar according to claim 11 , wherein
the coil part is disposed at the second rotation portion, and
the magnet part is disposed at the first rotation portion.