Optical device

Patent metadata

Field	Value
Publication number	US-2020363630-A1
Application number	US-201816762174-A
Country	US
Kind code	A1
Filing date	Sep 4, 2018
Priority date	Nov 15, 2017
Publication date	Nov 19, 2020
Grant date	—

Abstract

In an optical device, when viewed from a first direction, first, second, third, and fourth movable comb electrodes are respectively disposed between a first support portion and a first end of a movable unit, between a second support portion and a second end of the movable unit, between a third support portion and the first end, and between a fourth support portion and the second end of the movable unit. The first and second support portions respectively include first and second rib portions formed so that the thickness of each of the first and second support portions becomes greater than the thickness of the first torsion bar. The third and fourth support portions respectively include third and fourth rib portions formed so that the thickness of each of the third and fourth support portions becomes greater than the thickness of the second torsion bar.

First claim

1 . An optical device comprising:
a base; a movable unit that includes an optical function unit; a first torsion bar that is disposed on one side of the movable unit in a first direction, and is connected to the base and the movable unit; a second torsion bar that is disposed on the other side of the movable unit in the first direction, and is connected to the base and the movable unit; a first support portion that is disposed on one side of the first torsion bar in a second direction perpendicular to the first direction, and is connected to the movable unit; a second support portion that is disposed on the other side of the first torsion bar in the second direction, and is connected to the movable unit; a third support portion that is disposed on the one side of the second torsion bar in the second direction, and is connected to the movable unit; a fourth support portion that is disposed on the other side of the second torsion bar in the second direction, and is connected to the movable unit; a first movable comb electrode that is provided to the first support portion, and includes a plurality of first movable comb fingers; a second movable comb electrode that is provided to the second support portion, and includes a plurality of second movable comb fingers; a third movable comb electrode that is provided to the third support portion, and includes a plurality of third movable comb fingers; a fourth movable comb electrode that is provided to the fourth support portion, and includes a plurality of fourth movable comb fingers; a first fixed comb electrode that is provided to the base, and includes a plurality of first fixed comb fingers which are disposed alternately with the plurality of first movable comb fingers; a second fixed comb electrode that is provided to the base, and includes a plurality of second fixed comb fingers which are disposed alternately with the plurality of second movable comb fingers; a third fixed comb electrode that is provided to the base, and includes a plurality of third fixed comb fingers which are disposed alternately with the plurality of third movable comb fingers; and a fourth fixed comb electrode that is provided to the base, and includes a plurality of fourth fixed comb fingers which are disposed alternately with the plurality of fourth movable comb fingers, wherein each of the first movable comb fingers and each of the first fixed comb fingers which are adjacent to each other face each other in the first direction, each of the second movable comb fingers and each of the second fixed comb fingers which are adjacent to each other face each other in the first direction, each of the third movable comb fingers and each of the third fixed comb fingers which are adjacent to each other face each other in the first direction, each of the fourth movable comb fingers and each of the fourth fixed comb fingers which are adjacent to each other face each other in the first direction, the first movable comb electrode is disposed between the first support portion and a first end of the movable unit on the one side in the second direction when viewed from the first direction, the second movable comb electrode is disposed between the second support portion and a second end of the movable unit on the other side in the second direction when viewed from the first direction, the third movable comb electrode is disposed between the third support portion and the first end of the movable unit when viewed from the first direction, the fourth movable comb electrode is disposed between the fourth support portion and the second end of the movable unit when viewed from the first direction, the first support portion includes a first rib portion that is formed so that the thickness of the first support portion in a third direction perpendicular to the first direction and the second direction becomes greater than the thickness of the first torsion bar in the third direction, the second support portion includes a second rib portion that is formed so that the thickness of the second support portion in the third direction becomes greater than the thickness of the first torsion bar in the third direction, the third support portion includes a third rib portion that is formed so that the thickness of the third support portion in the third direction becomes greater than the thickness of the second torsion bar in the third direction, and the fourth support portion includes a fourth rib portion that is formed so that the thickness of the fourth support portion in the third direction becomes greater than the thickness of the second torsion bar in the third direction.

2 . The optical device according to claim 1 ,
wherein the first support portion further includes a first main body portion to which the first movable comb electrode is provided, the second support portion further includes a second main body portion to which the second movable comb electrode is provided, the third support portion further includes a third main body portion to which the third movable comb electrode is provided, the fourth support portion further includes a fourth main body portion to which the fourth movable comb electrode is provided, and the first torsion bar, the first main body portion, the second main body portion, the second torsion bar, the third main body portion, and the fourth main body portion extend along the first direction.

3 . The optical device according to claim 2 ,
wherein the first support portion further includes a first connection portion that is connected to the first main body portion and the movable unit, and the first connection portion has a shape that is bent to be spaced apart from the first torsion bar, the second support portion further includes a second connection portion that is connected to the second main body portion and the movable unit, and the second connection portion has a shape that is bent to be spaced apart from the first torsion bar, the third support portion further includes a third connection portion that is connected to the third main body portion and the movable unit, and the third connection portion has a shape that is bent to be spaced apart from the second torsion bar, and the fourth support portion further includes a fourth connection portion that is connected to the fourth main body portion and the movable unit, and the fourth connection portion has a shape that is bent to be spaced apart from the second torsion bar.

4 . The optical device according to claim 1 ,
wherein the first torsion bar is connected to the movable unit in such a manner that curvatures of an outer edge of the first torsion bar and an outer edge of the movable unit are continuous when viewed from the third direction, and the second torsion bar is connected to the movable unit in such a manner that curvatures of an outer edge of the second torsion bar and an outer edge of the movable unit are continuous when viewed from the third direction.

5 . The optical device according to claim 1 , further comprising:
a fifth movable comb electrode that is provided to a portion including the first end in the movable unit, and includes a plurality of fifth movable comb fingers; a sixth movable comb electrode that is provided to a portion including the second end in the movable unit, and includes a plurality of sixth movable comb fingers; a fifth fixed comb electrode that is provided to the base, and includes a plurality of fifth fixed comb fingers which are disposed alternately with the plurality of fifth movable comb fingers; and a sixth fixed comb electrode that is provided to the base, and includes a plurality of sixth fixed comb fingers which are disposed alternately with the plurality of sixth movable comb fingers, wherein each of the fifth movable comb fingers and each of the fifth fixed

Assignees

• Hamamatsu Photonics Kk

Inventors

• Sugimoto Tatsuya
• Suzuki Tomofumi
• KOTANI Kyosuke

Classifications

• B81C2201/0198

  for making a masking layer · CPC title

• B81C2201/0174

  for making multi-layered devices, film deposition or growing · CPC title

• B81C2201/013

  Etching · CPC title

• B81C1/00555

  Achieving a desired geometry, i.e. controlling etch rates, anisotropy or selectivity (B81C1/00023 - B81C1/0019 take precedence) · CPC title

• B81B2201/042

  Micromirrors, not used as optical switches · CPC title