Fabry-perot interference filter

Patent metadata

Field	Value
Publication number	US-2016370573-A1
Application number	US-201414901732-A
Country	US
Kind code	A1
Filing date	Jun 24, 2014
Priority date	Jul 2, 2013
Publication date	Dec 22, 2016
Grant date	—

Abstract

A Fabry-Perot interference filter 10 A includes a first mirror 31 ; a second mirror 41 being opposite to the first mirror 31 with a gap S therebetween; a first electrode 17 formed in the first mirror 31 to surround a light transmission region 11 ; a second electrode 18 formed in the first mirror 31 to include the light transmission region 11 ; and a third electrode 19 formed in the second mirror 41 to be opposite to the first electrode 17 and the second electrode 18 and connected to the same potential as the second electrode 18 . The second electrode 18 is positioned at the side of the third electrode 19 or the opposite side thereof with respect to the first electrode 17 in an opposite direction D where the first mirror 31 and the second mirror 41 are opposite each other.

First claim

1 . A Fabry-Perot interference filter comprising:
a first mirror; a second mirror being opposite to the first mirror with a gap therebetween; a first electrode formed in the first mirror to surround a light transmission region; a second electrode formed in the first mirror to include the light transmission region; and a third electrode formed in the second mirror to be opposite to the first electrode and the second electrode and connected to the same potential as the second electrode, wherein the second electrode is positioned at the side of the third electrode or the opposite side thereof with respect to the first electrode in an opposite direction where the first mirror and the second mirror are opposite each other.

2 . The Fabry-Perot interference filter according to claim 1 , wherein the second electrode is positioned at the opposite side of the third electrode with respect to the first electrode in the opposite direction.

3 . The Fabry-Perot interference filter according to claim 2 , wherein the second electrode is isolated from the gap by a dielectric layer configuring the first mirror.

4 . The Fabry-Perot interference filter according to claim 2 , wherein the second electrode is exposed to the gap in a recessed portion provided in the first mirror.

5 . The Fabry-Perot interference filter according to claim 1 , further comprising:
a wiring electrically connecting the second electrode and the third electrode, wherein the wiring has a first wiring portion extending from the second electrode to the outside of the second electrode along a direction vertical to the opposite direction and a second wiring portion extending from the first wiring portion to the side of the third electrode along the opposite direction.

6 . The Fabry-Perot interference filter according to claim 1 , further comprising:
a substrate supporting the first mirror and the second mirror, wherein the first mirror is disposed on one side of the substrate, and the second mirror is disposed on the one side of the first mirror with the gap therebetween.

7 . The Fabry-Perot interference filter according to claim 1 ,
wherein each of the first mirror and the second mirror has a polysilicon layer and a silicon nitride layer, and the first electrode, the second electrode, and the third electrode are doped regions of impurities in the polysilicon layer.

8 . The Fabry-Perot interference filter according to claim 7 , wherein the polysilicon layer is a layer of amorphous silicon polycrystallized by annealing.

Assignees

• Hamamatsu Photonics Kk

Inventors

• Shibayama Katsumi
• Kasahara Takashi
• Hirose Masaki
• Kawai Toshimitsu

Classifications

• G02B26/001 Primary

  based on interference in an adjustable optical cavity (interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26) · CPC title

• G01J3/26

  using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters · CPC title