Optical sensors

Patent metadata

Field	Value
Publication number	US-9684162-B2
Application number	US-201615090916-A
Country	US
Kind code	B2
Filing date	Apr 5, 2016
Priority date	Apr 9, 2015
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

An optical sensor includes an array of pixels configured to convert photons into electrons for forming an image. A tunable filter assembly is optically connected to the array of pixels for passing an adjustable bandwidth of photons to the array of pixels. The tunable filter assembly includes a first mirror defining an optical axis and a second mirror spaced apart from the first mirror along the optical axis. A first electrode is mechanically connected to the first mirror and a second electrode is fixed relative to the second mirror. The first and second electrodes are positioned relative to one another to adjust the position of the first mirror with respect to the second mirror when a voltage is applied across the first and second electrodes to tune the spectral bands being passed through the filter assembly to the array of pixels.

First claim

What is claimed is:

1. An optical sensor comprising:
an array of pixels configured to convert photons into electrons for forming an image; and
a tunable filter assembly optically connected to the array of pixels for passing an adjustable bandwidth of photons to the array of pixels, wherein the tunable filter assembly includes:
a first mirror defining an optical axis;
a second mirror spaced apart from the first mirror along the optical axis; and
a first electrode mechanically connects to the first mirror; and
a second electrode fixed relative to the second mirror, wherein the first and second electrodes are positioned relative to one another to adjust the position of the first mirror with respect to the second mirror when a voltage is applied across the first and second electrodes to tune the spectral bands being passed through the filter assembly to the array of pixels.

2. An optical sensor as recited in claim 1 , wherein the tunable filter assembly is one of a plurality of filter assemblies arranged in rows over the array of pixels, wherein each filter assembly is optically connected to respective sections of the array of pixels to pass a separate adjustable bandwidth to one of the respective sections to create high-resolution, long-range multi-spectral imagery with tunable spectral bands.

3. An optical sensor as recited in claim 1 , wherein the tunable filter assembly is one of three filter assemblies arranged in rows over the array of pixels, wherein each filter assembly is optically connected to respective sections of the array of pixels to pass a separate adjustable bandwidth to one of the respective sections to create high-resolution, long-range multi-spectral imagery with tunable spectral bands.

4. An optical sensor as recited in claim 1 , wherein the tunable filter assembly includes a plurality of electrical bond pads spaced apart along the array of pixels electrically connected to the first electrode to supply an even voltage to the first electrode.

5. An optical sensor as recited in claim 1 , wherein the adjustable bandwidth of the tunable filter assembly is within at least one of a SWIR, NIR, MWIR, LWIR, or visible band.

6. An optical sensor as recited in claim 1 , wherein the tunable filter assembly includes a frame operatively connected between the first mirror and the first electrode, wherein the first electrode is connected to a first portion of the frame and the first mirror is connected to a second portion of the frame, wherein the frame includes a plurality of spaced apart bridges connecting between the first and second portions of the frame to suspend the first mirror and the second portion of the frame over the second mirror.

7. An optical sensor as recited in claim 6 , wherein the tunable filter assembly includes a plurality of spaced apart posts extending between the first and second electrodes to separate the first electrode apart from the second electrode in a direction parallel to the optical axis.

8. An optical sensor as recited in claim 7 , wherein each of the bridges of the frame connect between the first and second portions of the frame midway between a respective pair of the posts.

9. An optical sensor as recited in claim 8 , wherein the posts are positioned to allow flexure of the first electrode and the first portion of the frame in a direction parallel to the optical axis when a voltage is applied, thereby adjusting the position of the first mirror along the optical axis and tuning the adjustable bandwidth passing through the tunable filter assembly.

10. An optical sensor as recited in claim 1 , wherein the array of pixels and the tunable filter assembly are cryogenically cooled.

Assignees

• Goodrich Corp

Inventors

• Whitcomb Kevin J
• Basedow Robert

Classifications

• H04N23/55

  Optical parts specially adapted for electronic image sensors; Mounting thereof · CPC title

• G01J2003/2806

  Array and filter array · CPC title

• G01J3/2823

  Imaging spectrometer · CPC title

• G02B7/008

  with means for compensating for changes in temperature or for controlling the temperature; thermal stabilisation · CPC title

• G01J2003/2826

  Multispectral imaging, e.g. filter imaging · CPC title