Electro-optical semi-transparent photonic up-converter

Patent metadata

Field	Value
Publication number	US-12567554-B2
Application number	US-202117185554-A
Country	US
Kind code	B2
Filing date	Feb 25, 2021
Priority date	Feb 25, 2021
Publication date	Mar 3, 2026
Grant date	Mar 3, 2026

Abstract

A night vision optical device includes an underlying device configured to be sensitive to light in a first spectrum, and to provide output light based on absorbing light in the first spectrum. The night vision optical device further includes a stacked device overlapping the underlying device. The stacked device includes one or more openings formed in the stacked device to form one or more transparent regions which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through to the underlying device. The stacked device is sensitive to light in a second spectrum. The stacked device outputs light in the first spectrum to the underlying device as a result of absorbing light in the second spectrum. Thus, the underlying device outputs light based both on light passing through the transparent regions and on light output by the stacked device.

First claim

What is claimed is:

1 . A night-vision optical device comprising:
an underlying detector sensitive to a first spectrum and configured to provide output based on absorbing light in the first spectrum; and a semiconductor stacked device disposed in an overlapping relationship with the underlying detector, the semiconductor stacked device comprising:
a collector layer including a two-dimensional array of photodiodes sensitive to a second spectrum,
an emitter layer including a two-dimensional array of light emitters that emit in the first spectrum,
a transport layer that electrically couples, on a one-to-one positional correspondence, individual photodiodes in the collector layer to coaxially aligned corresponding light emitters in the emitter layer, and
transparent regions formed as trenches through at least one of the collector layer, the transport layer, and the emitter layer, the transparent regions being transmissive to the first spectrum to transmit ambient first-spectrum light directly to the underlying detector,
wherein the semiconductor stacked device is configured to:
generate, from light in the second spectrum, electrical carriers in the collector layer and drive the coaxially aligned light emitters to emit in the first spectrum toward the underlying detector, and
permit concurrent transmission of ambient first-spectrum light through the trenches, such that the underlying detector receives in a single focal plane first-spectrum light corresponding to both ambient first-spectrum light and up-converted second-spectrum light with spatial registration preserved by the coaxial correspondence.

2 . The device of claim 1 , further comprising an optical coupling layer between the stacked device and the underlying detector, the optical coupling layer including a fiber-optic substrate and a fiber-optic faceplate bonded using index-matching adhesives, the optical coupling layer being configured to position output from the stacked device and input to the detector in a common image plane.

3 . The device of claim 2 , wherein the optical coupling layer comprises a lenslet array and/or planar optics in combination with the fiber-optic substrate.

4 . The device of claim 1 , wherein the emitter layer comprises OLED emitters emitting within 700-800 nm and the underlying detector comprises a GaAs photocathode image intensifier responsive in that band.

5 . The device of claim 1 , wherein the transport layer comprises controllable amplifier circuitry to adjust current delivered to the light emitters thereby controlling a ratio between ambient first-spectrum contribution and up-converted contribution.

6 . The device of claim 1 , wherein the collector layer comprises at least one of metamaterial plasmonic arrays, III-V, II-VI, or IV semiconductor photodiodes, graphene, or organic photodiodes.

7 . The device of claim 6 , wherein the at least one of the metamaterial plasmonic arrays, III-V, II-VI, or IV semiconductor photodiodes, graphene, or organic photodiodes are reverse-biased.

8 . The device of claim 1 , wherein the trenches are arranged in a checkerboard pattern defining sub-pixels such that each emitter is coaxially aligned with a corresponding photodiode across parallel planes.

9 . A method of operating a composite night-vision device comprising an underlying detector sensitive to a first spectrum and an overlapping stacked device as in claim 1 , the method comprising:
identifying, in an output image from the underlying detector, first pixels that are spatially aligned with the trenches and second pixels that are spatially aligned with regions lacking trenches; rendering the first pixels using a first color palette associated with ambient first-spectrum light and rendering the second pixels using a second color palette associated with up-converted second-spectrum light; and outputting a colorized image in which contributions from different spectrums are distinguished by hue while remaining spatially co-registered.

10 . The method of claim 9 , further comprising assigning the second color palette to indicate SWIR (900-1700 nm), MWIR (3-5 μm), or LWIR (8-12 μm) origin depending on the sensitivity of the stacked device.

11 . A composite device comprising:
an underlying detector sensitive to a first spectrum; a first stacked device as in claim 1 , the first stacked device sensitive to a second spectrum; and a second stacked device disposed over the first stacked device, the second stacked device being sensitive to a third spectrum, the second stacked device including transparent regions transmissive to the second spectrum such that third-spectrum light is up-converted by the second stacked device to second-spectrum light that passes through the transparent regions of the second stacked device and is received by the first stacked device for further up-conversion to the first spectrum, wherein the underlying detector forms a single-plane image comprising ambient first-spectrum light and up-converted light originating from the second and third spectrums.

12 . The composite device of claim 11 , wherein the second stacked device up-converts third-spectrum 1.7-3.0 μm signals into second-spectrum 900-1700 nm, and the first stacked device up-converts the second-spectrum into the first spectrum detectable by the underlying detector.

13 . A method of manufacturing a stacked device for use with an underlying detector sensitive to a first spectrum, the method comprising:
forming, in a semiconductor stack that includes a collector layer, a transport layer, and an emitter layer, active silicon islands for drive/control circuitry of the emitter layer; removing non-active silicon islands between the active silicon islands to form trenches that are transparent to the first spectrum; and selecting a pixel pitch such that the removal yields a stack transparency of at least 60% at a pitch of about 22.5 μm, or at least 75% at a pitch of about 36 μm, or at least 50% at a pitch of about 17.5 μm, wherein ambient first-spectrum light passes through the trenches to the underlying detector while up-converted first-spectrum light from the emitter layer is simultaneously delivered to the underlying detector.

14 . The method of claim 13 wherein the trenches are produced by a backside etch through silicon to buried oxide followed by a transparent backfill that preserves mechanical integrity while remaining transmissive to the first spectrum.

Assignees

• L3Harris Technologies Inc

Inventors

• Burnsed Jon D
• Becker Jacob J
• Lebeau James A

Classifications

• H01J2231/50005

  characterised by form of illumination · CPC title

• G02B23/125

  head-mounted · CPC title

• H01J2231/50015

  Light · CPC title

• G02B23/12

  with means for image conversion or intensification · CPC title

• H01J31/50 Primary

  Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output · CPC title