System and method for x-ray compatible 2D streak camera for a snapshot multiframe imager

Patent metadata

Field	Value
Publication number	US-11240433-B2
Application number	US-202016857913-A
Country	US
Kind code	B2
Filing date	Apr 24, 2020
Priority date	Jun 20, 2019
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

The present disclosure is directed to a snapshot multiframe imager having an aperture element having at least one aperture, an adjacently positioned random mask, an imaging element and a computer. The random mask has a plurality of micron scale apertures and receives light passing through the aperture element, which represents the spatial information from the scene being imaged, and generates a plurality of image frames encoded in a spatial domain. The imaging element may operate in a drift-scan mode receives the encoded image frames and generates a streaked pattern of electrons representing a plurality of images of the scene at a plurality of different times. The computer analyzes the streaked pattern of electrons and mathematically reconstructs the plurality of images.

First claim

What is claimed is:

1. A snapshot, multiframe imaging system for imaging a scene, the system comprising:
a random aperture element having at least one aperture receiving light representing spatial information from the scene being imaged;
a random mask having a plurality of micron-scale apertures;
wherein the random mask is spaced apart from the random aperture element;
wherein the light passes through the random aperture element and impinges the random mask;
wherein the random mask generates a plurality of encoded image frames of the scene, the plurality of encoded image frames being encoded in a spatial domain;
an imaging element disposed adjacent the random mask, operating in a drift-scan mode, configured to receive the plurality of encoded image frames and generating from the plurality of encoded image frames a streaked pattern of electrons representing a plurality of images of the scene at a plurality of different times; and
a computer configured to analyze the streaked pattern of electrons and mathematically reconstruct the plurality of images.

2. The system of claim 1 , wherein the imaging element comprises a streak camera.

3. The system of claim 1 , wherein the imaging element comprises a charge coupled device (CCD).

4. The system of claim 1 , wherein the random aperture element comprises a plurality of random apertures formed therein.

5. The system of claim 4 , wherein the plurality of random apertures comprise random apertures on a micron-scale size.

6. The system of claim 4 , wherein the plurality of random apertures comprise apertures on a scale of 100s of microns.

7. The system of claim 1 , wherein the aperture element comprises a penumbra optic, and wherein the at least one aperture comprises a single aperture.

8. The system of claim 7 , wherein the single aperture of the penumbra optic has a dimension on a scale of 100s of microns.

9. The system of claim 1 , wherein the imaging element includes a streak camera, a photocathode and an image recording device, the imaging element configured to receive the plurality of encoded image frames and to use the photocathode to generate the streaked pattern of electrons representing the plurality of images, from photons received by the streak camera.

10. The system of claim 1 , wherein the imaging element comprises a streak camera having a slit aperture.

11. The system of claim 1 , further comprising a translation mechanism for translating the imaging element while photons are passing through the plurality of micron-scale apertures in the random mask.

12. The system of claim 4 , wherein the random aperture element creates a pseudo-Fourier plane by spreading out the spatial information from the scene being imaged over an increased area to increase the spatial information captured by the imaging element.

13. The system of claim 4 , wherein the plurality of encoded image frames are encoded using an objective function, and where the objective function is set forth below as:
f ( x )=½∥ y−Kx∥ 2 +λΦ( x ),

where ½∥y−Kx∥ 2 describes how well a reconstructed image fits data of the plurality of encoded image frames;
λ/Φ(x) describes a cost function for a reconstructed image that penalizes unlikely solutions,
“y” is an image collected with the imaging element,
“x” represents image frames to reconstruct from the image, and
“K” is a matrix comprising a streak operator, a random aperture convolution matrix, and a random mask matrix.

14. The system of claim 1 , further comprising a display for displaying the mathematically reconstructed images.

15. A snapshot, multiframe photography system for imaging a scene, the system comprising:
a random aperture element forming a plate, the plate having a plurality of randomly spaced apertures having dimensions in a range of microns to hundreds of microns in diameter;
wherein the random aperture element receives light representing spatial information from the scene being imaged;
a random mask having a plurality of micron-scale apertures,
wherein the random mask is spaced apart from the random aperture element,
wherein the light passes through the random aperture element and impinges the random mask, and
wherein the random mask generates a plurality of encoded image frames, the plurality of encoded image frames encoded in a spatial domain;
an imaging element disposed adjacent the random mask, including a photocathode, configured to operate in a drift-scan mode to receive the plurality of encoded image frames, and generating from the plurality of encoded image frames a streaked pattern of electrons representing a plurality of images of the scene at a plurality of different times; and
a computer configured to analyze the streaked pattern of electrons and mathematically reconstruct the plurality of images.

16. The system of claim 15 , wherein the imaging element comprises at least one of a streak camera or a charge coupled device.

17. The system of claim 16 , wherein:
the imaging element further comprises a streak camera, which includes an image recording device; and
the streak camera further includes a slit aperture.

18. The system of claim 15 , wherein the random aperture element creates a pseudo-Fourier plane by spreading out the spatial information from the scene being imaged over an increased area to increase the spatial information captured by the imaging element.

19. The system of claim 15 , wherein the plurality of encoded image frames are encoded using an objective function, and where the objective function is set forth below as:
f ( x )=½∥ y−Kx∥ 2 +λΦ( x ),

where ½∥y−Kx∥ 2 describes how well a reconstructed image fits data of the plurality of encoded image frames;
λ/Φ(x) describes a cost function for a reconstructed image that penalizes unlikely solutions,
“y” is an image collected with the imaging element,
“x” represents image frames to reconstruct from the image, and
“K” is a matrix comprising a streak operator, a random aperture convolution matrix, and a random mask matrix.

20. A method for performing multiframe photography to image a scene, the method comprising:
using a random aperture element having at least one aperture on a scale of microns to hundreds of microns in diameter, disposed adjacent a scene to be imaged;
using a random mask having a plurality of micron-scale apertures, spaced apart from the random aperture element, to receive light representing spatial information from the scene being imaged, wherein the light passes through the random aperture element and impinges the random mask;
using the random mask to generate a plurality of encoded image frames, the plurality of encoded image frames being encoded in a spatial domain;
using an imaging element disposed adjacent the random mask, and operating in a drift-scan mode, to receive the plurality of encoded image frames and to generate from the plurality of encoded image frames a streaked pattern of electrons representing a plurality of images of the scene at a plurality of different times; and
using a computer to analyze the streaked pattern of electrons and to mathematically reconstruct the plurality of images.

21. The method of claim 20 , wherein using a random aperture element comprises at least one of:
using a random aperture element having a plurality of apertures having dimensions on at least one of a micron-range or a range of hundreds of microns; or
using a penumbra optic having a single aperture.

Assignees

• L Livermore Nat Security Llc

Inventors

• Dayton Matthew S
• Field John E

Classifications

• H04N25/71

  Charge-coupled device [CCD] sensors; Charge-transfer registers specially adapted for CCD sensors · CPC title

• H04N23/6845 Primary

  by combination of a plurality of images sequentially taken · CPC title

• H04N23/30

  for generating image signals from X-rays · CPC title

• H04N25/00

  Circuitry of solid-state image sensors [SSIS]; Control thereof · CPC title

• H03M7/3062 Primary

  Compressive sampling or sensing · CPC title