VARIABLE MAGNIFICATION ACTIVE IMAGING SYSTEM

• US 20170214858A1
• Filed: 01/27/2016
• Published: 07/27/2017
• Est. Priority Date: 01/27/2016
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Keller, Sean D., Uyeno, Gerald P.
• Granted Patent: US 10,602,070 B2
• Time in Patent Office: Days
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 23/58 Means for changing the camera field of view without moving the camera body, e.g. nutating or panning of optics or image sensors
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/65 Control of camera operation in relation to power supply
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 25/44 by partially reading an SSIS array

Abstract

Imaging systems and a method of generating an image. One example of an imaging system includes a detection subsystem including a focal plane array (FPA) coupled to a read-out integrated circuit (ROIC), the ROIC being configured to activate a portion of the FPA in a selected pattern during an integration period, an optical scanning subsystem including an optical source and a waveguide, the waveguide being configured to direct optical radiation generated by the optical source within a field of view of the detection subsystem and over an area of a scene, the portion of the FPA activated in the selected pattern corresponding to the area of the scene, and an adaptive polymer lens assembly positioned at an aperture of the imaging system shared by the detection subsystem and the optical scanning subsystem, the adaptive polymer lens assembly being configured to adjust an optical magnification of the scene.

Claims

1. An imaging system comprising:

a detection subsystem including a focal plane array (FPA) coupled to a read-out integrated circuit (ROIC), the ROIC being configured to activate a portion of the FPA in a selected pattern during an integration period;

an optical scanning subsystem including an optical source and a waveguide, the waveguide being configured to direct optical radiation generated by the optical source within a field of view (FOV) of the detection subsystem and over an area of a scene to be imaged, the portion of the FPA activated in the selected pattern corresponding to the area of the scene to be imaged; and

an adaptive polymer lens assembly positioned at an aperture of the imaging system shared by the detection subsystem and the optical scanning subsystem, the adaptive polymer lens assembly being configured to adjust an optical magnification of the scene to be imaged.

2. The imaging system according to claim 1, wherein the FPA includes a plurality of unit cells and the selected pattern is a pattern of individual unit cells, and wherein the ROIC is configured to activate individually each unit cell of the plurality of unit cells in the portion of the FPA according to the pattern of individual unit cells.

3. The imaging system according to claim 2, wherein the waveguide is configured to direct the optical radiation synchronously over the area of the scene to be imaged that corresponds to the individually activated unit cells, and not over an area of the scene to be imaged that corresponds to inactive unit cells.

4. The imaging system according to claim 1, wherein the FPA includes a plurality of unit cells and the selected pattern includes a first group of unit cells and a second group of unit cells, the first group of unit cells being spatially separated from the second group of unit cells by inactive unit cells.

5. The imaging system according to claim 4, wherein the waveguide is configured to direct the optical radiation over at least the area of the scene to be imaged that corresponds to the first group of unit cells and the second group of unit cells during a single frame of the detection subsystem, and not over an area of the scene to be imaged that corresponds to the inactive unit cells.

6. The imaging system according to claim 5, wherein the ROIC is further configured to activate the first group of unit cells for a first duration, and activate the second group of unit cells for a second duration within the single frame of the detection subsystem.

7. The imaging system according to claim 1, further comprising a controller in electrical communication with the detection subsystem, the optical scanning subsystem, and the adaptive polymer lens assembly, wherein the controller is configured to dynamically adjust the selected pattern.

8. The imaging system according to claim 7, wherein the controller is configured to receive a user command specifying the area of the scene to be imaged, and dynamically adjust the selected pattern responsive to receiving the user command.

9. The imaging system according to claim 8, wherein the specified area of the scene to be imaged includes a section of the scene outside of the FOV of the detection subsystem, and wherein the adaptive polymer lens assembly is configured to automatically expand the FOV of the detection subsystem from a first FOV to a second FOV to include the specified area of the scene to be imaged.

10. The imaging system according to claim 1, wherein the optical radiation includes one of a fan beam and a spot beam, wherein the waveguide is further configured to control a width of beam divergence of the optical radiation along a first axis, and wherein the adaptive polymer lens assembly is further configured to control a width of beam divergence of the optical radiation along a second axis substantially perpendicular to the first axis.

11. The imaging system according to claim 1, wherein the selected pattern includes a plurality of groups of unit cells, each group being assigned a priority relative to other groups of the plurality, and wherein the waveguide and ROIC are synchronized such that the ROIC activates the groups of unit cells during the integration period based at least in part on the assigned priority, and the waveguide illuminates sections of the area of the scene to be imaged corresponding to the activated groups based at least in part on the assigned priority.

12. The imaging system according to claim 1, wherein the detection subsystem and the optical scanning subsystem are configured to operate in accordance with a search and track image acquisition and generation technique, wherein the waveguide and ROIC are synchronized such that waveguide scans the FOV of the detection subsystem during a searching mode of operation to identify a target, and during a tracking mode of operation illuminates an area of the scene to be imaged corresponding to the target.

13. The imaging system according to claim 1, wherein the waveguide is a solid-state liquid crystal waveguide, and wherein the optical source includes one of a visible light source, a short-wave infrared (SWIR) light source, a near infrared (NIR) light source, and a Laser light source.

14. A method of generating an image, the method comprising:

directing optical radiation generated by an optical source of an optical scanning subsystem over an area of a scene to be imaged to illuminate the area of the scene;

activating a portion of a focal plane array (FPA) of a detection subsystem in a selected pattern during an integration period of the FPA, the portion of the FPA corresponding to the area of the scene illuminated; and

adjusting an optical magnification of the scene to be imaged with an adaptive polymer lens assembly positioned at an aperture shared between the detection subsystem and optical scanning subsystem.

15. The method according to claim 14, wherein the selected pattern includes a pattern of individual unit cells of the FPA, and activating the portion of the FPA in the selected pattern includes activating individually each unit cell of the plurality of unit cells according to the pattern of individual unit cells.

16. The method according to claim 15, wherein directing optical radiation over the area of the scene to be imaged includes illuminating at least the area of the scene to be imaged that corresponds to the individually activated unit cells, and not an area of the scene that corresponds to inactive unit cells.

17. The method according to claim 14, wherein the selected pattern includes a first group of unit cells and a second group of unit cells, the first group of unit cells being spatially separated from the second group of unit cells by inactive unit cells, and wherein directing optical radiation over the area of the scene to be imaged includes illuminating at least the area of the scene to be imaged that corresponds to the first group of unit cells and the second group of unit cells.

18. The method according to claim 17, further comprising receiving a user command specifying the area of the scene to be imaged, wherein dynamically adjusting the selected pattern includes dynamically adjusting the selected pattern responsive to receiving the user command.

19. The method according to claim 18, wherein the specified area of the scene to be imaged includes a section of the scene outside of a field of view (FOV) of the detection subsystem, and wherein adjusting the optical magnification of the scene to be imaged includes automatically expanding the FOV of the detection subsystem from a first FOV to a second FOV to include the specified area of the scene to be imaged.

20. An imaging system comprising:

a focal plane array (FPA);

a read-out integrated circuit (ROIC) coupled to the FPA, the ROIC being configured to activate a portion of the FPA in a first selected pattern during a first integration period and activate the portion of the FPA in a second selected pattern during a second integration period;

an optical scanning subsystem including an optical source and a waveguide in electrical communication with the ROIC, the waveguide being configured to direct optical radiation generated by the optical source over a first area of a scene to be imaged that corresponds to the portion of the FPA activated in the first selected pattern and over a second area of the scene to be imaged that corresponds to the portion of the FPA activated in the second selected pattern; and

an adaptive polymer lens positioned at an aperture of the imaging system, the adaptive polymer lens assembly being configured to adjust an optical magnification of the scene to be imaged.