IMAGER

• US 20130016179A1
• Filed: 07/06/2012
• Published: 01/17/2013
• Est. Priority Date: 07/15/2011
• Status: Active Grant

• Current Assignee: Ziva Corporation
• Original Assignee: Ziva Corporation
• Inventors: Birkbeck, Aaron L., Husain, Anis, Ranalli, Eliseo
• Granted Patent: US 9,253,360 B2
• Time in Patent Office: Days
• US Class Current: 348/36
• CPC Class Codes: H04N 1/0408 Different densities of dots per unit length
• CPC Class Codes: H04N 1/113 using oscillating or rotating mirrors
• CPC Class Codes: H04N 1/195 the array comprising a two-dimensional array or a combination of two-dimensional arrays
• CPC Class Codes: H04N 2201/0081 Image reader H04N2201/0091 - H04N2201/0094 take precedence
• CPC Class Codes: H04N 2201/02493 Additional optical elements not otherwise provided for, e.g. filters, polarising plates, masks or apertures
• CPC Class Codes: H04N 2201/02495 Constructional details not otherwise provided for, e.g. for ease of assembly, allowing access to the scanning elements, integrated reinforcing members
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths

Abstract

Selected embodiments use a relatively small image detector and a scanning mirror to obtain effective performance of a larger image detector. An imager with folded optics captures images of different field positions of a field of view (FOV), and stitches the images together for a larger image of the FOV. The stitched image is processed to identify portions of interest within the larger image, for example, using a cuing algorithm. The portions of interest are scanned again to capture enhanced quality images using, for example, longer dwell time for enhanced contrast. Another image of the FOV or a part of the FOV is stitched together using the enhanced quality images.

Claims

1. An imaging method comprising steps of:

scanning a scene occupying at least a part of a field of view to obtain a plurality of standard quality sub-images of the scene, each standard quality sub-image of the plurality of standard quality sub-images covering less than the scene, the plurality of standard quality sub-images together covering the scene; and

combining the plurality of standard quality sub-images into a first stitched image of the scene;

wherein the step of scanning the scene is performed in a first spectral band with a scanner comprising folded optics.

2. An imaging method according to claim 1, further comprising at least one of storing the first stitched image, transmitting the first stitched image to an external system, and displaying the first stitched image.

3. An imaging method according to claim 2, wherein the scanner comprises a scanning mirror.

4. An imaging method according to claim 2, wherein the scanner comprises a micro-electro-mechanical system (MEMS) scanning mirror.

5. An imaging method according to claim 1, further comprising steps of:

identifying at least one portion of interest in the scene from the first stitched image; and

scanning the at least one portion of interest to obtain one or more enhanced quality sub-images of the at least one portion of interest, each enhanced quality sub-image of the one or more enhanced quality sub-images covering less than the scene, the one or more enhanced quality sub-images together covering the at least one portion of interest, the step of scanning the at least one portion of interest being performed in response to the step of identifying, the step of scanning the at least one portion of interest covering less than the scene.

wherein the step of scanning the at least one portion is performed in the first spectral band with the scanner comprising folded optics.

6. An imaging method according to claim 5, wherein the one or more enhanced quality sub-images comprise a plurality of enhanced quality sub-images, the method further comprising steps of:

combining the plurality of enhanced quality sub-images to obtain a second stitched image of at least a part of the scene; and

at least one of storing the second stitched image, transmitting the second stitched image to an external system, and displaying the second stitched image.

7. An imaging method according to claim 6, wherein the second stitched image is combined using at least some of the enhanced quality sub-images and at least some of the standard quality sub-images.

8. An imaging method according to claim 6, wherein the second stitched image is combined using the plurality of enhanced quality sub-images and the standard quality sub-images that do not correspond to the at least one portion of interest.

9. An imaging method according to claim 6, wherein the second stitched image is combined without using the standard quality sub-images of the plurality of standard quality sub-images.

10. An imaging method according to claim 6, wherein:

each standard quality sub-image of the plurality of standard quality sub-images is obtained using a first dwell duration;

each enhanced quality sub-image of the plurality of enhanced quality sub-images is obtained using a second dwell duration, the second dwell duration being longer than the first dwell duration.

11. An imaging method according to claim 10, wherein the step of identifying comprises applying a cuing algorithm to the first stitched image to recognize at least one object in the scene.

12. An imaging method according to claim 10, wherein the step of identifying is based on at least one of (1) viewing direction of a user to whom the first stitched image is displayed, and (2) express selection by the user.

13. An imaging method according to claim 10, wherein the step of identifying comprises step for identifying the at least one portion of interest in the first stitched image.

14. An imaging method according to claim 5, wherein the one or more enhanced quality sub-images comprise a plurality of enhanced quality sub-images, the method further comprising steps of:

combining the plurality of enhanced quality sub-images to obtain a second stitched image;

scanning at least a part of the scene in a second spectral band with the scanner comprising folded optics, to obtain a plurality of second band sub-images;

combining the plurality of second band sub-images into a third stitched image;

fusing the second stitched image and the third stitched image to obtain a fused image; and

at least one of storing the fused image, transmitting the fused image to an external system, and displaying the fused image.

15. An imaging method according to claim 14, wherein:

the first spectral band lies in visible part of electromagnetic spectrum; and

the second spectral band lies in infrared part of the electromagnetic spectrum.

16. An imager, comprising:

an optical subsystem comprising at least one image detector, folded optics, a controllable scanning mechanism, a control input, and a data output, wherein the controllable scanning mechanism is configured to direct light onto the at least one image detector through the folded optics, the light being incident on the controllable scanning mechanism from a range of field positions controllable by the control input, and the at least one image detector is configured to capture captured sub-images in one or more spectral bands and output the captured sub-images through the data output; and

a processor subsystem comprising a processor, a control interface circuit coupled to drive the control input, and an image reader interface circuit coupled to the data output to read the captured sub-images through the data output.

17. An imager according to claim 17, wherein the processor subsystem is configured to cause the optical subsystem to

scan, in a first spectral band of the one or more spectral bands, a scene occupying at least a part of a field of view to obtain a plurality of standard quality sub-images of the scene, each standard quality sub-image of the plurality of standard quality sub-images covering less than the scene, the plurality of standard quality sub-images together covering the scene;

and

combine the plurality of standard quality sub-images into a first stitched image of the scene.

18. An imager according to claim 17, wherein the processor subsystem is further configured to perform an action selected from the group consisting of store the first stitched image, transmit the first stitched image to an external system, and display the first stitched image.

19. An imager according to claim 18, wherein the controllable scanning mechanism comprises a scanning mirror.

20. An imager according to claim 18, wherein the controllable scanning mechanism comprises a micro-electro-mechanical system (MEMS) scanning mirror.

21. An imager according to claim 17, wherein the processor subsystem is further configured to:

identify at least one portion of interest in the scene from the first stitched image; and

after identifying the at least one portion, scan the at least one portion of interest to obtain one or more enhanced quality sub-images of the at least one portion of interest, each enhanced quality sub-image of the one or more enhanced quality sub-images covering less than the scene, the one or more enhanced quality sub-images together covering the at least one portion of interest, the one or more enhanced quality sub-images covering less than the scene.

22. An imager according to claim 21, wherein:

the one or more enhanced quality sub-images comprise a plurality of enhanced quality sub-images; and

the processor subsystem is further configured to

combine the plurality of enhanced quality sub-images to obtain a second stitched image of at least a part of the scene; and

at least one of store the second stitched image, transmit the second stitched image to an external system, and display the second stitched image.

23. An imager according to claim 22, wherein the processor subsystem is further configured to control dwell of the optical subsystem so that (1) each standard quality sub-image of the plurality of standard quality sub-images is obtained using a first dwell duration, and (2) each enhanced quality sub-image of the plurality of enhanced quality sub-images is obtained using a second dwell duration, the second dwell duration being longer than the first dwell duration.

24. An imager according to claim 23, wherein the processor subsystem is further configured to identify the at least one portion of interest by applying a cuing algorithm to the first stitched image to recognize at least one object in the scene.

25. An imager according to claim 23, wherein the processor subsystem is further configured to identify the at least one portion of interest based on a selection by a user.

26. An imager according to claim 21, wherein the at least one image detector is configured to capture sub-images in a first spectral band and in a second spectral band, the second spectral band being different from the first spectral band, the one or more enhanced quality sub-images comprise a plurality of enhanced quality sub-images, and the processor subsystem is further configured to:

combine the plurality of enhanced quality sub-images to obtain a second stitched image;

cause the optical subsystem to scan, in the second spectral band, at least a part of the scene, to obtain a plurality of second band sub-images;

combine the plurality of second band sub-images into a third stitched image; and

fuse the second stitched image and the third stitched image to obtain a fused image.

27. An imager according to claim 26, wherein:

the first spectral band lies in visible part of electromagnetic spectrum; and

the second spectral band lies in infrared part of the electromagnetic spectrum.