Variable scan rate image generation

Patent metadata

Field	Value
Publication number	US-9686487-B1
Application number	US-201414120147-A
Country	US
Kind code	B1
Filing date	Apr 30, 2014
Priority date	Apr 30, 2014
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

Variable scan rate image generation is disclosed. A scanning device scans a scene with a detector array at a first constant scan rate. Photon accumulation values are iteratively transferred from each set of detector elements in the detector array to an adjacent set of detector elements at a first transfer rate based on the first constant scan rate. Photon accumulation values of one set of the plurality of sets are iteratively read out at the first transfer rate. The first constant scan rate is accelerated to a second constant scan rate, and photon accumulation values are iteratively transferred from each set to an adjacent set at a second transfer rate based on the second constant scan rate, and photon accumulation values of the at least one set of the plurality of sets are iteratively read out at the second transfer rate.

First claim

What is claimed is:

1. A method, comprising:
scanning, by a scanning device, over a first period of time, a scene with a detector array comprising a plurality of sets of detector elements at a first constant scan rate;
iteratively, during the first period of time, transferring photon accumulation values from each set of detector elements to an adjacent set of detector elements at a first transfer rate that is based on the first constant scan rate, and iteratively reading out the photon accumulation values from at least one set of detector elements of the plurality of sets of detector elements at the first transfer rate;
accelerating the first constant scan rate to a second constant scan rate that differs from the first constant scan rate; and
iteratively, during a second period of time, transferring photon accumulation values from each set of detector elements to an adjacent set of detector elements at a second transfer rate that is based on the second constant scan rate, and iteratively reading out the photon accumulation values of the at least one set of the plurality of sets at the second transfer rate.

2. The method of claim 1 , further comprising:
while the first constant scan rate is accelerated to the second constant scan rate, iteratively transferring photon accumulation values from each set of detector elements to an adjacent set of detector elements at a changing transfer rate based on an acceleration from the first constant scan rate to the second constant scan rate, and iteratively reading out the photon accumulation values of the at least one set of detector elements at the changing transfer rate.

3. The method of claim 2 , wherein the acceleration is increasing.

4. The method of claim 2 , wherein the acceleration is decreasing.

5. The method of claim 1 , further comprising generating imagery of the scene based on the photon accumulation values read out from the at least one set of detector elements.

6. A method, comprising:
scanning, by a scanning device, over a first period of time, a scene with a detector array at a first constant scan rate, the detector array comprising a plurality of sets of detector elements, the detector elements in each set arranged along a same imaginary line and configured to quantify photons accumulated over a period of time;
while the detector array is scanning the scene at the first constant scan rate over the first period of time, iteratively signaling, by a controller, the detector array to transfer photon accumulation values accumulated in each set of the plurality of sets to an adjacent set of the plurality of sets at a first transfer rate based on the first constant scan rate, and for each iteration, reading out the photon accumulation values of at least one set of the plurality of sets at the first transfer rate;
accelerating, by the scanning device, the first constant scan rate to a second constant scan rate that differs from the first constant scan rate; and
during a second period of time, iteratively signaling, by the controller, the detector array to transfer the photon accumulation values accumulated in each set of the plurality of sets to an adjacent set of the plurality of sets at a second transfer rate based on the second constant scan rate, and for each iteration, reading out the photon accumulation values of at least one set of the plurality of sets at the second transfer rate.

7. The method of claim 6 , further comprising:
while the first constant scan rate is accelerated to the second constant scan rate, iteratively signaling, by the controller, the detector array to transfer in the downstream direction photon accumulation values accumulated in each set to an adjacent set at a changing rate based on an acceleration from the first constant scan rate to the second constant scan rate.

8. The method of claim 7 , wherein the acceleration is increasing.

9. The method of claim 7 , wherein the acceleration is decreasing.

10. The method of claim 6 , further comprising generating imagery of the scene based on the photon accumulation values read out from the at least one set.

11. The method of claim 10 , further comprising:
determining, by a target identification module based on the imagery, that a portion of the scene previously scanned contains an item of interest;
positioning, by the scanning device, the detector array with respect to a location within the scene in response to determining that the portion of the scene depicts the item of interest; and
rescanning the portion of the scene that contains the item of interest with the detector array at a scan rate that differs from a scan rate at which the portion of the scene was previously scanned.

12. The method of claim 10 , further comprising presenting the imagery on a display device.

13. An apparatus, comprising:
a detector array comprising a plurality of sets of detector elements;
a scanning device configured to scan a scene with the detector array; and
a controller configured to:
signal the scanning device to scan the scene with the detector array at a first constant scan rate over a first period of time;
iteratively signal the detector array to transfer photon accumulation values from each set of detector elements to an adjacent set of detector elements at a first transfer rate based on the first constant scan rate over the first period of time, and iteratively read out the photon accumulation values of at least one set of the plurality of sets at the first transfer rate;
signal the scanning device to accelerate the first constant scan rate to a second constant scan rate; and
iteratively signal the detector array to transfer photon accumulation values from each set of detector elements to an adjacent set of detector elements at a second transfer rate based on the second constant scan rate over a second period of time, and iteratively read out the photon accumulation values of the at least one set of the plurality of sets at the second transfer rate.

14. The apparatus of claim 13 , wherein the controller is further configured to:
while the first constant scan rate is accelerated to the second constant scan rate, iteratively signal the detector array to transfer photon accumulation values in each set of detector elements to an adjacent set of detector elements at a changing transfer rate based on an acceleration from the first constant scan rate to the second constant scan rate, and to iteratively read out the photon accumulation values of at the least one set of detector elements at the changing transfer rate.

15. The apparatus of claim 14 , wherein the acceleration is increasing.

16. The apparatus of claim 14 , wherein the acceleration is decreasing.

17. The apparatus of claim 13 , wherein the controller is further configured to generate imagery of the scene based on the photon accumulation values read out from the at least one set.

18. The apparatus of claim 13 , further comprising:
a target identification module coupled to the controller, and configured to make a determination that a portion of the scene previously scanned contains an item of interest; and
wherein the controller is further configured to:
position the detector array with respect to a location within the scene in response to the determination; and
signal the scanning device to rescan the portion of the scene that contains the item of interest with the detector array at a scan rate that differs from a scan rate at which the portion of the scene was previously scanned.

19. A method, comprising:
scanning a scene with a detector array at

Assignees

• Lockheed Corp

Inventors

• Fish Trisha
• Myers Mark T

Classifications

• B64D47/08 Primary

  Arrangements of cameras · CPC title

• H04N23/951 Primary

  by using two or more images to influence resolution, frame rate or aspect ratio · CPC title

• H04N25/768

  for time delay and integration [TDI] · CPC title

• H04N25/42

  by switching between different modes of operation using different resolutions or aspect ratios, e.g. switching between interlaced and non-interlaced mode · CPC title

• H04N23/60

  Control of cameras or camera modules · CPC title