Programmable digital TDI EO/IR scanning focal plane array with multiple selectable TDI sub-banks
A TDI scanner including a dynamically programmable focal plane array including a two-dimensional array of detectors arranged in a plurality of columns and a plurality of rows, the array being divided into a plurality of banks separated from one another by gap regions, each bank including a plurality of sub-banks, and each sub-bank including at least one row of detectors, a ROIC coupled to the focal plane array and configured to combine in a TDI process outputs from detectors in each column of detectors in each sub-bank, and a controller configured to program the focal plane array to selectively and dynamically set characteristics of the focal plane array, the characteristics including a size and a location within the two-dimensional array of each of the plurality of sub-banks and the gap regions, the size corresponding to a number of rows of detectors included in the respective sub-bank or gap region.
1. A method of operating a Time Delay and Integration (TDI) scanning sensor that includes a focal plane array having a plurality of banks of imaging detectors, each bank divided into a plurality of sub-banks of the imaging detectors, the method comprising:
scanning a field of view of the sensor across a scene to be imaged;
collecting image data from each of the plurality of sub-banks;
analyzing the image data from each of the plurality of sub-banks to determine whether a sub-bank in the plurality of sub-banks has been contaminated by over-illumination from an illumination threat present in the scene to be imaged and identifying any contaminated sub-banks;
dynamically setting characteristics of the focal plane array, the characteristics including a location of at least one of the plurality of sub-banks, the location corresponding to locations of gap regions within the focal plane array;
shunting imaging detectors corresponding to the gap regions; and
performing a TDI process on the image data to produce an image of the scene, wherein the image data from the contaminated sub-banks is excluded from the TDI process.
2. The method of claim 1 , wherein analyzing the image data from each of the plurality of sub-banks includes comparing the image data from each sub-bank with the image data from each other sub-bank, and identifying a contaminated sub-bank based on differences in the comparison.
3. The method of claim 1 , further comprising dynamically reconfiguring a number of the plurality of sub-banks included in each of the plurality of banks during the scanning.
4. The method of claim 3 , further comprising dynamically configuring a gain state of at least one of the plurality of sub-banks during the scanning.
5. The method of claim 1 , wherein dynamically setting the characteristics of the focal plane array includes dynamically setting a size of at least one of the plurality of sub-banks, the size corresponding to a number of rows of imaging detectors included in the respective sub-bank.
6. The method of claim 1 , further comprising reprogramming at least one characteristic of the focal plane array.
7. The method of claim 6 , wherein reprogramming the at least one characteristic of the focal plan array includes reprogramming the at least one characteristic of the focal plane array within a time period corresponding to a line rate of the scanning.
8. The method of claim 1 , further comprising preventing excess charge over a saturation limit in at least one of the imaging detectors from being accumulated.
9. The method of claim 8 , wherein preventing the excess charge over the saturation limit includes preventing the excess charge with a charge drain.
10. The method of claim 1 , further comprising excluding saturated imaging detectors from the TDI process.
11. A method of operating a Time Delay and Integration (TDI) scanning sensor that includes a focal plane array having a plurality of banks of imaging detectors, each bank divided into a plurality of sub-banks of the imaging detectors, the method comprising:
scanning a field of view of the sensor across a scene to be imaged;
collecting image data from each of the plurality of sub-banks;
analyzing the image data from each of the plurality of sub-banks to determine whether a sub-bank in the plurality of sub-banks has been contaminated by over-illumination from an illumination threat present in the scene to be imaged and identifying any contaminated sub-banks, the analyzing including comparing the image data from each sub-bank with the image data from each other sub-bank and identifying a contaminated sub-bank based on differences in the comparison; and
performing a TDI process on the image data to produce an image of the scene, wherein the image data from the contaminated sub-banks is excluded from the TDI process.
12. The method of claim 11 , further comprising dynamically reconfiguring a number of the plurality of sub-banks included in each of the plurality of banks during the scanning.
13. The method of claim 12 , further comprising dynamically configuring a gain state of at least one of the plurality of sub-banks during the scanning.
14. The method of claim 11 , further comprising dynamically setting characteristics of the focal plane array.
15. The method of claim 14 , wherein dynamically setting the characteristics of the focal plane array includes dynamically setting a size of at least one of the plurality of sub-banks, the size corresponding to a number of rows of imaging detectors included in the respective sub-bank.
16. The method of claim 11 , further comprising reprogramming at least one characteristic of the focal plane array.
17. The method of claim 16 , wherein reprogramming the at least one characteristic of the focal plan array includes reprogramming the at least one characteristic of the focal plane array within a time period corresponding to a line rate of the scanning.
18. The method of claim 11 , further comprising preventing excess charge over a saturation limit in at least one of the imaging detectors from being accumulated.
19. The method of claim 18 , wherein preventing the excess charge over the saturation limit includes preventing the excess charge with a charge drain.
20. The method of claim 11 , further comprising excluding saturated imaging detectors from the TDI process.