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A two-dimensional focal plane array (FPA) is divided into sub-arrays of rows and columns of pixels, each sub-array being responsive to light energy from a target object which has been separated by a spectral filter or other spectrum dividing element into a predetermined number of spectral bands. The

A two-dimensional focal plane array (FPA) is divided into sub-arrays of rows and columns of pixels, each sub-array being responsive to light energy from a target object which has been separated by a spectral filter or other spectrum dividing element into a predetermined number of spectral bands. There is preferably one sub-array on the FPA for each predetermined spectral band. Each sub-array has its own read out channel to allow parallel and simultaneous readout of all sub-arrays of the array. The scene is scanned onto the array for simultaneous imaging of the terrain in many spectral bands. Time Delay and Integrate (TDI) techniques are used as a clocking mechanism within the sub-arrays to increase the signal to noise ratio (SNR) of the detected image. Additionally, the TDI length (i.e., number of rows of integration during the exposure) within each sub-array is adjustable to optimize and normalize the response of the photosensitive substrate to each spectral band. The array provides for parallel and simultaneous readout of each sub-array to increase the collection rate of the spectral imagery. All of these features serve to provide a substantial improvement in the area coverage of a hyperspectral imaging system while at the same time increasing the SNR of the detected spectral image.

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1. An imaging system comprising, in combination:an electro-optical imaging array arranged as a plurality of rows and columns of individual pixel elements, said array organized into a plurality of sub-arrays of rows of said pixels, each sub-array being responsive to incident radiation from a scene of

1. An imaging system comprising, in combination:an electro-optical imaging array arranged as a plurality of rows and columns of individual pixel elements, said array organized into a plurality of sub-arrays of rows of said pixels, each sub-array being responsive to incident radiation from a scene of interest;a multi-spectral or hyperspectral filter placed in registry with said electro-optical imaging array, said filter defining a plurality of individual filter bands, said filter bands arranged in optical registry with said sub-arrays whereby each of said sub-arrays receives radiation passing through one of said individual filter bands;a scanning device directing radiation from said scene of interest onto said imaging array, said array and scanning device constructed and arranged such that as said scene of interest is scanned over said array a given point in said scene of interest is sequentially imaged by each of said sub-arrays; andclocking circuitry for said imaging array for clocking individual pixel elements in each of said sub-arrays in a direction and at a rate to thereby improve the signal to noise ratio of imagery from said array. 2. The system of claim 1, wherein said clocking circuitry comprises time delay and integrate (TDI) circuitry clocking said individual pixel elements in each of said arrays in a column direction. 3. The system of claim 1, wherein said clocking circuitry further comprises two-dimensional clocking circuitry for transferring pixel information in row and column direction to thereby 1) increase the signal to noise ratio of said array and 2) to compensate for relative motion of said array with respect to said scene of interest. 4. The system of claim 1, wherein the clocking of said sub-arrays varies among said sub-arrays depending on the spectral response of the material forming said sub-arrays. 5. The system of claim 4, wherein each of said sub-arrays has separate and variable clocking of pixels in the column direction depending on the spectral responsiveness of the material forming said sub-array. 6. The system of claim 1, wherein the clocking of said sub-arrays changes dynamically depending on the spectral content of incident radiation. 7. The system of claim 1, wherein the number of pixels in said sub-arrays varies in the column direction depending on the spectral response of the material forming said sub-arrays. 8. The system of claim 1, wherein said array comprises a wafer scale two-dimensional charge-coupled device. 9. The system of claim 1, wherein each of said sub-arrays is separated from an adjacent sub-array by an output transfer register. 10. The system of claim 9, wherein said output transfer register extends across the entire width of said array, wherein said array comprises a plurality of sub-arrays each extending in the row direction and across the entire width of said array, and wherein during an exposure of said array each sub-array simultaneously images a different portion of the scene of interest and the spectral content of the entire scene of interest is captured by scanning said scene of interest across all of said sub-arrays. 11. The system of claim 1, wherein the system comprises an aerial reconnaissance system for installation in a reconnaissance vehicle and wherein said system further comprises a mechanism for providing forward motion compensation for imagery generated by said array due to forward motion of said reconnaissance vehicle relative to said scene of interest. 12. The system of claim 1, wherein said filter further comprises a covering window for said array. 13. The system of claim 1, wherein said filter defines N separate filter bands and wherein said array further comprises N sub-arrays, and wherein N is an integer greater than or equal to 4. 14. The system of claim 1, wherein said array is sensitive to infra-red radiation and generates multi-spectral or hyperspectral imagery in the infra-red band. 15. The system of claim 14, wherein said array comprises a Mercu ry Cadmium Telluride focal plane array. 16. The system of claim 1, wherein said array comprises a charge-coupled device and wherein said array generates hyperspectral or multi-spectral imagery in the visible band. 17. The system of claim 1, wherein each of said sub-arrays has its own read out channel to allow parallel and simultaneous readout of all sub-arrays of the array. 18. The system of claim 1, wherein each of said sub-arrays has its own read out channel to allow parallel and simultaneous readout of all sub-arrays of the array. 19. The system of claim 1, wherein said array comprises a hybrid array incorporating a CMOS readout structure. 20. The system of claim 1, wherein said array comprises a CMOS detector. 21. The system of claim 1, wherein said array comprises a photosensitive material constructed from Indium Antimonide. 22. An imaging system comprising, in combination:an electro-optical imaging array arranged as a plurality of rows and columns of individual pixel elements, said array organized into a plurality of sub-arrays of rows of said pixels, each sub-array being responsive to incident radiation from a scene of interest;a spectral filter arranged relative to said array simultaneously directing radiation in a plurality of different spectral bands for different portions of a scene of interest onto said array, said spectral filter and sub-arrays arranged in optical registry with one another whereby each of said sub-arrays receives radiation in one of said individual bands;a scanning device directing radiation from said scene of interest onto said imaging array, said array and scanning device constructed and arranged such that as said scene of interest is scanned over said array a given point in said scene of interest is sequentially imaged by each of said sub-arrays; andclocking circuitry for said imaging array clocking said individual pixel elements in each of said sub-arrays in a direction and at a rate to thereby increase the signal to noise ratio of said array. 23. The system of claim 22, wherein said clocking circuitry comprises time delay and integrate (TDI) circuitry clocking said individual pixel elements in each of said arrays in a column direction. 24. The system of claim 23, wherein said clocking circuitry comprises two-dimensional clocking circuitry for transferring pixel information in row and column directions to thereby 1) increase the signal to noise ratio of said array and 2) to compensate for relative motion of said array with respect to said scene of interest. 25. The system of claim 24, wherein the clocking of said sub-arrays varies among said sub-arrays depending on the spectral response of the material forming said sub-arrays. 26. The system of claim 22, wherein the clocking of said sub-arrays changes dynamically depending on the spectral content of incident radiation. 27. The system of claim 22, wherein the number of pixels in said sub-arrays varies in the column direction depending on the spectral response of the material forming said sub-arrays. 28. The system of claim 22, wherein said array comprises a wafer scale two dimensional charge-coupled device. 29. The system of claim 22, wherein each of said sub-arrays is separated from an adjacent sub-array by an output transfer register. 30. The system of claim 29, wherein said output transfer register extends across the entire width of said array, wherein said array comprises a plurality of sub-arrays each extending in the row direction and across the entire width of said array, and wherein during an exposure of said array each sub-array simultaneously images a different portion of the scene of interest and the spectral content of the entire scene of interest is captured by scanning said scene of interest across all of said sub-arrays. 31. The system of claim 22, wherein each of said sub-arrays has its own read out channel to allow parallel and simultaneous readout of all sub-arrays of the array. 32. The system of claim 22, wherein said filter further comprises a covering window for said array. 33. The system of claim 22, wherein said filter defines N separate filter bands and wherein said array further comprises N sub-arrays, and wherein N is an integer greater than or equal to 4. 34. The system of claim 29, wherein said array is sensitive to infra-red radiation and generates multi-spectral or hyperspectral imagery in the infra-red band. 35. The system of claim 22, wherein said array comprises a Mercury Cadmium Telluride focal plane array. 36. The system of claim 22, wherein each of said sub-arrays has its own read out channel to allow parallel and simultaneous readout of all sub-arrays of the array. 37. The system of claim 22, wherein each of said sub-arrays has separate and variable clocking of pixels in the column direction depending on the spectral responsiveness of the material forming said sub-array. 38. The system of claim 22, wherein said array comprises a photosensitive material constructed from Indium Antimonide. 39. A method of obtaining images of a scene of interest in multiple portions of the electromagnetic spectrum with a hyperspectral or multi-spectral imaging system aboard a reconnaissance vehicle, comprising the steps of:exposing a two-dimensional electro-optical array to said scene, said array arranged as a plurality of rows and columns of individual pixel elements, said array organized into a plurality of sub-arrays of rows of said pixels,controlling the wavelength of the radiation impinging on each of said sub-arrays wherein each sub-array images a different band of the electromagnetic spectrum while said array is exposed, wherein said sub-arrays are exposed to said scene of interest at the same time, with each of said sub-arrays imaging a different portion of said scene of interest simultaneously in a particular band of the spectrum;operating a scanning device for said array so as to scan across said scene of interest while said array is exposed to said scene to thereby direct adjacent portions of said scene of interest onto said imaging array; andwhile said imaging array is exposed to said scene, clocking individual pixel elements of said array in a direction and at a rate to thereby increase the signal to noise ratio of the collected signal. 40. The method of claim 39, wherein said step of clocking further comprises providing time delay and integrate (TDI) circuitry clocking said individual pixel elements in each of said arrays in a column direction. 41. The method of claim 39, wherein said step of clocking comprises the step of transferring pixel information in both row and column directions to thereby 1) increase the signal to noise ratio of said array and 2) to compensate for relative motion of said reconnaissance vehicle with respect to said scene of interest. 42. The method of claim 39, wherein said step of clocking further comprises the step of varying the clocking of said sub-arrays depending on the spectral response of the material forming said sub-arrays. 43. The method of claim 39, wherein the clocking of said sub-arrays changes dynamically depending on the spectral content of incident radiation. 44. The method of claim 39, wherein the number of pixels in said sub-arrays varies in the column direction depending on the spectral response of the material forming said sub-arrays. 45. The method of wherein said array comprises a wafer scale, two-dimensional charge-coupled device. 46. The method of claim 39, wherein each of said sub-arrays is separated from an adjacent sub-array by an output transfer register. 47. The method of claim 46, wherein said output transfer register extends across the entire width of said array, wherein said array comprises a plurality of sub-arrays each extending in the row direction and across the entire width of said array, and wherein during an exposure of said array each sub-array simultaneously images a different portion of the scene of interest and the spectral content of the entire scene of interest is c aptured by scanning said scene of interest across all of said sub-arrays. 48. The method of claim 39, wherein said array comprises a hybrid array incorporating a CMOS readout structure. 49. The method of claim 39, wherein said array comprises a CMOS detector. 50. Imaging apparatus for use in a system obtaining hyperspectral or multi-spectral images, comprising, in combination:an electro-optical imaging array arranged as a plurality of rows and columns of individual pixel elements, said array organized into a plurality of sub-arrays of rows of said pixels, each sub-array being responsive to incident radiation from a scene of interest; anda multi-spectral or hyper-spectral filter placed in registry with said electro-optical imaging array, said filter defining a plurality of individual filter bands arranged in optical registry with said sub-arrays whereby each of said sub-arrays receives radiation passing through one of said individual filter bands,wherein each of said sub-arrays has separate and variable clocking of pixels in the column direction depending on the spectral responsiveness of the material forming said sub-array. 51. Imaging apparatus for use in a system obtaining hyperspectral or multi-spectral images, comprising, in combination:an electro-optical imaging array arranged as a plurality of rows and columns of individual pixel elements, said array organized into a plurality of sub-arrays of rows of said pixels, each sub-array being responsive to incident radiation from a scene of interest; anda multi-spectral or hyper-spectral filter placed in registry with said electro-optical imaging array, said filter defining a plurality of individual filter bands arranged in optical registry with said sub-arrays whereby each of said sub-arrays receives radiation passing through one of said individual filter bands;wherein each sub-array has a predetermined number of rows depending on the spectral responsiveness of the material forming said sub-array. 52. Imaging apparatus for use in a system obtaining hyperspectral or multi-spectral images, comprising, in combination:an electro-optical imaging array arranged as a plurality of rows and columns of individual pixel elements, said array organized into a plurality of sub-arrays of rows of said pixels, each sub-array being responsive to incident radiation from a scene of interest; anda multi-spectral or hyper-spectral filter placed in registry with said electro-optical imaging array, said filter defining a plurality of individual filter bands arranged in optical registry with said sub-arrays whereby each of said sub-arrays receives radiation passing through one of said individual filter bandswherein each of said sub-arrays is separated from an adjacent sub-array by an output transfer register; andwherein said output transfer register extends across the entire width of said array, wherein said array comprises a plurality of sub-arrays each extending in the row direction and across the entire width of said array, and wherein during an exposure of said array each sub-array simultaneously images a different portion of the scene of interest and the spectral content of the entire scene of interest is captured by scanning said scene of interest across all of said sub-arrays with a scanning device.