Hyperspectral imaging (HSI) is a technique with a growing list of applications and potential users, as this technique combines the power of imaging with the chemical discrimination of spectroscopy. Because HSI divides light from the scene into narrow slices of wavelength, the technique is typically thought to require cryogenic arrays to achieve the ultimate sensitivity. However, within the last two decades microbolometer arrays have improved in sensitivity, pixel count and total array area. In Hawai’i we have shown that microbolometer arrays can provide sufficient sensitivities for a variety of infrared HSI applications. The ability of microbolometer arrays to operate at ambient-temperature make them attractive candidates for low power applications, including space-based instruments on small satellites. We have two NASA projects to determine the suitability of uncooled microbolometers for HSI systems with the aim of HSI measurements from smaller satellites than is possible with cryogenic instruments. The suitability of a detector is governed in part by its spectral response. Microbolometers have wide variations in spectral response by technology and vendor, as part of our NASA projects we are conducting a spectral response measurement campaign on five different microbolometer cameras. Three of the cameras are sensitive to the long-wave infrared from 7.5 to 14 microns (two FLIR cameras and a Sofradir camera), one to the mid-wave infrared from 3 to 5 microns (LumaSense camera), and the last is sensitive to both regions from 3 to 14 microns (INO camera). Results from this campaign will be presented.
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