High spatial resolution hyperspectral camera based on exponentially variable filter

The architecture and calibration of a hyperspectral imaging sensor based on an exponentially continuously variable narrow-band transmission filter is described. The system design allows for great flexibility in choice of sensors and lenses to be used. Spectral and radiometric calibration using lenses of different focal length and vignetting characteristics is described. The point-spread-function at different wavelengths depends on the lens design and the f-number. The advantage of using a tilt/shift lens is demonstrated. Low f-number lenses show vignetting, which influences both the spectral and radiometric calibration. Retroeffects in the microlenses of the focal plane array are observed but to a large extent will be remedied by future improvements in the optical filter. Noise properties of the sensor system are discussed, and signal-to-noise ratios estimated. From the model, it is possible to obtain parametric performance variations based on the properties of key components. Finally, the sensor performance is indicated by demonstrating a spectral image. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License.