Characterizing the dynamic range of a hyperspectral camera

Abstract

The dynamic range of a hyperspectral camera can have a strong impact on the quality and integrity of the collected spectra. For the image sensor chip alone, the dynamic range is the ratio between the saturation level and the noise floor, set by full well capacity and readout noise respectively. In a complete hyperspectral camera, the raw signal level varies with the wavelength-dependent detector quantum efficiency, optics transmission, and illumination, as well as with the optical bandwidth. In practice, different parts of the spectrum will tend to have the highest or lowest signal level, and will most easily reach the saturation level or noise floor, respectively. It is shown that to define a dynamic range for a hyperspectral camera in the reflective spectral domain, the wavelength dependence of the camera light collection efficiency must be taken into account. A more application-oriented dynamic range can be defined by additionally assuming a shape of the illumination spectrum representative of a particular application.