Parallel evaluation for detector devices of the hyperspectral imager with a supercontinuum source

摘要

In order to guarantee the observed data with high spatial and wavelength resolution of hyperspectral/multispectral imagers, it is necessary to evaluate the difference of the spectral sensitivity among the detector devices arrayed two-dimensionally and correct spectral and spatial misregistrations and the effect of stray light. However, there are tens of thousands of detectors in hyperspectral imagers, so they have to be evaluated in parallel by the special technique. Therefore, a light-source system which has high radiance with the spatial uniformity and widely tunable wavelength-range is required instead of the conventional lamp system. In this presentation, we report the new setup of the supercontinuurn(SC)-source-monochromator system and its fundamental performance. The SC source covers a wavelength range of 450-2400 nm, and its total output power is up to 6 W. We effectively coupled a high-power SC laser to a single monochromator and obtained spatial uniformity through an integrating sphere or a relay-optics system. The radiance three or more magnitudes higher than a tungsten halogen lamp was measured with the supercontinuum-source based system. The stability of output power and the spatial uniformity of radiance at the integrating-sphere port were also evaluated. Using the system, spectral misregistrations and responsivities of a hyperspectral imager, which is consist of a polychromator and two-dimensional array of CCD, were measured.