Developing an optimum computer-designed multispectral system comprising a monochrome CCD camera and a liquid-crystal tunable filter.

In a previous work [J. Opt. Soc. Am. A24, 942 (2007)JOAOD60740-323210.1364/JOSAA.24.000942] we made a complete theoretical and computational study of the influence of several parameters on the behavior of a planned multispectral system for imaging skylight, including the number of sensors and the spectral estimation algorithm. Here we follow up this study by using all the information obtained in the computational simulations to implement a real multispectral imaging system based on a monochrome CCD camera and a liquid-crystal tunable filter (LCTF). We were able to construct the optimum Gaussian sensors found in the simulations by adjusting the exposure times of some of the transmittance modes of the LCTF, hence obtaining really accurate spectral estimations of skylight with only a few optimum sensors.