Optimization Method for Broadband Filter Set with Equal Light Efficiency in Spectral Imaging Systems

Abstract

Optimal broadband filter set can provide better performance than narrowband filter set in spectral imaging systems. However, previous studies have not considered the impact of differences in the light efficiency of broadband filters. To address this problem, an optimization method for broadband filter set with equal light efficiency (BFSELE) is proposed and verified in this paper. The cost function of the optimal broadband filter set is constructed based on the principle of minimizing the condition number. An optimal BFSELE is obtained by introducing the constraint of equal light efficiency. A systematic comparison in terms of color reproduction and spectral reconstruction is conducted between two broadband filter sets, one with equal light efficiency and another without it. The simulation results show that the optimal BFSELE can provide better performance, which validates the feasibility of the method. Meanwhile, the broadband filter set with a light efficiency of around 50% demonstrated the best results than others broadband filter sets. The proposed optimization method for BFSELE offers a new approach to achieving high-quality and real-time spectral acquisition.

Keywords: spectral imaging, spectral reconstruction, spectral sensitivity optimization, broadband filter, equal light efficiency, condition number