Spectrum Reconstruction of the Light-Field Multimodal Imager

The multimodal light-field imager can simultaneously capture spectral and polarization characteristic of a two-dimensional target. Due to the diffraction and misalignments of the imaging system, the pixels receive the light passing through different spectral filters and polarizing filters. As a result, the spectral and polarization images constructed by extracting the corresponding filter-pixels contain unwanted information from the other channels. In this paper, we present an imaging model of the spectral and polarimetric radiance for the multimodal light-field imager. Based on the radiance imaging model, calibration schemes are also proposed for determining the spectral response coefficients and polarization response coefficients of the imager. A data reconstruction method based on Tikhonov regularization is proposed to reconstruct the target spectrum with better accuracy. Calibrating and imaging experiments of a prototype are performed and the results confirm the effectiveness of the data reconstruction approach.