The Hadamard transform spectral imager based on a digital micro-mirror device (DMD) is a novel type of spectral imager developed in recent years. This paper describes the designing scheme of the Hadamard encoding mask and analyzes the encoding process of the detector pixels. Generally the Hadamard encoding mask constructed by DMD cannot completely encode the dispersed spectrum of all the pixels according to the Hadamard matrix; therefore, the spectral images recovered by inverse Hadamard transform inevitably have errors. A correction method for the recovered spectral images is proposed. The experimental results show that this method improves the quality of the recovered spectral images.
Jun Xu, Bingliang Hu, and Dazheng Feng, "The Correction of Recovered Spectral Images in a Hadamard Transform Spectral Imager Based on a Digital Micro-Mirror Device," Appl. Spectrosc. 66, 1044-1052 (2012)