Research on the Interlaced Encoding Pixels in Hadamard Transform Spectral Imager Based on DMD
XU Jun1,2, HU Bing-liang1*, FENG Da-zheng3, ZHANG Wen1,2, YAN Peng1
1. Key Laboratory of Spectral Imaging Technique，Xi’an Institute of Optics and Precision Mechanics，Chinese Academy of Sciences，Xi’an 710119，China 2. Graduate University of Chinese Academy of Sciences，Beijing 100049，China 3. National Lab for Radar Signal Processing, Xidian University, Xi’an 710071, China
Abstract：The key innovation in Hadamard transform spectral imager (HTSI) introduced recently is the use of digital micro-mirror device (DMD) to encode spectral information. However, it brings some new problems for us to solve synchronously. An interlaced encoding phenomenon caused by the application of DMD to our HTSI was investigated and analyzed. These interlaced encoding pixels were not encoded based on Hadamard transform; therefore they should be processed specially in spectrum recovery. To improve the quality of the recovered spectral images, a positioning method and a decoding method for the interlaced encoding pixels were proposed. In our experiment, we first directed a beam of laser into our HTSI to fill the field of view and labeled the positions of the interlaced encoding pixels. Then we recorded two groups of the encoded images of the target by changing the positions of all the encoding channels on the DMD. The interlaced encoding pixels could be distinguished easily by observing the number of non-zero constants and zero elements in a column vector which is made up of the gray values of a pixel of the encoded images in sequence. The interlaced encoding pixels of the first group of the encoded images turned into the normal Hadamard encoding pixels of the second group of the encoded images. The interlaced encoding pixels of the first group of the encoded images can be decoded through applying inverse Hadamard transform to the corresponding pixels of the second group of the encoded images. The experimental results prove the feasibility of the decoding method.
徐 君1,2，胡炳樑1*，冯大政3，张 雯1,2，闫 鹏1 . 基于DMD的哈达玛变换成像光谱仪中交错编码像素点的研究[J]. 光谱学与光谱分析, 2012, 32(01): 278-282.
XU Jun1,2, HU Bing-liang1*, FENG Da-zheng3, ZHANG Wen1,2, YAN Peng1 . Research on the Interlaced Encoding Pixels in Hadamard Transform Spectral Imager Based on DMD. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2012, 32(01): 278-282.
[1] Harwit M, Sloane N J A. Hadamard Transform Optics, Academic, New York, 1979. [2] Marshall A C. Fourier, Hadamard and Hilbert Transforms in Chemistry. Plenum Press, New York, 1982. [3] Kenneth D Fourspring, Zoran Ninkov, John P Kerekes, et al. Proc. SPIE，2010，7739：77393X. [4] Wu Y, Chen C, Ye P，et al. Proc. SPIE，2009，7210：72100F. [5] Goldstein N, Vujkovic-Cvijin P, Fox M J, et al. Spectral Encoder, US Patent, 2008, 7: 324, 196. [6] Waldis S，et al. Proc. SPIE，2008，7018：70182S. [7] Chen Yuheng, Ji Yiqun, Zhou Jiankang, et al. Proc. SPIE，2010，7658：765834. [8] Michaem Canonica, Frederic Zamkotsian, Patrick Lanzoni, et al. Proc. SPIE，2011，7930：79300N. [9] DeVerse R A, Hammaker R M, Fateley W G, et al. J. Mol. Struct., 2000，521：77. [10] Spanò P，et al. Proc. SPIE，2009，7436：74360O. [11] Gehm M E，Kinast J. Proc. SPIE，2008，6978：69780I. [12] Fixsen D J, Greenhouse M A, MacKenty J W, et al. Proc. SPIE，2009，7249：72490X. [13] Wei Wei, Huang Shanglian, Zhu Yong, et al. Proc. SPIE，2008，7159：71590N. [14] Goldstein N, Vujkovic-Cvijin P, Fox M, et al. Proc. SPIE，2009，7210：721008. [15] Love S P. Proc. SPIE，2009，7210：721007. [16] Vujkovic-Cvijin P, Goldstein N, Fox M J, et al. Proc. SPIE，2006，6206：33.
