光子学报, 2013, 42 (8): 902, 网络出版: 2013-09-25
新型阿达玛变换光谱仪
A New Kind of Hadamard Transform Spectrometer
近红外光谱仪 阿达玛变换 柱面镜 光谱带宽 Nearinfrared spectrometer Hadamard transform Cylindrical lens Spectral bandwidth
摘要
为了克服经典光谱仪中由于入射狭缝的遮挡导致的系统内光通量很小的缺点,提出了一种新型阿达玛变换光谱仪的设计理念. 给出了以柱面镜来整形光束的方法,利用理论计算得出含有数字微镜阵列光谱仪的光谱分辨能力和像元分辨能力,确定了该类光谱仪的极限分辨率.根据几何光学成像理论,提出一种增大成像透镜焦距的优化方案,可以提高光谱分辨率,并且更有益于机械装调. 实验结果表明,该阿达玛变换光谱仪具有高光通量、提高5倍的信噪比、较小的光谱带宽(3.5 nm)等特点,可为微弱光谱信号的检测提供便利条件;光谱仪选择的近红外探测器无需制冷,降低了阿达玛变换光谱仪的制作成本,具有更强的市场竞争力.
Abstract
In order to overcome the shortcoming that the luminous flux of the classical spectrometer is small due to the occlusion of the entrance slit, a design concept of the new kind of Hadamard transform spectrometer is proposed. A method of shaping the beam by a cylindrical lens is given. Using theoretical calculations of the spectral resolution ability and the pixel resolution ability of the spectrometer, containing a digital micromirror array, he limit class of the spectrometer resolution can be determined. Based on the geometric theory of optical imaging, an optimization program of the more focal length of the imaging lens is proposed, which is able to obtain the higher spectral resolution and the more beneficial to the mechanical alignment. The advantages of the new Hadamard transform spectrometer are that it has a high luminous flux, the signaltonoise ratio is 5 times more than that of traditions, and the smaller spectral bandwidth is 3.5 nm, providing convenient conditions for the detection of weak spectral signal. In addition, the nearinfrared detector selected by the spectrometer needs no refrigeration, which will cut the production costs of the Hadamard transform spectrometer, with a stronger market competitiveness.
党博石, 刘华, 王晓朵, 许家林, 卢振武. 新型阿达玛变换光谱仪[J]. 光子学报, 2013, 42(8): 902. DANG Boshi, LIU Hua, WANG Xiaoduo, XU Jialin, LU Zhenwu. A New Kind of Hadamard Transform Spectrometer[J]. ACTA PHOTONICA SINICA, 2013, 42(8): 902.