光学学报, 2020, 40 (2): 0230001, 网络出版: 2020-01-02
微小型快照式傅里叶变换成像光谱仪的建模与分析 下载: 1243次
Modeling and Analysis of Miniature Snapshot Fourier-Transform Imaging Spectrometer
摘要
为了实时探测运动场景、迅变目标的图像与光谱,提出了一种微小型快照式傅里叶变换成像光谱仪,利用多级微反射镜对微透镜阵列形成的多重像场进行分布式相位调制,实现了干涉图谱信息的实时获取。根据微透镜阵列与多级微反射镜对光场的相位调制特性,建立了多重干涉成像的理论模型,计算表明,不同视场的干涉像点位于探测平面的不同区域,但大视场情况下相邻通道之间的干涉图像单元会发生串扰,并导致复原光谱失真。分析表明,为了抑制相邻干涉成像通道间发生串扰,视场角应控制在微透镜阵列和多级微反射镜的衍射与离焦效应所限定的极限视场角之内。同时,视场角还会引入相位误差,并导致归一化光谱误差随视场角的增大而单调递增。根据归一化光谱误差关系曲面可以对系统的视场角进行合理的设计,从而实现对目标场景中特定区域的有效探测。
Abstract
A miniature snapshot Fourier-transform imaging spectrometer is proposed to realize the real-time detection of images and spectra of moving scenes and fast-changing targets. Interferometric imaging spectra are acquired in real time using two multi-stage micro-mirrors to modulate the distributed phase of multiple image fields formed by a micro-lens array. Based on phase modulation by the micro-lens array and multi-stage micro-mirrors on the optical field, a theoretical model is established for multiple interferometric imaging. Numerical results show that the interferometric image points with different field of view (FOV) are located at different areas on the detector plane. However, in the case of a large FOV, the interferometric image units between adjacent channels have crosstalk and the recovered spectrum is distorted. To suppress the crosstalk between adjacent channels, the FOV angle can be controlled within the limited FOV determined by the diffraction and defocusing effects of the micro-lens array and multi-stage micro-mirrors. Simultaneously, the FOV introduces phase errors, which causes monotonously increasing normalized spectral errors according to the FOV angle. Based on the normalized spectral error analysis results, the FOV can be rationally designed to achieve effective detection of a specific area in target scenes.
吕金光, 梁静秋, 王维彪, 秦余欣. 微小型快照式傅里叶变换成像光谱仪的建模与分析[J]. 光学学报, 2020, 40(2): 0230001. Jinguang Lü, Jingqiu Liang, Weibiao Wang, Yuxin Qin. Modeling and Analysis of Miniature Snapshot Fourier-Transform Imaging Spectrometer[J]. Acta Optica Sinica, 2020, 40(2): 0230001.