层析型线阵推扫成象光谱技术及其仿真研究

COMPUTED-TOMOGRAPHIC PUSHBROOM IMAGING SPECTROMETER WITH A LINEAR CCD AND ITS SIMULATED EXPER IMENT

本文设计了一种层析型线阵推扫成象光谱仪． 与色散型推扫成象光谱仪或干涉型推扫成象光谱仪不同的是，它用线阵ＣＣＤ 代替面阵ＣＣＤ，同时又具有高通量、多通道、高信噪比、结构简单、轻量等优点． 其基本原理是利用光栅的多级衍射实现视场条带目标的一维空间和一维光谱组成的“空间－光谱平面”到一维投影象的Ｒａｄｏｎ 变换，然后由逆Ｒａｄｏｎ 变换重构二维数据（一维光谱和一维空间），另一维空间信息通过推扫便可得到． 文章还提供了重构算法和计算机仿真试验结果，验证了算法和方案的可行性．

A new pushbroom chromotomographic imager with a linear CCD is produced in this paper.This spectral imager possesses of high throughput,multi spectral,high signal to noise,simplicity.It employs a linear CCD other than an area CCD employed by other pushbroom spectral imager.A phase grating being employed,the spectral imager realizes the Radon transform of the spatial spectral plane of the strip target and captures several projections of different diffraction angles (which are also the projection angles of the Radon transform) during one exposure.Therefore,the spatial spectral plane of the strip can be reconstructed from the projections.It is chosen a truncated singlar value decomposition as the reconstruction algorithm.The simulated experiments are made,and it is got the spectral image of the strip consisting of 59 spatial pixels and 10 spectral when a 1024 linear CCD is chosen.The simulation results show that the theorem is right,and that the reconstruction algorithm is robust and reliable.