旋转扫描式成像光谱仪高光谱的几何变形矫正  

Geometric Distortion Correction for Hyperspectral Image Using a Rotating Scan Reflector

作　　者：柯刚扬[1] 安宁[1] 田扬超[1] 马智宏[2] 黄文江[2] 王秋平[1] 

机构地区：[1]中国科学技术大学国家同步辐射实验室,安徽合肥230029 [2]北京市农林科学院,国家农业信息化工程技术研究中心,北京100097

出　　处：《光谱学与光谱分析》2012年第8期2223-2227,共5页Spectroscopy and Spectral Analysis

基　　金：国家(863计划)项目(2007AA10Z202,2010AA10Z201)资助

摘　　要：Offner成像光谱仪是一种线推扫式成像系统,需要光谱仪与物体之间存在相对移动,从而记录整个区域的光谱和形貌信息。在光谱仪镜头前放置一块反射镜进行旋转扫描,也可以对大尺度物体进行高光谱成像,并且相机固定不动。然而旋转扫描时,记录的高光谱图存在较大的几何误差。该工作分析一般情况下Offner成像光谱仪单次拍摄得到的物点和像点的投影关系;根据投影关系,以旋转角为变量,分析物点在成像面上的投影分布,给出图像几何变形的矫正方法。在成像光谱仪上设计并安装了反射镜旋转扫描装置,进行旋转扫描实验,通过矫正算法,得到了清晰的高光谱图。Offner imaging spectrometer is a kind of pushbroom imaging system. Hyperspectral images acquired by Offner ima- ging spectrometers require relative motion of sensor and scene that is translation or rotation. Via rotating scan with a reflector at the front of sensor＇s len, large objects can be entirely captured. But for the changes in object distances, geometric distortion oc- curs. A formula of space projection from an object point to an image point by one capture was derived. According to the projec- tion relation and slit＇s motion curve, the object points＇ coordinates on a reference plan were obtained with rotation angle for a variable. A rotating scan device using a reflector was designed and installed on an Ofiner imaging spectrometer. Clear images were achieved from the processing of correction algorithm.

关 键 词：OFFNER 成像光谱仪 旋转扫描 线扫描 

分 类 号：TH744[机械工程—光学工程]