基于内拼接法的宽视场成像光谱仪研制

Development of wide field-of-view imaging spectrometer using inner-stitching

为了增大成像光谱仪的视场,提高遥感成像的作业效率,开展了内拼接宽视场成像光谱仪的设计和研制。针对推扫成像方式,分析了基于内拼接法的宽视场成像光谱仪的组成。利用两台Offner凸面光栅分光系统进行拼接,研制了原理样机。在实验室中对原理样机的像元对准误差、光谱分辨率和调制传递函数进行测试并进行了室外成像实验。测试结果表明原理样机光谱维像元对准误差约为0.15个像元(波长为479nm),交轨方向和顺轨方向空间维像元对准误差分别为0.16个像元和0.19个像元。原理样机的光谱分辨率约为1.6nm,Nyquist频率处的调制传递函数值约为0.2。通过原理样机的研制和实验验证了内拼接法增加成像光谱仪视场的有效性。

In order to increase the field of view（FOV）of imaging spectrometer and improve the efficiency of the remote sensing,a wide FOV imaging spectrometer using inner-stitching was designed and developed.First,the constitution of the pushbroom imaging spectrometer using inner-stitching was analyzed.Then two Offner-type dispersion systems using convex grating were stitched and a prototype of the imaging spectrometer based on inner-stitching was developed.The pixel misalignment,the spectral resolution and the modulation transfer function（MTF）of the prototype were measured in the laboratory.Finally,the outdoor spectral imaging experiment was accomplished.The measurements show that the pixel misalignment in spectral dimension is about 0.15pixel（the wavelength is 479nm）and the misalignment in spatial dimension is about 0.16 pixel and 0.19 pixel for cross-track and along-track direction respectively.The spectral resolution of the prototype is about 1.6nm and its MTF value atNyquist frequency is about 0.2.The development and the experiment validate the effectiveness of using inner-stitching to increase the FOV for imaging spectrometer,and lay the foundation for the future work.