计算光谱成像技术利用计算方法改变传统成像方式, 在光路中引入编码模板实现正变换, 最后通过逆变换获得目标光谱数据立方体。 介绍了一种推扫式编码孔径计算光谱成像仪的成像原理, 在实际应用中, 其推扫速度与帧频的匹配误差会影响光谱数据重构的准确性。 在建立了推扫模型的基础上, 得到了重构数据的误差项, 分析了匹配误差对光谱数据重构的影响, 并引入光谱二次导数误差和strehl比分别作为复原光谱和空间图像的评价参数, 进行了数据仿真分析, 结果表明, 当一组完整数据的累积误差超过一个像元时, 明暗变化剧烈的区域恢复结果比较差, 而对比较均匀的区域影响不大; 累计误差不超过0.5个像元时, 各通道的strehl比均在0.9以上, 并且光谱能量越低的通道strehl比越小, 因此编码模板的行列数越多平台的稳定性要求越高。

The technology of computational spectral imaging changes the traditional imaging modalities by introducing a coded aperture in the optical path to achieve transformation of the targets spectral imformation, then we can get the spectral data cube by reverse transform. This paper introduces the principle of a push-broom imaging coded aperture computational spectral imager. In practical applications, the matching error between the push speed and the frame rate can affect the accuracy of the spectral data reconstruction. The error terms are deduced based on the model of pushroom, the influences of matching errors to the spectral data reconstruction are anlyzed. And the second spectra derivative and strehl ratio are introduced as the evaluation parameters to, respectively, evaluate the reconstructed spectral and spatial image in the data simulation analysis. It showed that, when the accumulated error of a complete set of data is more than one pixel, the shading dramaticly area’s reconstructed results are relatively poor, but the relatively homogeneous regions are affected small; when cumulative error does not exceed half pixel, strehlretio of each channel were above 0.9, and the lower of the spectral energy, the channels strehl ratio smaller, so the more the ranks of the coding template, the higher the platform’s stability required.