计算光谱成像是一种新型的光谱成像技术,具有高通量、快照式成像等优点,但关于其成像质量评价的研究还很少。工作中探索了一种计算光谱成像系统成像质量的定量评价方法。该方法利用ISO 12233靶标作为目标源,进行成像、图谱信息重构,并通过测量重构图的调制传递函数(MTF)作为计算光谱成像系统的成像质量评价标准。结果表明,对于单帧采样,随着混叠谱段数的增加,重构图MTF迅速下降,当混叠波段的数目达到9个时,重构图MTF与目标场景图像相比已下降50%。该研究有助于理解计算光谱成像技术的优缺点,合理安排混叠谱段的数量,以精确地复原目标信息。
As a novel imaging spectrometry, computational imaging spectrometry(CIS)has the advantages of high throughput, snapshot imaging etc. However, there is little research on imaging quality evaluation of CIS system. In the present paper, a quantitive evaluation method for imaging quality of CIS system was presented. ISO 12233 chart was used as the objective source, and then imaging and reconstruction of the spatial-spectral information was provided. Calculating modulation transfer functions (MTFs) for the reconstructed images was considered as the criterion of the imaging quality evaluation of CIS system. The result shows that MTFs for single-frame sampling decrease rapidly with the aliasing spectral number increasing. When the number of the aliasing spectra is 9, MTF for the reconstructed image decreases by 50% compared to the original scene. This work helps better understand the pros and cons of CIS system and arrange the aliasing spectral number reasonably to reconstruct the object scene precisely.