Hyperspectral cameras face harsh trade-offs between spatial, spectral, and temporal resolution in inherently low-photon conditions. Computational imaging systems break through these trade-offs with compressive sensing, but have required complex optics and/or extensive compute. We present Spectrum from Defocus (SfD), a chromatic focal sweep method that achieves state-of-the-art hyperspectral imaging with only two off-the-shelf lenses, a grayscale sensor, and less than one second of reconstruction time. By capturing a chromatically-aberrated focal stack that preserves nearly all incident light, and reconstructing it with a fast physics-based iterative algorithm, SfD delivers sharp, accurate hyperspectral images. The combination of photon efficiency, optical simplicity, and physical interpretability makes SfD a promising solution for fast, compact, interpretable hyperspectral imaging.

翻译：高光谱相机在固有低光子条件下面临空间、光谱和时间分辨率之间的严峻权衡。计算成像系统通过压缩感知突破这些限制，但通常需要复杂的光学系统和/或大量计算。本文提出离焦光谱（SfD），一种色散焦面扫描方法，仅使用两个现成透镜、一个灰度传感器及不足一秒的重建时间即可实现先进的高光谱成像。通过采集保留几乎所有入射光的色差焦栈，并采用基于物理原理的快速迭代算法进行重建，SfD能够生成清晰准确的高光谱图像。其光子效率、光学简洁性与物理可解释性的结合，使SfD成为快速、紧凑、可解释高光谱成像的理想解决方案。