Broadband Wide Field of View Imaging with Computational Mirrors
This work addresses the long-standing challenge of broadband achromatic imaging for wide-field-of-view systems, offering a practical computational alternative to complex refractive optics for applications like remote sensing and surveillance.
Computational Mirrors enable high-resolution, wide-field-of-view imaging across the full VIS-SWIR spectrum (400-1700nm) using a single sensor by capturing a minimal focal stack (2-4 images) and applying a physics-inspired spatially-varying PSF model (SeidelConv). The approach achieves sharp images across all wavelengths without refocusing, demonstrated with a 50mm F/1 and 100mm F/2 system.
Traditional glass-based optics are typically optimized for narrow spectral bands, such as the visible (400-700nm) or shortwave infrared (1000-1800nm). While the emergence of VIS-SWIR sensors (400-1700nm) offers transformative potential, refractive optics struggle to focus this entire range simultaneously. Mirrors represent a promising achromatic alternative; however, they are often sidelined by field curvature, and off-axis aberrations. This paper introduces Computational Mirrors, a framework that enables high-resolution, wide-field-of-view imaging across the complete VIS-SWIR spectrum using a single sensor. Our method is built on the observation that distinct regions of the field of view reach focus at varying distances from the mirror. By capturing a minimal focal stack (2-4 images), we utilize a computational backend to recover a sharp, all-in-focus image. A key contribution of this work is SeidelConv, a novel, physics-inspired, spatially-varying point spread function (PSF) model designed to accurately characterize and correct the off-axis aberrations inherent in simple concave mirrors. We demonstrate the efficacy of our approach using a first-of-its-kind 50mm F/1 optical system equipped with a VIS-SWIR sensor. Our system produces sharp images across RGB, NIR, and SWIR wavelengths without requiring refocusing, revealing material details invisible within individual spectral bands. We further validate the scalability of our approach with a 100mm F/2 system optimized for long-range imaging.