Optical design and development of an underwater dual-channel microlens array integral field snapshot hyperspectral imager

Abstract

Compared to push-scan hyperspectral imagers, snapshot hyperspectral imagers offer an advantage by minimizing sensitivity to attitude jitter in underwater mobile platforms. Here we present the optical design and development of an underwater microlens array integral field hyperspectral imager. The system comprises a panchromatic imaging channel with a high spatial resolution and a spectral imaging channel with a lower spatial resolution. Through the fusion of high-resolution panchromatic images and low-resolution spectral images, we achieve high spatial resolution hyperspectral images. Both the panchromatic imaging channel and the spectral imaging channel share a common front objective, featuring a 25 mm focal length and a wide 36° field of view angle. Utilizing prism dispersion, the spectral imaging system spans a band range from 465 to 700 nm with a spectral resolution of less than 10 nm. Specialized algorithms for spectral image reconstruction and image fusion have been developed. The experimental results across diverse scenes confirm the exemplary spectral imaging performance of the system, positioning it as a robust solution for underwater snapshot hyperspectral imaging.