A compact, high-speed, and low-cost hyperspectral imager

Abstract

Although the potential of hyperspectral imaging has been demonstrated for several applications, using laboratory setups in research environments, its adoption by industry has so far been limited due to the lack of high speed, low cost and compact hyperspectral cameras. To bridge the gap between research and industry, we present a novel hyperspectral sensor that integrates a wedge filter on top of a standard CMOS sensor. To enable the low-cost processing of a microscopic wedge filter, we have introduced a design that is able to compensate for process variability. The result is a compact and fast hyperspectral camera made with low-cost CMOS process technology. The current prototype camera acquires 100 spectral bands over a spectral range from 560 nm to 1000 nm, with a spectral resolution better than 10 nm and a spatial resolution of 2048 pixels per line. The speed is 180 frames per second at illumination levels as typically used in machine vision. The prototype is a hyperspectral line scanner that acquires 16 lines per spectral band in parallel on a 4 MPixel sensor. The theoretic line rate for this implementation is thus 2880 lines per second.