Compressive-Scan Camera: 1-Channel IR Detector Analog Front End

In cooperation with InView Technology. Compressive scanning is a scheme for doing image sensing with a single-element detector, without suffering the N2 speed penalty of raster scanning. It's a sort of combination of scanning and image compression—you use a digital micromirror device (DMD) to multiply the image by a series of 1-bit digital basis functions, measure the resulting photocurrent, and then invert the transform to produce a compressed image. That's not too useful in the visible, where image sensors are cheap commodity items, but in the UV and especially the shortwave IR (SWIR), image arrays are extremely expensive, so there's a need for compressive scan cameras.


This front end had to reach the shot noise limit with high-capacitance SWIR photodiodes at very low photocurrents, which is a difficult combination.