Optical Engineering • Open AccessDevelopment of a fast chromotomographic spectrometer
A method for preprocessing spectral information produced by chromotomographic imagers combined with a new postprocessing strategy is proposed. The new technique makes it possible to collect both spectral and limited spatial information from a chromotomographic sensor at kilohertz rates with a conventional charge-coupled device (CCD) array. The proposed technique involves forming a vector projection of each 2-D frame collected by the sensor. The vector projections are postprocessed via a reconstruction algorithm that produces 1-D profiles of the scene and a spectrum for each 1-D pixel. This on-chip preprocessing approach results in a large reduction of the bandwidth through the analog to digital converter, while maintaining the desired temporal resolution of the sensor. High-speed CMOS cameras can obtain comparable speeds, but at significant added cost in hardware and postprocessing time. This makes the proposed sensor attractive for applications where large numbers of sensors are required and the need to obtain spectral information quickly is of paramount importance.