16 December 2013 Toward real-time spectral imaging for chemical detection with a digital micromirror device-based programmable spectral filter
Author Affiliations +
J. of Micro/Nanolithography, MEMS, and MOEMS, 13(1), 011111 (2013). doi:10.1117/1.JMM.13.1.011111
Hyperspectral imaging sensors have proven to be powerful tools for highly selective and sensitive chemical detection applications, but they have significant operational drawbacks including slow line-scanning acquisition, large data volume of the resulting images, and a detection time lag due to the computational overhead of the matched-filter analysis. We have recently developed and demonstrated a high-speed, high-resolution, programmable spectral filter based on the Texas Instruments DLP® digital micromirror device (DMD) that is capable of performing matched-filter image processing across a two-dimensional (2-D) field-of-view directly in the optical hardware and will enable real-time chemical detection without slow scanning, large data volumes or expensive postprocessing requirements. Based on traditional optical techniques, our spectral filter encodes the spectral information orthogonal to the spatial image information, enabling the DMD to encode matched-filter information into the spectral content of the scene without disturbing the underlying 2-D image. With this new technology, everything from simple multiband filters to very complicated hyperspectral matched filters can be implemented directly in the optical train of the sensor, producing an image highlighting a target signature within a spectrally cluttered scene in real time without further processing. We will first describe the implementation of a DMD as a multiplexing spectral selector for a 2-D field-of-view, discuss its utility as a multiband spectral filter, and show how the DLP’s® duty cycle-based grayscale capability enables the direct measurement of the adaptive matched filter. We will also show examples of multispectral and hyperspectral matched-filter images recorded with our visible spectrum prototype.
© 2014 Society of Photo-Optical Instrumentation Engineers (SPIE)
David L. Graff, Steven P. Love, "Toward real-time spectral imaging for chemical detection with a digital micromirror device-based programmable spectral filter," Journal of Micro/Nanolithography, MEMS, and MOEMS 13(1), 011111 (16 December 2013). http://dx.doi.org/10.1117/1.JMM.13.1.011111

Optical filters

Digital micromirror devices


Chemical detection

Image filtering


Data acquisition

Back to Top