Acousto-optic-tunable-filter-based spectropolarimetric imagers for medical diagnostic applications—instrument design point of view

Neelam Gupta
2005 Journal of Biomedical Optics  
Compact optical imagers that can detect both spectral and polarization signatures are required in many biomedical applications. An acousto-optic-tunable-filter ͑AOTF͒-based imager is ideally suited to provide both agile spectral and polarization signatures. Such an imager can be readily used for real-time in vivo medical diagnostic applications. We develop a family of small, robust, and programmable hyperspectral imagers operating from the ultraviolet ͑UV͒ to the long-wave IR ͑LWIR͒. Such
more » ... s require minimal data processing because they can acquire images at only select wavelengths of interest. We use AOTFs made of KDP, TeO 2 , and TAS with Si-based CCD, InGaAs, InSb, and HgCdTe cameras to cover different spectral regions from the UV to the LWIR. Operation of each of these imagers and image acquisition is computer controlled. The most developed imager covers the visible to near-infrared ͑VNIR͒ region from 400 to 900 nm, with a 10-nm spectral resolution at 600 nm, it uses an electronically tunable TeO 2 AOTF as a bandpass filter, and a nematic liquid crystal retarder to change polarization. We describe our concept in the development of these imagers and present new results obtained using the VNIR imager. © 2005 Society of Photo-Optical Instrumentation Engineers.
doi:10.1117/1.2102507 pmid:16292960 fatcat:jgicd5ffanck5h3zdvfyybc2um