3c02 OTDR signal properties of a liquid crystal composite device with cholesteric liquid crystal filters

Abstract

We propose a liquid crystal (LC) composite device with two pairs of a twisted nematic (TN) LC cell sandwiched between two cholesteric (Ch) LC filters at same wavelength of the selective reflection. The transmission and reflected light intensities at two different near infrared wavelengths of 850 nm and 1300 nm can be changed selectively by applying the voltages to each nematic LC cell. The reflected signal level and the position of the plural LC composite devices attached at the end of optical fibers can be determined by using an optical time domain reflectometery (OTDR) system.