Measurement of Effective Refractive Index of Nematic Liquid Crystal in Fabry-Perot Etalon

다국어 초록 (Multilingual Abstract)

We report a measurement of the effective refractive index of a nematic liquid crystal (NLC) insidea Fabry-Perot (FP) etalon according to the applied electric fields. The effective refractive index of theNLC depends on the intensity of the applied electric field. A wavelength-swept laser with apolygon-scanner-based wavelength filter is used as a wide-band optical source to measure the effectiverefractive index of the NLC. The bandwidth of the optical source is greater than 90 nm around 1300nm. The fabricated NLC FP etalon consists of glass substrates, gold layers as the electrodes with highlyreflective surfaces, polyimide layers as the planar alignment layers, and an LC layer. Furthermore, wemeasured the Freedericksz transition voltages for three types of NLC FP etalons having thicknesses of30.6 μm, 55.4 μm, and 108.8 μm. The Freedericksz transition voltages in the three cases are nearly equal.
The measured effective refractive indices in the three cases decreased from 1.67 to 1.51 as the appliedelectric field intensity was increased. Beyond the threshold electric field, the effective refractive indicesquickly decreased and eventually saturated at a value of 1.51 for all cases

참고문헌 (Reference)

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