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Capacitive Interdigital Sensor with Inhomogeneous Nematic Liquid Crystal Film

By Alaeddin Abu-Abed and Robert Lindquist
Progress In Electromagnetics Research B, Vol. 7, 75-87, 2008


The performance of capacitive interdigital sensors involved with anisotropic and inhomogeneous nematic liquid crystal (LC) film is investigated. These sensors have potential applications in chemical and biological systems. The theory for modeling the permittivity tensor of the LC film as a function of the molecular orientation is presented. The LC film is handled as inhomogeneous material where molecules are assumed to have different orientations with respect to the frame axes. Under these conditions, fringing field capacitances as functions of the molecular deformations are calculated. Examples of modeled capacitive interdigital sensors in the present of different inhomogeneous distributions of LC films will be studied and discussed.


Alaeddin Abu-Abed and Robert Lindquist, "Capacitive Interdigital Sensor with Inhomogeneous Nematic Liquid Crystal Film," Progress In Electromagnetics Research B, Vol. 7, 75-87, 2008.


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