Capacitive Transduction for Liquid Crystal-Based Sensors, Part I: Ordered System

Author

Abu-Abed, Alaeddin ; Lindquist, Robert G. ; Choi, Woo-Hyuck

Author_Institution

Univ. of Alabama at Huntsville, Huntsville

Volume

7

Issue

12

fYear

2007

Firstpage

1617

Lastpage

1624

Abstract

In this paper, the theory for tracking the average molecular orientation of a liquid crystal (LC) material via capacitive sensing of anisotropic media is presented. The candidate LC sensor structure utilizes interdigital electrodes. Two capacitive measurements in orthogonal direction can track the director axis of nematic LC material in a homogenous ordered LC film. The sensitivity for the sensor at different alignments is studied. The candidate sensors have been fabricated and experimentally verified. Both experimental and calculated values for capacitances of selected interdigital fingers sensor structures are presented.

Keywords

anisotropic media; capacitive sensors; interdigital transducers; liquid crystal devices; molecular orientation; nematic liquid crystals; anisotropic media; capacitive measurement; capacitive transduction; interdigital electrode; liquid crystal-based sensor; sensor fabrication; tracking; Anisotropic magnetoresistance; Biological materials; Biosensors; Capacitive sensors; Chemical and biological sensors; Chemical sensors; Crystalline materials; Liquid crystals; Optical distortion; Sensor systems; Biosensors; capacitive sensing; chemical sensors; liquid crystal (LC);

fLanguage

English

Journal_Title

Sensors Journal, IEEE

Publisher

ieee

ISSN

1530-437X

Type

jour

DOI

10.1109/JSEN.2007.908504

Filename

4373292