Title :
A High-Speed Measurement Method for Reflective Liquid Crystal Cells Using a Liquid Crystal Polarization-Converting Device
Author :
Kawamura, Marenori ; Sato, Susumu
Author_Institution :
Dept. of Electron. Eng., Akita Univ.
fDate :
3/1/2007 12:00:00 AM
Abstract :
We propose a novel measurement method for determining cell parameters, such as a cell thickness and twist angle in reflective liquid crystal (LC) cells, by using a unique polarization-converting device prepared with a circularly and homogeneously aligned LC (CH-LC) cell. The light intensity distributions from the reflective LC cell transmitted twice through the CH-LC cell are measured by a charge-coupled device array camera. Cell thickness can be derived by using coordinate values of local minimum spot in the spatial light intensity distribution measured at one wavelength, where the pretilt angle is assumed to be the designed value. Both cell thickness and twist angle can also be determined by two local minimum positions of the light intensity at two different wavelengths and the effects of a quarter-wave plate are discussed
Keywords :
angular measurement; light polarisation; liquid crystal displays; thickness measurement; cell parameters; cell thickness; charge-coupled device array camera; high-speed measurement; liquid crystal polarization-converting device; quarter-wave plate; reflective liquid crystal cells; twist angle; Charge coupled devices; High speed optical techniques; Liquid crystal devices; Liquid crystal displays; Optical arrays; Optical polarization; Optical retarders; Optical surface waves; Thickness measurement; Wavelength measurement; Cell thickness; high-speed measurement; liquid crystal (LC) polarization-converting device; reflective LC cells; twist angle;
Journal_Title :
Display Technology, Journal of
DOI :
10.1109/JDT.2006.888916
