Optics: measuring and testing – By polarized light examination – With light attenuation
Patent
1998-05-05
2000-06-27
Font, Frank G.
Optics: measuring and testing
By polarized light examination
With light attenuation
356 36, 356 33, 356365, G01B 1124
Patent
active
060813377
ABSTRACT:
The present invention relates to methods and apparatus for measuring the optical properties, eg twist angle, cell gap, input director, of a transmissive or reflective liquid crystal cell. For a transmissive liquid crystal cell the cell is placed between a polarizer and an analyzer and the transmission spectrum observed while rotating the analyzer until zero transmission is obtained at at least one wavelength. The twist angle and the surface rubbing orientations of the liquid crystal cell are determined by the relative angle between the polarizer and the analyzer while the cell gap is determined from the calculated retardation value d.DELTA.n with known .DELTA.n. For reflective cells cell gap is determined based on a knowledge of twist angle and is accomplished by observing zero reflection wavelengths from a reflective cell with the polarizer and analyzer in cross-orientation.
REFERENCES:
patent: 3807862 (1974-04-01), Hatzenbuhler
patent: 4284354 (1981-08-01), Liao
patent: 5239365 (1993-08-01), Inoue
patent: 5532823 (1996-07-01), Fukui et al.
Kwok Hoi-Sing
Tang Shu-Tuen
Font Frank G.
Ratliff Reginald A.
The Hong Kong University of Science & Technology
LandOfFree
Method and apparatus for measuring liquid crystal cell propertie does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for measuring liquid crystal cell propertie, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for measuring liquid crystal cell propertie will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1788905