| 摘要 |
PROBLEM TO BE SOLVED: To measure liquid crystal layer thickness and twist angle of a twisted nematic liquid crystal cell with high precision. SOLUTION: The method for measuring utilizes an optical system which consists of a pair of polarizing plates 1, 2 having optical axes parallel to each other located so as to hold a liquid crystal cell 3 to be measured between them. The first chromaticity is calculated based on spectral distribution of a transmitted light measured by locating the optical axes of the polarizing plates 1, 2 in a direction of an orientation processing of a substrate at an incident light side of the liquid crystal cell 3 and the first angle of inclination of a straight line connecting the first chromaticity point and the achromatic point expressed on the chromaticity diagram is sought. Subsequently the second chromaticity is calculated based on spectral distribution of a transmitted light measured by locating the optical axes of the polarizing plates 1, 2 in a direction intersecting with about 45 deg. angle the direction of the orientation processing of the substrate at the incident light side and the second angle of inclination of a straight line connecting the second chromaticity point and the achromatic point is sought on the chromaticity diagram. Based on the first and the second angles of inclination a cell gap and twist angle of the TN(twisted nematic) liquid crystal cell 3 to be measured are obtained. |
