Method for testing thickness of LCD device liquid crystal layer

Abstract

The present invention provides a detecting method of the thickness of the liquid crystal layer in a liquid crystal display device, and comprises the processing as following: (1) Detecting the average inclined angle Theta of liquid crystal display devices under the different external voltages, and selecting a group of suitable incident angles Alpha and the average inclined angle Theta as the detection condition for a retardation Delta; (2) Detecting the retardation Delta of liquid crystal display devices, and recording the values used in the process of measuring the retardation Delta, of the practical incident angle Alpha and the average inclined angle Theta, and also recording the detected retardation Delta; (3) According to the refraction index of ordinary light no, the refraction index of extraordinary light ne, and the incident angles Alpha and the average inclined angle Theta used in the process of measuring the retardation Delta of liquid crystal display devices in the process (2), calculating effective double refraction coefficient Delta neff; (4) According to the retardation Delta detected and obtained in the process (2) and Delta neff calculated and obtained in the process (3), calculating and obtaining the thickness d of the liquid crystal layer in the liquid crystal display devices. The present invention can achieve the accurate value of the thickness of the liquid crystal layer, and is easy to use and low in cost.

Description

technical field [0001] The invention relates to a method for testing the thickness of a liquid crystal layer of a liquid crystal display device. Background technique [0002] The ellipsometry changes the angle of the polarizer and the analyzer to obtain different transmittances to test the retardation δ in the vertical direction of the liquid crystal display device, and then obtains the thickness of the liquid crystal layer through the following formula, namely formula (1). [0003] δ=Δnd=(n e -n o )d (1) [0004] Where Δn is the birefringence coefficient, d is the thickness of the liquid crystal layer, n e is the extraordinary refractive index, n o is the refractive index of ordinary light. [0005] The above-mentioned method for testing the thickness of the liquid crystal layer does not need the ordinary light refractive index n o , extraordinary optical refractive index n e Instead, the thickness of the liquid crystal layer is calculated directly by their differenc...

AI Technical Summary

Problems solved by technology

If the above test method is used to test a liquid crystal display device in which liquid crystal molecules are arranged obliquely, the greater the average inclination angle of the liquid crystal molecules, the lower the test accuracy of the test method for the thickness of the liquid crystal layer

[0007] At the same time, the ellipsometer has a certain test lower limit. The above test method first measures the retardation in the vertical direction of the liquid crystal display device, and then calculates the value of the thickness of the liquid crystal layer through formula (1). Therefore, for the retardation in the vertical direction is small Liquid crystal display devices, it is also difficult to achieve accurate measurement of the thickness of the liquid crystal layer

[0008] Therefore, in terms of liquid crystal layer thickness testing, for liquid crystal display devices with liquid crystal molecules arranged obliquely, or liquid crystal display devices with small retardation in the vertical direction (including liquid crystal molecules arranged obliquely and non-inclinedly), the test accuracy of the above test method is obvious. has limitations

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