DETECTION OF DEFECT OF TFT SUBSTRATE AND DEFECT INSPECTION APPARATUS

摘要

PURPOSE: To provide a method for rapidly and surely detecting the defect elements of a TFT substrate and its defect inspection apparatus. CONSTITUTION: The rear surface of a TFT substrate 12 is irradiated with illuminating light L. A liquid crystal cell part 5 consisting of a liquid crystal plate 51 having polarizing films 512, 513 facing directions orthogonal with each other on its both surfaces and a grounded transparent electrode plate 52 is disposed in proximity on the front surface thereof and is provided with a line sensor 62 having photodetectors 21 and a defect detecting section 8 for the output signals S of the respective photodetectors 621. Driving voltage Vs is applied on the respective TFT elements 12a and the TFT substrate 12 is moved in the perpendicular direction of the line sensor 62. The illuminating light L is transmitted through the polarizing film 513 and is received in the photodetectors 621 by lowering or eliminating of the electric field intensity of the defective elements 12a. The output signals thereof are inputted to the defect detecting section 8, by which the respective defective elements 12a' are detected. The respective defective elements 12a' are specified by the addresses of the photodetectors 621.