INSPECTION METHOD FOR SUBSTRATE FOR PLASMA DISPLAY PANEL

PROBLEM TO BE SOLVED: To provide an inspection method for a substrate for a plasma display panel that allows quality discrimination through easy and reliable detection of positions of air bubbles present in a dielectric layer in a three-dimensional space. SOLUTION: The inspection method comprises a step 1 of applying light to the substrate for a plasma display panel by coaxial vertical illumination and detecting the reflected light resulting therefrom by an optical sensor; a step 2 of extracting a defective portion, by analyzing data obtained in the step 1 and obtaining characteristic data on the defective portion; a step 3 of applying light to the substrate by oblique illumination and detecting the reflected light resulting therefrom by using an optical sensor; a step 4 of extracting a defective portion, by analyzing data obtained in the step 3 and obtaining the characteristic data on the defective portion; and a step 5 of identifying the positions of the defective portions extracted in the step 2 and step 4 respectively and evaluating the dielectric layer by using the characteristic data on the defective portions located at the same positions. COPYRIGHT: (C)2006,JPO&NCIPI