| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enhance detection accuracy of an internal defect of a glass substrate by detecting an edge thereof even when a fluorescent light portion image is a haze-like image due to the internal defect of the glass substrate. <P>SOLUTION: A manufacturing method of a mask blank glass substrate includes: a substrate preparation process for preparing a glass substrate having two main surfaces and four end surfaces when manufacturing the mask blank glass substrate; and a defect inspection process for detecting an internal defect by introducing inspection light having a wavelength of 200 nm or shorter into the glass substrate from any surface thereof. The defect inspection process determines whether or not fluorescent light generated due to the internal defect of the glass substrate exists by the inspection light and selects the glass substrate being determined that the fluorescent light does not exist by photographing the glass substrate from the any surface thereof and by performing image processing including a process for obtaining a light quantity difference by means of a remote difference with respect to the image being photographed. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
