| 摘要 |
PROBLEM TO BE SOLVED: To obtain a convenient inspection method of evaluating the surface irregularities of a glass substrate without touching the surface. SOLUTION: A glass substrate is mounted on a steam generator, e.g. a thermostatic bath filled with hot water, while directing the rear side of a surface for inspecting surface irregularities downward. The glass substrate is then irradiated with parallel light from the inspection surface side under a state where micro water drops, produced through condensation of steam, are adhering to the rear surface. Reflected light is projected onto a screen and the incident angle of the parallel light is measured when a light/dark pattern caused by the surface irregularities disappears from a reflection image obtained by projecting the reflected light onto the screen thus inspecting surface irregularities on the inspection surface of the glass substrate.
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