| 摘要 |
PURPOSE:To inspect optical materials easily, accurately and quickly by varying the incident angle of light to an inspecting box having an inner side surface of high reflectivity, a bottom surface of high absorbance, and windows for holding the objects to be inspected. CONSTITUTION:A quartz plate 1 is mounted to a holder 2 and is cleaned, and each of these holders 2 is mounted to an inspecting box 3. The side surface in the box 3 is a surface of high reflectivity, and a bottom surface 7 is a surface of high absorbance and is an inspection surface. To examine the internal defects of the quartz plates 1, a light source part 4 consisting of a fluorescent lamp 5 and a reflection plate 6 is adjusted to tilt to the extent of lighting for the bottom surface 7, and the bottom surface of the box 3 is viewed from above through the main surfaces of the plates 1. To examine the defects on the surfaces, the main surfaces of the plates 1 are viewed from the position which is about 45 deg.C to the main surfaces of the plates 1. Thereby, the inclusions in the quartz plates are viewed as luminous spots, and the fogging owing to washing flaws and the fogging owing to insufficient polishing are inspected by the reflection states of the main surfaces. |
