VITREOUS SILICA CRUCIBLE AND DISTORTION-MEASURING APPARATUS FOR THE SAME

摘要

In an embodiment, a distortion-measuring apparatus for measuring a distortion distribution of an entire vitreous silica crucible in a non-destructive way includes: a light source 11; a first polarizer 12 and a first quarter-wave plate 13 disposed between the light source 11 and an outer surface of a vitreous silica crucible wall; a camera 14 disposed inside of a vitreous silica crucible 1; a camera control mechanism 15 configured to control a photographing direction of the camera 14; a second polarizer 16 and a second quarter-wave plate 17 disposed between the camera 14 and an inner surface of the vitreous silica crucible wall. An optical axis of the second quarter-wave plate 17 inclines 90 degrees with respect to the first quarter-wave plate 13.

主权项

1. A distortion-measuring apparatus of a vitreous silica crucible, in which the crucible includes an opaque outer layer containing a plurality of bubbles and a transparent inner layer with bubbles removed, the distortion-measuring apparatus comprising:
a light source disposed outside of the vitreous silica crucible; a first polarizer disposed between the light source and an outer surface of the vitreous silica crucible's wall; a first quarter-wave plate disposed between the first polarizer and the outer surface of the vitreous silica crucible wall; a camera disposed inside of the vitreous silica crucible; a camera control mechanism configured to control a photographing direction of the camera; a second polarizer disposed between the camera and an inner surface of the vitreous silica crucible wall; and a second quarter-wave plate disposed between the camera and the inner surface of the vitreous silica crucible wall with an optical axis inclined 90 degrees with respect to the first quarter-wave plate; wherein the camera conducts color photographing of light which is emitted from the light source and passes through the first polarizer, the first quarter-wave plate, the wall of the vitreous silica crucible, the second quarter-wave plate, and the second polarizer.