Vitreous silica crucible and distortion-measuring apparatus for the same
US9816917B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 25, 2014 |
| Grant date | Nov 14, 2017 |
| Priority date | — |
| Expiry date | Dec 25, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0683
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.