Method and apparatus for detecting melt level
US6572699B1 · kind B1 · utility
4Cited by
5References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 14, 2001 |
| Grant date | Jun 3, 2003 |
| Priority date | — |
| Expiry date | Sep 14, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1068
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A melt level detector is provided for detecting the melt level of a CZ furnace by triangulation. The laser beam (2) from a laser source (1) is moved in radial directions of a crucible (14) in the CZ furnace to find a location where a photodetector system (5, 7) can receive the reflection (4) from the melt level (3), and the laser beam (2) is fixed at the location. Since the measurements thus take place within an extremely small angular range of the laser beam, the melt level (3) can be detected with little effect of noise on the melt level (3) while eliminating complexity of the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.