Method and apparatus for measuring melt level
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
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Feb 7, 2006
Grant Date -
Jun 26, 2003
app pub date -
May 1, 2001
filing date -
May 1, 2000
priority date (Note) -
In Force
status (Latency Note)
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Abstract
A melt level or the gap between a melt surface and a heat shield is measured accurately irrespective of how the melt surface is. A laser beam from a range-finding unit is reflected by a scanning mirror and projected on a melt surface through an entrance window and a quartz prism in a chamber of a puller. After specular reflection, the beam forms a measurement spot in the bottom of a heat shield and scatters. Part of the scatter, after specular reflection at the melt surface (secondary reflection), passes through the prism, the entrance window and the scanning mirror to the range-finding unit. The range-finding unit carries out triangulation using the distance between a laser source and a photodetector therein, and the angle of incidence and the angle of the received laser beam.
First Claim
Other Claims data not available
Family
| Country | kind | publication No. | Filing Date |
|---|---|---|---|
| TW | B | TW546423 | Apr 30, 2001 |
| WO | A1 | WO2001083859 | May 01, 2001 |
| EP | B1 | EP1279752 | May 01, 2001 |
| JP | B2 | JP4733900 | May 01, 2001 |
| KR | B1 | KR100720660 | May 01, 2001 |
International Classification(s)
- 2001 Application Filing Year
- C30B Class
- 421 Applications Filed
- 172 Patents Issued To-Date
- 40.86 % Issued To-Date
Cited Art Landscape
Patent Citation Ranking
- 3 Citation Count
- C30B Class
- 1.59 % this patent is cited more than
- 19 Age
