Corrosion-resistant alumina member and arc tube for high-intensity discharge lamp
US6642656B2 · kind B2 · utility
1Cited by
24References
5Claims
0Family size
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Key dates
| Filing date | Mar 27, 2001 |
| Grant date | Nov 4, 2003 |
| Priority date | — |
| Expiry date | May 7, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An arc tube is formed by polycrystalline alumina so that an average crystal grain diameter of a surface is two to ten times as large as an average crystal grain diameter of an inside including a center line of a thickness and the average crystal grain diameter on the center portion of the thickness is 10 &mgr;m to 100 &mgr;m. As a result, in the arc tube, the total transmittance is 98%, and a linear ray transmittance is 5%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.