UV-absorbing filter and optical apparatus incorporating the same
US6437909B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2001 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Jun 13, 2021 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21V29/15
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A UV-absorbing filter absorbs a UV component of incoming light to reduce an amount of the UV component of transmitted light. The UV-absorbing filter comprises a transparent UV-absorbing glass plate which contains a UV-absorbing substance; a transparent first and second heat-resistant glass plates which face respective surfaces of the UV-absorbing glass plate; a first and second distance pieces which are made of heat-resistant resin and which are respectively interposed between the UV-absorbing glass plate and the first and second heat-resistant glass plates, in the vicinity of an outer edge of the UV-absorbing glass plate, so as to form a space between them.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.