Apparatus and method preventing radiation induced degradation of optical elements
US4641033A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1984 |
| Grant date | Feb 3, 1987 |
| Priority date | — |
| Expiry date | Dec 19, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J65/044
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for maintaining an optical element at a sufficiently high temperature during transmission of radiation by the optical element to prevent radiation degradation of the optical element by an increase in the absorption of at least one wavelength of the radiation. The material of the optical element is such that the absorption of the wavelength(s) concerned temporarily decreases upon annealing the optical element. The optical element may be kept at the temperature required by a wide variety of heating techniques, including gas convection heating, direct contact heating, and radiant heating. The heated optical element may be employed in optical systems for transmitting radiation from a source of radiation to a target to be exposed to this radiation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.