Beam parameter monitoring unit for a molecular fluorine (F2) laser
US6529533B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 14, 2000 |
| Grant date | Mar 4, 2003 |
| Priority date | — |
| Expiry date | Apr 4, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/2258
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A beam parameter monitoring unit is provided for use with a F2 laser system including means for filtering the red light from the VUV light of a beam portion split off from the mainbeam of the F2 laser before the beam portion reaches a detector. The filtering means includes a mirror that is highly reflective of VUV light (“VUV HR mirror”), particularly around 157 nm, and transparent to red light. The VUV HR mirror reflects the VUV light to a detector such that the properties and parameters of the main beam can be monitored, adjusted, controlled and/or stabilized. The VUV HR mirror is preferably surrounded by a shield for absorbing the red light transmitted through or around the VUV HR mirror. Also preferably, an aperture is provided that is just wide enough to permit the VUV radiation to substantially pass through, and to block the outer portions of the incident beam portion including substantially only red light. In addition, the beam parameter monitoring unit is enclosed in a sealed enclosure free of species that absorb VUV light such as oxygen, water vapor and hydrocarbons.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.