Patent · US Expired

Reflection and refraction optical system and projection exposure apparatus using the same

US6229647A · kind A · utility

96Cited by
20References
59Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 11, 1997
Grant dateMay 8, 2001
Priority date
Expiry dateAug 11, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S359/90
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A reflection and refraction optical system includes a polarization beam splitter, a concave mirror, a lens group and a quarter waveplate, wherein an additional waveplate is provided to transform S-polarized light from the polarization beam splitter into circularly polarized light.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.