Patent · US Expired

Catadioptric imaging system

US5031976A · kind A · utility

86Cited by
6References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 24, 1990
Grant dateJul 16, 1991
Priority date
Expiry dateSep 24, 2010

Classification

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

Abstract

An improved catadioptric imaging system is presented which produces a flat accessible final image, and is particularly effective at high speed in the deep ultraviolet spectral range. The lenses of the system are formed from a single glass type, fused silica. A first group of lenses serves as an aberration corrector group. A single focusing lens focuses light, transmitted through the corrector group, forming an intermediate image at a predetermined position within the system. A separate field lens is placed at the intermediate image point, and focuses the light transmitted thereto through a hole in the center of a spherical mirror. The light then travels through a separate thick lens element and is subsequently reflected by a planar mirror back through the thick lens and towards the concave reflective side of the spherical mirror. The spherical mirror thereafter reflects this incident light, focusing it through a hole in the center of the planar mirror and to a final imaging point outside of the system.

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