Patent · US Expired

Method of detecting coma of projection optical system

US5760879A · kind A · utility

19Cited by
7References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 5, 1995
Grant dateJun 2, 1998
Priority date
Expiry dateJul 5, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F9/70
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method of detecting coma of a projection optical system includes receiving an image of a pattern projected by the projection optical system, at at least one position along an optical axis of the projection optical system, detecting a position of at least one received pattern image, with respect to a plane perpendicular to the optical axis of the projection optical system, and determining coma of the projection optical system on the basis of the detection.

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