Patent · US Expired

Optical unit, exposure unit and optical devices

US7184227B2 · kind B2 · utility

2Cited by
6References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 6, 2006
Grant dateFeb 27, 2007
Priority date
Expiry dateApr 6, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70825
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In an optical unit having a holding structure which brings a junk ring or the like into contact with an optical surface of a lens, the optical surface suffers from a serious elastic deformation leading to deterioration of optical performance. Upon holding the lens, therefore, a face other than the optical surface is provided on the lens so that the lens is held by applying a force to the face from element holding members.

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