Patent · US Expired

Light absorption device for the prevention of stray light in particular in a phototypesetter

US4185902A · kind A · utility

25Cited by
1References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 2, 1978
Grant dateJan 29, 1980
Priority date
Expiry dateJun 2, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B5/22
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A phototypesetter has an optical path including a beam splitter intersecting the main light path and an auxiliary light path for reflecting the auxiliary light path into the main light path. An absorption element with a concave front surface is mounted behind the beam splitter to absorb the non-reflected light from the auxiliary beam. Additionally, the concave surface directs the nonabsorbed light to a light absorbent body.

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