Patent · US Expired

Method and apparatus for adjusting the optical alignment of a film projection system

US5257051A · kind A · utility

15Cited by
6References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 24, 1992
Grant dateOct 26, 1993
Priority date
Expiry dateDec 24, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B21/28
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method and apparatus for adjusting the optical alignment of a film projection system of the type having a film gate with a central opening, a lens mount having lenses optically aligned along an optical axis of the lens mount, a light source and a generally ellipsoidal collector for reflecting light from the light source along an optical axis of the collector. The method and apparatus utilize a laser light source which is inserted in the position normally occupied by the lenses and a beam splitter which splits the beam of laser light into a center beam and two inclined side beams. An intercept sheet is temporarily placed in the path of the center beam and reflections of the side beams from the interior surface of the collector to create images of the center beam and the reflected side beams on the intercept sheet. By adjustment of the position and tilt of the collector, the images of the center beam and the reflected side beams on the intercept sheet can be brought into coincidence, thereby bringing the optical axes of the collector, the film gate and the lens mount into coincidence with a system optical axis in which the illumination is centered upon the opening through the film …

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