Patent · US Expired

Adjusting method and apparatus for positioning planar components

US4252442A · kind A · utility

7Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 3, 1979
Grant dateFeb 24, 1981
Priority date
Expiry dateApr 3, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/133354
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method and apparatus for mutually adjusting the positioning of planar, generally transparent components such as for example, small liquid-crystal plates. The plates are provided with marks specially structured to diffract incident collimated light, in a shape or direction which is characteristic for each plate. By means of a convergent lens, characteristic diffraction images produced by passing light through the marks are depicted on a detector located in the image plane of the convergent lens. The respective characteristic images of the marks are stopped down individually by means of a diaphragm located in the lens focal plane. The diaphragm can periodically be closed partially, so that control signals for the electronic displacement of each plate can be derived individually from the particular positions of the images of the marks on the detector, corresponding to the positions of the plates.

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