Patent · US Expired

Obturator disc for an optical transducer

US4716289A · kind A · utility

2Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 30, 1985
Grant dateDec 29, 1987
Priority date
Expiry dateApr 30, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D5/34707
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An obturator disc comprising a cylindrical element (11) of transparent plastic material provided with a unitary hub (13) by means of which it can be connected to a rotating member. To a front surface (14) of the cylindrical element there is applied, by a photographic process, a layer of opaque material in an annular zone of which there is formed a plurality of transparent windows (16) of high definition.

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