Patent · US Expired

Film constraint and film writing system

US4973150A · kind A · utility

4Cited by
22References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 23, 1990
Grant dateNov 27, 1990
Priority date
Expiry dateMar 23, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N2201/0408
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A rigid cylinder is rotated about its axis of symmetry at a relatively high rate of speed by means of a motor. Around a portion of the circumference of the rotating cylinder is wrapped a flexible imaging medium such as photographic film, to which is applied longitudinal tension through means of a film transport. The film conforms to the curvature of the drum, but is held a small distance above the surface of the cylinder in equilibrium between the aerodynamic forces created by the rotating cylinder and the applied tension of the film transport, thus effecting a compliant surface air bearing. A scanning beam is used to write on the film in the line direction. Longitudinal movement of the film is used to affect scanning in the page direction.

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