Patent · US Expired

Apparatus and method for remote displaying and sensing of information using shadow parallax

US4468694A · kind A · utility

59Cited by
10References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 15, 1982
Grant dateAug 28, 1984
Priority date
Expiry dateOct 15, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/037
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A scanning beam display system is used as a projection display and as a reflective flying-spot scanner using a plurality of photoreceptors to sense depth. Used as a display, the projection of a document-size image from overhead onto a work surface such as a printed form provides a naturally oriented, non-invasive display. Beam modulation and contextual subtraction permit the flying-spot function in ambient light. Used as a combination display and scanner, inherent registration of the display and data input functions permit interaction with an operator by displaying on and sensing form any document or work object. A plurality of non-overlapping sensors operate with the flying-spot function to receive images alike in perspective but differing in shadow placement, from which relative distances and object boundaries are easily derived. Used without the display function, a visualization of a work area is obtained that is much more interpretable by a computer than with standard visual parallax for improved robotic visual perception. Acting in concert, the methods of this invention form a touch sensitive image on a work surface devoid of display or sensing hardware.

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