Patent · US Expired

Computer light pen interface system

US5877752A · kind A · utility

20Cited by
5References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1997
Grant dateMar 2, 1999
Priority date
Expiry dateMay 30, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/0386
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A light pen computer interface system utilizes a coil located externally of the computer's CRT display monitor to sense the magnetic field which provides the raster for the CRT. Vertical and horizontal sync detection circuits receive the sensor coil output and supply vertical and horizontal sync signals to a timing circuit. The timing circuit in response to an output signal from the light pen and the vertical and horizontal sync signals supplies a pen position signal to the computer which is either representative of the x,y coordinates position of the light pen on the CRT screen or representative of the change of x,y coordinates between successive positions of the light pen.

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