Patent · US Expired

Visual lecture aid

US5428417A · kind A · utility

85Cited by
6References
20Claims
0Family size

Inventor

Key dates

Filing dateAug 2, 1993
Grant dateJun 27, 1995
Priority date
Expiry dateAug 2, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B21/26
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An overlay projection apparatus for aiding in the communication of graphic presentations to large audiences by enabling the on-screen writing of overlay icons, highlighting bars and alpha-numeric labels as selected by the presenter. Brightness and color control of overlay highlighting graphics provide audience visual comfort over a wide variation of projected underlay graphic and ambient light conditions. Digital formation of overlay graphics by presenter/lecturer touch control command from a remote video panel also enables total storage and recall of multiple frames of complex overlay graphics with matching underlay graphics for reemphasis or for question and answer sessions between the lecturer and audience.

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