Patent · US Expired

Head-up display for automobile

US4740780A · kind A · utility

158Cited by
12References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 24, 1985
Grant dateApr 26, 1988
Priority date
Expiry dateJun 24, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B2027/0169
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A head-up display for use in an automotive or other vehicle having limited space. The optical path from display symbol generator to a collimating lens is folded to fit in a relatively compact housing. Also shown is the use of the automobile windshield as a combiner glass for the display. Corrective lenses, and in particular crossed linear fresnel lenses, are used to correct for the astigmatism introduced by the geometry of the windshield. This provides a combination of optical powers for the display lens and the windshield which has the resultant effect of projecting an image from the image source to the driver's eye. The source is a high light output array of light-emitting diodes. A microprocessor based controller for detecting the status of inputs from the automobile is shown. Data is periodically loaded into a random access memory dedicated to controlling the display. When data is not being loaded, a separate address and timing generator is used to cause data from this memory to be displayed in a free-running mode.

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