Patent · US Expired

Automobile head-up display system with reflective aspheric surface

US4961625A · kind A · utility

313Cited by
22References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 15, 1989
Grant dateOct 9, 1990
Priority date
Expiry dateSep 15, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B2027/0187
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An optical display system (10) presents visual source information to an observer (18). The display system includes a vision unit (14) that has reflective surfaces (16) through which the observer can view an outside world scene and which reflect source information emanating from an information source (22) for display to the observer. In a preferred embodiment, the optical display system constitutes a head-up display system for an automobile and the observer is the driver of the automobile. The vision unit constitutes an automobile windshield with or without a reflection enhancement material and whose inner and outer surfaces reflect source information carried by light propagating from the information source, such as a liquid crystal display (32). A projection lens system (24) positioned between the inner surface of the windshield and the information source has optical light-directing properties for compensating for optical aberrations introduced by the nonplanar windshield surface. The projection lens system includes an aspheric element (262) that is unique to a specific aspheric windshield shape and remaining elements that are common to a great number of different windshield shapes…

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