The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 1992
Filed:
Dec. 14, 1990
Gaylord E Moss, Marina del Rey, CA (US);
John E Wreede, Monrovia, CA (US);
Kevin Yu, Temple City, CA (US);
James E Scott, Hermosa Beach, CA (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
A head-up display for a vehicle, including a primary image reflection hologram supported by a transparent substrate located in the vehicle operator's field of view for the ambient scene in front of the vehicle, a light source for providing playback illumination to the primary image hologram, and a guard hologram in front of the primary image hologram for substantially reflecting ambient illumination that otherwise could spuriously turn on the first reflection hologram, the guard hologram having an angular bandwidth and a spectral bandwidth that are greater than the angular bandwidth and the spectral bandwidth of the primary image hologram, and having an optical density of 2.0 or greater. The guard hologram can be parallel fringe reflection hologram or a slant fringe reflection hologram.