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:
Feb. 02, 1999
Filed:
Sep. 30, 1994
Robert D Williams, Agoura Hills, CA (US);
Daniel M Battista, Hawthorne, CA (US);
Alan J Reuter, Lawndale, CA (US);
John J Ferrer, Tehachape, CA (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
A low cost, compact projection display source that serves as a very bright image source for an automotive head up display. The present invention is comprised of a high intensity halogen light source and a liquid crystal display. The liquid crystal display is controlled by display electronics that write images onto the liquid crystal display that are to be displayed to the driver or passengers of a vehicle. Light output from the high intensity light source is transmitted through a piece of infrared energy absorbing glass, a decentered lens, such as a Fresnel lens, and a diffuser that uniformly backlights the liquid crystal display. Crossed polarizers are used on either side of the liquid crystal display. The high intensity light output transmitted by the liquid crystal display is passed through a yellow-orange output window which is projected onto a toric combiner for display to the driver of the vehicle. A fan provides cooling for the liquid crystal display and display circuitry that interfaces between the display electronics and the liquid crystal display. The projection display source produces a very high contrast (very bright) image source without heat problems. The projection display source is capable of producing 20,000 foot-lamberts of light energy output. The projection display source is the brightest known image source for non-military head up displays of either the non-reconfigurable or reconfigurable variety. The yellow-orange color used for the output window of the projection display source is used to maximize color contrast with the display background.