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:
May. 02, 1989
Filed:
Jan. 20, 1987
Lacy G Cook, El Segundo, CA (US);
Gerard M Perron, Culver City, CA (US);
Brian K Zellers, Hawthorne, CA (US);
Brian D Cohn, Garrett, IN (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
A head-up display for use in a vehicle is provided with a curved combiner which reflects an image from a cathode ray tube (CRT) as collimated rays to a viewing site. A relay lens is positioned between the CRT and the combiner to magnify and transfer the image. The combiner may be a partially-reflecting mirror or holographic optical element or dielectric laminate. Included within the relay lens is a coma-control plate having two-dimensional undulations described mathematically by a two-dimensional power series having odd symmetry in a plane of a tilting of the combiner and even symmetry in the perpendicular dimension. The coma-control plate substantially reduces coma in an image presented for viewing at infinity, the coma being introduced by the curvature and off-axis use of a surface of the combiner.