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:
Dec. 25, 1990
Filed:
Jan. 24, 1990
Hong C Park, Seoul, KR;
Goldstar Co., Ltd., Seoul, KR;
Abstract
A rear projection screen having a wide-ranged extinguishing rate in which an area of portion for extinguishing the illumination light from exterior of the rear side of screen is widened so that the high contrast can be maintained, which includes a first sheet formed with Fresnel's lens and a second sheet having primary cylindrical lenticules at one side surface and secondary cylindrical lenticules at the other side surface, wherein a focus distance of the primary cylindrical lenticule is made to n/S1(n- 1) and the focus distance thereof is set larger than the distance between the top point of the primary lenticule and the center point of the secondary lenticule whereby clear pictures on the screen can be obtained without lowering the contrast even under an illumination light from exterior.