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. 26, 1989
Filed:
Feb. 25, 1986
Norikazu Arai, Komae, JP;
Konishiroku Photo Industry Co., Ltd., Tokyo, JP;
Abstract
A projection lens for a three-tube television projector of the type in which three CRT's of blue, green and red are projected on the screen. The projection lens comprises a plastic first lens having an extremely small refracting power, a glass second lens, a plastic third lens and a plastic fourth lens disposed immediately before a face plate of CRT. There are large spaces between the first lens and the second lens and between the third lens and the fourth lens so that reflecting mirrors may respectively be arranged therebetween. For reducing the cost, the fourth lens can be formed from a liquid lens filled with a liquid between a thin-wall shell and a face plate.