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. 28, 1999
Filed:
Jan. 29, 1998
Applicant:
Inventors:
Shunsuke Kimura, Nishinomiya, JP;
Masayuki Takahashi, Ibaraki, JP;
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
359651 ; 359649 ;
Abstract
A first lens group U1 having a positive optical power, a second lens group U2 having a negative optical power and a third lens group U3 having a negative optical power are disposed in the order from a screen end. For focusing action, the first lens group U1 and the second lens group U2 respectively move in a same direction for different quantities, while the third lens group U3 remains fixed. The aperture ratio of projection lens as a whole is 1:1.1, the magnification of projection is in a range of -0.025 to 0.100.