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:
Jun. 22, 1999
Filed:
Oct. 30, 1997
Applicant:
Inventors:
Shunta Takimoto, Sakai, JP;
Katsuhiro Takamoto, Sakai, JP;
Assignee:
Minolta Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
359686 ; 359689 ;
Abstract
A Zoom lens system, from the enlargement side, has the first to fourth lens units having the negative, positive, negative, positive optical power, respectively. The third lens unit has a meniscus lens having a convex surface on the enlargement side. The fourth lens unit has two positive lenses. During zooming from the shortest focal length condition to the longest focal length condition, the second and third lens units move along the optical axis so that a distance between the second and third lens units increases and a distance between the third and fourth lens units decreases. The zoom lens system fulfills the following conditions: