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. 29, 2018
Filed:
Mar. 06, 2017
Konica Minolta, Inc., Chiyoda-ku, JP;
Kazuhiko Inoue, Kita-ku, JP;
Yusuke Imai, Osaka, JP;
KONICA MINOLTA, INC., Tokyo, JP;
Abstract
A projection zoom lens includes, sequentially from an enlargement conjugate side: a first lens group having negative refractive power; a second lens group having positive or negative refractive power; a third lens group having positive refractive power; a fourth lens group having negative refractive power; a fifth lens group having positive refractive power; and a sixth lens group having positive refractive power, and configured to perform a magnification variation by changing the interval between the respective lens groups, wherein the fourth lens group includes at least one positive lens and at least one negative lens, at least one of the positive lenses included in the fourth lens group satisfies the following Conditional Expressions: 0.71≤θg_Fp+0.004×νdp≤0.73 and 15≤νdp≤25, and the back focus of the entire projection zoom lenses satisfies the following Conditional Expression 1.0≤BF/Fw≤2.7.