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. 01, 2018
Filed:
Sep. 14, 2016
Konica Minolta, Inc., Tokyo, JP;
Yusuke Imai, Osaka, JP;
Kazuhiko Inoue, Osaka, JP;
Konica Minolta, Inc., Tokyo, JP;
Abstract
A projection lens system includes a first lens group including a 1a-th lens group having a negative refractive power, a 1b-th lens group having a positive or negative refractive power, and a 1c-th lens group having a positive or negative refractive power. During a zoom, the first lens group remains stationary on an optical axis. During a focus from a remote distance side to a close distance side, the 1a-th lens group remains stationary on the optical axis while the 1b-th and 1c-th lens groups move toward the enlargement conjugate side along different loci respectively. Conditional formula −4.7<fl/fw<−2.5 is fulfilled at both the remote and close distance sides, where fl represents a focal length of the first lens group, and fw represents a focal length of the entire system at a wide-angle end.