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:
Jul. 29, 2025
Filed:
Jun. 07, 2022
Konica Minolta, Inc., Tokyo, JP;
Atsuo Masui, Sakai, JP;
KONICA MINOLTA, INC., Tokyo, JP;
Abstract
A variable magnification projection optical system includes, in order from an enlargement side: a first lens group having negative refractive power; a second lens group having negative refractive power; and a third lens group having positive refractive power. During zooming, the first lens group is fixed, and the second lens group and the third lens group move. The second lens group includes a plurality of lenses each having positive refractive power. All lenses each having positive refractive power in the first lens group and the second lens group are made of a glass material having a transmittance greater than 0.98 per thickness of 10 mm with respect to light having a wavelength of 440 nm.