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. 07, 2010
Filed:
Sep. 11, 2006
Shinichi Mihara, Tama, JP;
Kanato Adachi, Kawasaki, JP;
Keisuke Ichikawa, Hachioji, JP;
Yasunobu Iga, Hachioji, JP;
Koji Matsumoto, Hachioji, JP;
Kazuaki Murayama, Hachioji, JP;
Keigo Matsuo, Hachioji, JP;
Hideki Nagata, Hachioji, JP;
Shinichi Mihara, Tama, JP;
Kanato Adachi, Kawasaki, JP;
Keisuke Ichikawa, Hachioji, JP;
Yasunobu Iga, Hachioji, JP;
Koji Matsumoto, Hachioji, JP;
Kazuaki Murayama, Hachioji, JP;
Keigo Matsuo, Hachioji, JP;
Hideki Nagata, Hachioji, JP;
Olympus Corporation, Tokyo, JP;
Abstract
In an image forming optical system having a positive lens group, a negative lens group, and an aperture stop, the positive lens group being disposed at an image-plane side of the aperture stop and having a cemented lens, and when a straight line indicated by Nd=α×νd+β (where, α=−0.017) is set, Nd and νd of at least one lens forming the cemented lens are included in both an area which is determined by a line when a lower limit value is in a range of a following conditional expression (1), and a line when an upper limit value is in a range of the following conditional expression (1), and in an area determined by following conditional expressions (2) and (3)1.45<β<2.15  (1)1.30<Nd<2.20  (2)3<νd<25  (3) Here, Nd denotes a refractive index, and νd denotes an Abbe's number.