Title:
大口径比内焦望遠レンズ
Document Type and Number:
Japanese Patent JP4639635
Kind Code:
B2
Abstract:
The purpose is to provide a large-aperture-ratio internal focusing telephoto lens applicable to a wider photographing area by equipping a vibration reduction function capable to satisfactorily correct a camera shake and the like with securing superb optical performance. The large-aperture-ratio internal focusing telephoto lens includes, in order from an object, a first lens group G 1 having positive refractive power, a second lens group G 2 having negative refractive power, and a third lens group G 3 having positive refractive power. The second lens group G 2 is moved along an optical axis upon changing focus from infinity to a close-range object. The first lens group G 1 has at least two cemented lenses and satisfies a given conditional expression. Either one of the cemented lens satisfies a given conditional expression.
Inventors:
Mitsuaki Wada
Application Number:
JP2004139123A
Publication Date:
February 23, 2011
Filing Date:
May 07, 2004
Export Citation:
Assignee:
NIKON CORPORATION
International Classes:
G02B13/02; G02B9/14; G02B15/14; G02B27/64
Domestic Patent References:
| JP8327897A | ||||
| JP9145996A | ||||
| JP9325269A | ||||
| JP2000284171A |
Attorney, Agent or Firm:
Yoshio Inoue