Title:
望遠レンズ
Document Type and Number:
Japanese Patent JP5101878
Kind Code:
B2
Abstract:
To provide a lens system advantageous for downsizing a moving group and suitable for large aperture ratio formation and ultra telescopic formation while maintaining an excellent optical function from a long distance to a close range. A first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, and a fourth lens group having a negative refracting power are provided in order from an object side. The first lens group includes a first sub group and a second sub group. The second sub group is provided with a refracting power stronger than that of the first sub group and a following condition equation is satisfied. 1.5 where, f1a denotes a focal length of the first sub group and f1b denotes a focal length of the second sub group.
Inventors:
Kazunori Ohno
Application Number:
JP2006355291A
Publication Date:
December 19, 2012
Filing Date:
December 28, 2006
Export Citation:
Assignee:
FUJIFILM Corporation
International Classes:
G02B13/02
Domestic Patent References:
| JP11119092A |
Attorney, Agent or Firm:
Yanagita Seiji
Go Sakuma
Go Sakuma