Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
ズームレンズおよび情報装置
Document Type and Number:
Japanese Patent JP4764644
Kind Code:
B2
Abstract:
A zoom lens, comprising: a first lens group (I) having positive refractive power, a second lens group (II) having negative refractive power, an aperture stop (S), a third lens group (III) having positive refractive power and a fourth lens group (IV) having positive refractive power, wherein the first and third lens groups (I, III) move toward the object side according to a change in magnification power as the zoom lens shifts from a wide-angle position to a telephoto position, the aperture stop (S) moves independently from the lens groups (I, III), and a following formula is satisfied: 0.30

Inventors:
Kazuyasu Ohashi
Application Number:
JP2005047214A
Publication Date:
September 07, 2011
Filing Date:
February 23, 2005
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
株式会社リコー
International Classes:
G02B15/20; G02B13/18
Domestic Patent References:
JP4296809A
JP7005361A
JP2223908A
JP63017423A
JP63180926A
JP2004258240A
JP2004212616A
Attorney, Agent or Firm:
Shogo Honda
Toru Kabayama
Shuichi Kudo