Title:
IMAGE FORMING OPTICAL SYSTEM AND ELECTRONIC IMAGING DEVICE HAVING THE SAME
Document Type and Number:
WIPO Patent Application WO/2007/032505
Kind Code:
A1
Abstract:
An image forming optical system includes a positive lens group, a negative lens
group, and a diaphragm. The positive lens group is arranged at the image side than
the diaphragm. The positive lens group has a cemented lens obtained by cementing
a plurality of lenses. In an orthogonal coordinate system having a horizontal
axis Nd and a vertical axis νd, when a straight line expressed by Nd = α
× νd + β (wherein α = -0.017) is set, the Nd and νd
of at least one of the lenses constituting the cemented lens are contained in both
of the regions: one region defined by a straight line as the lower limit and a straight
line as the upper limit of the range of the condition expression [1] given below;
and the other region defined by the condition expressions [2] and [3] given below.
1.45 <β < 2.15 ... [1] 1.30 < Nd < 2.20 ... [2] 3 <νd
< 12 ... [3] wherein Nd represents the refractivity and νd represents
the Abbe number.
Inventors:
MIHARA SHINICHI (JP)
ADACHI KANATO (JP)
ICHIKAWA KEISUKE (JP)
IGA YASUNOBU (JP)
MATSUMOTO KOJI (JP)
MURAYAMA KAZUAKI (JP)
MATSUO KEIGO (JP)
NAGATA HIDEKI (JP)
ADACHI KANATO (JP)
ICHIKAWA KEISUKE (JP)
IGA YASUNOBU (JP)
MATSUMOTO KOJI (JP)
MURAYAMA KAZUAKI (JP)
MATSUO KEIGO (JP)
NAGATA HIDEKI (JP)
Application Number:
PCT/JP2006/318441
Publication Date:
March 22, 2007
Filing Date:
September 11, 2006
Export Citation:
Assignee:
OLYMPUS CORP (JP)
MIHARA SHINICHI (JP)
ADACHI KANATO (JP)
ICHIKAWA KEISUKE (JP)
IGA YASUNOBU (JP)
MATSUMOTO KOJI (JP)
MURAYAMA KAZUAKI (JP)
MATSUO KEIGO (JP)
NAGATA HIDEKI (JP)
MIHARA SHINICHI (JP)
ADACHI KANATO (JP)
ICHIKAWA KEISUKE (JP)
IGA YASUNOBU (JP)
MATSUMOTO KOJI (JP)
MURAYAMA KAZUAKI (JP)
MATSUO KEIGO (JP)
NAGATA HIDEKI (JP)
International Classes:
G02B15/20; G02B13/18
Foreign References:
| JP2001033701A | 2001-02-09 | |||
| JPH08320434A | 1996-12-03 | |||
| JP2000305014A | 2000-11-02 | |||
| JPH07209582A | 1995-08-11 | |||
| JP2004069808A | 2004-03-04 | |||
| JP2004264786A | 2004-09-24 | |||
| JP2005181499A | 2005-07-07 |
Attorney, Agent or Firm:
SAITO, Keisuke (8-5 Iidabashi 2-chome, Chiyoda-k, Tokyo 72, JP)
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