Title:
LENS DEVICE
Document Type and Number:
WIPO Patent Application WO/2004/010195
Kind Code:
A1
Abstract:
A meniscus imaging lens (1) comprises a first concave plane (1a) positioned on a subject side, wherein Bf (back focus distance) is larger than f1 (focal distance of the entire lens system), nd (refractive index) is larger than 1.45, R1/f1 is at least -2.5 and less than zero (R1: center radius of curvature of first plane of the lens (1)), and a second plane (1b) positioned on an imaging plane side has an aspherical shape.
Inventors:
NIO JUNICHI (JP)
YOSHIDA HISATSUGU (JP)
OGINO SHUJI (JP)
YOSHIDA HISATSUGU (JP)
OGINO SHUJI (JP)
Application Number:
PCT/JP2003/009015
Publication Date:
January 29, 2004
Filing Date:
July 16, 2003
Export Citation:
Assignee:
SEIKO PRECISION KK (JP)
NIO JUNICHI (JP)
YOSHIDA HISATSUGU (JP)
OGINO SHUJI (JP)
NIO JUNICHI (JP)
YOSHIDA HISATSUGU (JP)
OGINO SHUJI (JP)
International Classes:
G02B9/02; G02B13/18; (IPC1-7): G02B13/00
Foreign References:
| EP1312941A1 | 2003-05-21 | |||
| EP1286186A2 | 2003-02-26 | |||
| JPH10213739A | 1998-08-11 | |||
| US6055105A | 2000-04-25 | |||
| JPH06250274A | 1994-09-09 | |||
| JPS6449014A | 1989-02-23 | |||
| JPH075358A | 1995-01-10 |
Attorney, Agent or Firm:
Katayama, Shuhei (6-1 Kyobashi 1-chom, Chuo-ku Tokyo, JP)
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