Title:
【発明の名称】内視鏡用リレーレンズ
Document Type and Number:
Japanese Patent JP2714685
Kind Code:
B2
Abstract:
PURPOSE:To compensate an on-axis chromatic aberration and a magnification chromatic aberration and to improve resolving power by employing five-element lens constitution and satisfying specific conditions. CONSTITUTION:This relay lens comprises a cemented lens L1+L2 consisting of a 1st lens L1 and a 2nd lens L2 having a positive composite focal distance, a 3rd positive lens L3 which has a surface small in radius of curvature on the side of an image guide, a 4th positive lens L4 which has a surface small in radius of curvature on the image guide side, and a 5th negative lens L5 which has a surface small in radius of curvature on the image guide side, in order from the image guide side. In this case, the conditions shown by formula I are satisfied. Here, (v4) is the Abbe number of the 4th lens L4, (f1+2) the composite focal distance of the cemented lens L1+L2, (f1+2+3+4) the composite focal distance of the 1st lens L1 to 4th lens L4, (f3) the focal distance of the 3rd lens L3, (f4) the focal distance of the 4th lens L4, (f5) the focal distance of the 5th lens L5, and (f) the composite focal distance of the whole system. Consequently, the on-axis chromatic aberration and magnification chromatic aberration are compensated with good balance.
Inventors:
Miyano Shun
Application Number:
JP7053089A
Publication Date:
February 16, 1998
Filing Date:
March 24, 1989
Export Citation:
Assignee:
Fuji Photo Optical Co., Ltd.
International Classes:
G02B23/26; A61B1/00; G02B9/34; G02B13/04; (IPC1-7): G02B13/04; A61B1/00; G02B9/34; G02B23/26
Domestic Patent References:
| JP5880611A | ||||
| JP5162053A | ||||
| JP5149734A |
Attorney, Agent or Firm:
Michio Oshima