内視鏡用対物レンズ
- 专利权人:
- オリンパスメディカルシステムズ株式会社
- 发明人:
- 笹本 勉
- 申请号：
- JP2010244111
- 公开号：
- JP5031880B2
- 申请日:
- 2010.10.29
- 申请国别(地区):
- JP
- 年份:
- 2012
- 代理人:
- 摘要：
PROBLEM TO BE SOLVED: To provide an objective lens for an endoscope for a retro-focus type that further decreases its diameter and, at the same time, copes with peripheral blur without increasing the power of the first lens.
SOLUTION: The objective lens includes, in order from an object side, a front group G1 of a negative refractive power as a whole, an aperture stop S, and a rear group G2 of a positive refractive power as a whole. The front group G1 includes, in order from the object side, a first lens L1 of negative refractive power, and a second group L2G of negative refractive power as a whole, whose face closest to the image is a concave face oriented on the image side. The second group L2G includes a single or cemented lens. The rear group G2 includes, in order from the object side, a positive lens L3 and a cemented lens composed of a positive lens L4 and a negative lens L5. In addition, the following conditional expressions are satisfied: -10&leQ1&le-2 and 0.719&le¾f
0 /f1 ¾<0.81, wherein Q1 represents the shaping factor (R2 +R1 )/(R2 -R1 ) of the second group, R1 and R2 represent the curvature radii of the faces of the second group, the faces being closest to the object and image respectively, f0 is the composite focal length of the front group, and f1 is the focal length of the first group.COPYRIGHT: (C)2011,JPO&INPIT
- 来源网站：
- 中国工程科技知识中心
