Endoscope objective lens and endoscope
US7907352B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 8, 2008 |
| Grant date | Mar 15, 2011 |
| Priority date | — |
| Expiry date | May 21, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B23/243
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An endoscope objective lens includes, in order from an object side, a negative first lens, a first cemented lens, an aperture diaphragm, a positive fourth lens and a second cemented lens. The negative first lens has a concave surface directed to an image side. The first cemented lens is formed by cementing a second lens and a third lens. One of the second and third lenses is positive and. The other is negative. The positive fourth lens includes a flat surface or a surface having a larger absolute value in radius of curvature, directed to the object side. The second cemented lens is formed by cementing a positive fifth lens and a negative sixth lens in order from the object side. The second cemented lens has a positive refractive power as a whole. The endoscope objective lens satisfies the following conditional expressions (1) and (2).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.