Objective optical system and endoscope
US7843655B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 2, 2009 |
| Grant date | Nov 30, 2010 |
| Priority date | — |
| Expiry date | Jul 17, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B23/243
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An objective optical system includes, a first group having positive refractive power, a second group having positive refractive power, the first group having a first parallel flat plate, a diaphragm, a second parallel flat plate and a first plano-convex lens with its convex surface facing the image side in the above mentioned order as viewed from the object side, the first parallel flat plate, the second flat parallel plate and the first plano-convex lens forming a cemented lens, the second parallel flat plate being formed by an infrared absorption filter, the second group having a second plano-convex lens with its convex surface facing the object side.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.