Endoscopic objective lens and endoscope
US9442283B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 21, 2015 |
| Grant date | Sep 13, 2016 |
| Priority date | — |
| Expiry date | Mar 1, 2035 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B1/00096
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An endoscopic objective lens consists of a negative first lens group, a stop, and a positive second lens group, disposed in order from the object side. The first lens group is composed of a cemented lens formed of a first lens and a second lens with a concave surface on the image side cemented in order from the object side. The second lens group is composed of a positive single third lens and a cemented lens formed of a fourth lens and a fifth lens, either of which being a positive lens and the other being a negative lens, and having a positive refractive power, disposed in order from the object side. The endoscopic objective lens satisfies given conditional expressions related to Abbe numbers of the first and second lenses and radii of curvature of the image side and object side surfaces of the second lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.