Objective lens system for endoscopes
US5359456A · kind A · utility
137Cited by
2References
24Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 15, 1992 |
| Grant date | Oct 25, 1994 |
| Priority date | — |
| Expiry date | Oct 15, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B23/243
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An objective lens system for endoscopes comprising, in order from the object side, a front lens unit having a negative refractive power, an aperture stop and a rear lens unit having a positive refractive power. This objective lens system is compact, comprises a small number of lens elements and favorably corrected aberrations, especially chromatic aberration, owing to a fact that at least one graded refractive index lens component is used in the front lens unit or the rear lens unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.