Optical system for endoscopes
US5793539A · kind A · utility
107Cited by
1References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 27, 1994 |
| Grant date | Aug 11, 1998 |
| Priority date | — |
| Expiry date | Dec 27, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B23/2446
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An optical system for endoscopes which comprises a stop having a variable aperture and is configured so as to produce spherical aberration for preventing an image surface thereof from being shifted in a direction opposite to the object side by narrowing the aperture of the stop, whereby the optical system is free from insufficiency in brightness and degradation in resolution thereof on a side farther from the optical system within a depth of field thereof, and has another side of the depth of field brought close to the optical system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.