Endoscope and endoscope system with optical phase modulation member
US6984206B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 2002 |
| Grant date | Jan 10, 2006 |
| Priority date | — |
| Expiry date | Jul 26, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/555
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An endoscope system consists mainly of: an endoscope having a solid-state imaging device and an objective optical system that converges an object image on said solid-state imaging device; and a signal processing unit that processes an image signal produced by the endoscope so as to produce a video signal. The objective optical system includes an optical phase modulation member. The optical phase modulation member exhibits a response of 0.2 or more derived from an optical transfer function relative to a spatial frequency on the solid-state imaging device determined based on the Nyquist theorem, that is, a Nyquist frequency, over a wider range of distances than a depth of field offered by an objective optical system not having the optical phase modulation member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.