Light source device for endoscope provided with noncircular opening
US5803900A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 3, 1997 |
| Grant date | Sep 8, 1998 |
| Priority date | — |
| Expiry date | Dec 3, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0006
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A light source device for an endoscope provided with a noncircular opening which is capable of stabilizing the rate of change of the quantity of illuminating light with the quantity of movement of the stop blade and thereby preventing the hunting phenomenon of the stop blade in close-up or the like. The device comprises: a gate portion with a noncircular opening for linearly changing the quantity of light from the light source formed therein; a stop blade for controlling the quantity of light passing through the noncircular opening of the gate portion; and a motor for driving the stop blade. The noncircular opening has two V-shaped portions having different opening angles. The stop blade is provided with a circular auxiliary opening for passing part of the light therethrough. Owing to the V-shaped portions and the auxiliary opening, a change of the quantity of output light with the amount of movement of the stop blade is made linear and the hunting phenomenon of the stop blade is prevented even in the region where the quantity of light is regulated to a small quantity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.