Shutter assembly for photographing devices with precision timing facility
US4306796A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 6, 1980 |
| Grant date | Dec 22, 1981 |
| Priority date | — |
| Expiry date | Aug 6, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B42/02
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A between-lens shutter assembly for photographing devices comprising at least two, preferably three rotary plates with axes parallel to the axis of the lenses. Each plate comprises an opening. When the plates are rotated with common speed, the openings move from evenly distributed directions towards the inside opening of the lenses, completely uncover it, then in continued movement close the inside opening again. This way identical opening and closing characteristics and times are provided. In a method using the shutter assembly exposures are taken from television pictures, in which the length of the exposure period is adjusted to be equal to the period of a television picture and the duration of either an opening or closing section, whereby uniform illumination is ensured for the exposure. The invention can be used mainly for the precise photographing of X-ray pictures displayed on the screen of a television monitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.