Automatic focus adjustment circuitry for motion picture cameras
US4184753A · kind A · utility
4Cited by
1References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 1, 1978 |
| Grant date | Jan 22, 1980 |
| Priority date | — |
| Expiry date | Dec 1, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/28
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a motion picture camera, the response of a device for automatic focus adjustment is retarded, so that the change in the focus condition of the camera and the resultant change in angle of view and magnification of the image do not take place so rapidly during the photographing. An integrating circuit is provided to retard a signal indicative of out-of-focus condition, or a pulse generator is provided to intermittently power a drive motor for focus adjustment. The integrating circuit and the pulse generator are actuated concurrently with commencement of photographing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.