Electromagnetically driven shutter camera having automatic focusing device
US4508442A · kind A · utility
6Cited by
8References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 31, 1982 |
| Grant date | Apr 2, 1985 |
| Priority date | — |
| Expiry date | Aug 31, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B9/14
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Pulses through a coil in a magnetic field move the coil back and forth and cause an engagement arrangement to execute successive roundtrip movements that advance a focus control along one step for each pulse. According to an embodiment of the invention, the inertia of an exposure control is too great to follow the back and forth motion of the coil in response to these focusing pulses. However, longer exposure control pulses allow the exposure control to follow the coil motion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.