Still photographic or movie camera
US4064520A · kind A · utility
7Cited by
1References
23Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Apr 28, 1975 |
| Grant date | Dec 20, 1977 |
| Priority date | — |
| Expiry date | Apr 28, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B19/18
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A camera having a forward lens unit including a displaceable lens for providing a variable focal length, a film plane, a base objective having a fixed focal length, and an aperture diaphragm between the displaceable lens and the film plane together with automatic drive means for displacing the base objective axially in direct proportion to the diaphragm stop of the aperture diaphragm to thereby shift the image plane defined by the forward lens unit and the base objective and provide a substantially constant circle of diffusion at the film plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.