Diaphragm control system
US4336990A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 4, 1980 |
| Grant date | Jun 29, 1982 |
| Priority date | — |
| Expiry date | Nov 4, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B9/07
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A control system for diaphragms of photographic cameras, of the type where the diaphragm is in a lens assembly interchangeably mounted on the camera, and the camera contains mechanism for controlling the aperture of the diaphragm. The diaphragm blades are moved, for adjusting the aperture, by rotation of the usual slotted ring, and the movement of this ring is non-linear; that is, the ring does not turn through equal distances in order to produce aperture changes through successive equal increments of the usual diaphragm aperture scale. The movements of the aperture determining mechanism within the camera body, however, are linear. According to the invention, the interchangeable lens assembly containing the diaphragm has a finger which engages the mechanism in the camera on which the assembly is mounted and which partakes of linear movements in accordance with the movements of the mechanism in the camera. This finger is coupled through a pivoted member controlled by a cam to the slotted ring which moves the diaphragm blades, so that the linear movement produced by the camera mechanism is transformed into a non-linear movement of the slotted ring in the interchangeable lens assembly…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.