Light measuring devices for cameras with automatic exposure control
US4170410A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 1977 |
| Grant date | Oct 9, 1979 |
| Priority date | — |
| Expiry date | Feb 15, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B7/09974
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A light measuring device for a camera with automatic exposure control is provided with a light responsive element and a light reflecting optical element, such as a mirror or a transparent block having a light reflecting surface, both elements being disposed outside of the light path from the objective lens to the focal plane for exposure of the film. The light reflecting optical element faces a certain area of the focal plane to receive the light reflected at the surface of the leading shutter member of a focal plane shutter device and/or the surface of the film. The light responsive element faces the optical element to receive the light reflected thereby.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.