Distance measuring device for use in a camera
US4464038A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 17, 1981 |
| Grant date | Aug 7, 1984 |
| Priority date | — |
| Expiry date | Dec 17, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/32
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A distance measuring device includes light emitting diode for emitting light toward a subject to be photographed, and a pair of light receiving elements spaced by a predetermined base length from the light receiving diode. The light receiving elements are position side-by-side such that the boundary therebetween extends in a direction which is perpendicular to the direction of the base length so that an image formed by the light emitted to, and reflected from, the subject, will be formed on the light receiving elements in a bridged manner. The respective areas on the light receiving elements occupied by the image differ relative to the distance to the subject. A ratio between the signal levels obtained from the light receiving elements is calculated as a signal representing the distance to the subject.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.