Electronic watch having a non-moving means of control
US4468131A · kind A · utility
23Cited by
1References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 3, 1982 |
| Grant date | Aug 28, 1984 |
| Priority date | — |
| Expiry date | May 3, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G21/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electronic watch having a case and a case back, a digital display, an integrated circuit, a battery and a fixed photo-electric pick-off placed on the module facing a window. The pick-off is for preference a photo-diode and its functioning is controlled by obstructing with a finger the window so as to prevent the ambient light from lighting the pick-off. According to the invention, the control system of the watch has the advantage of being insensitive to electrical parasites, of consuming little current, of being only slightly dependent upon the intensity of ambient light and of being simple to fabricate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.