Electronic timepiece having illumination level
US4423963A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 15, 1982 |
| Grant date | Jan 3, 1984 |
| Priority date | — |
| Expiry date | Sep 15, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G9/0088
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electronic timepiece is provided with a photo-electric cell generating an output voltage indicative of incident illumination levels, circuit means for converting this output voltage into digital data signals, and a liquid crystal display which is driven in response to the data signals such that successive sections of the display act to progressively unmask a rear reflector plate to thereby indicate the illumination level. The circuits for converting illumination level to data signals are based on an oscillator circuit whose frequency is controlled by the photo-electric cell voltage, and digital means for measuring this frequency, so that the circuit configuration is very simple and power comsumption extremely low.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.