Semiconductor color sensor detection circuit
US4692025A · kind A · utility
7Cited by
1References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 14, 1985 |
| Grant date | Sep 8, 1987 |
| Priority date | — |
| Expiry date | May 14, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2005/607
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a semiconductor color sensor circuit with two photodiodes having mutually different wavelength sensitivity characteristics, the ratio of numbers or areas of two types of transistors for logarithmic compression of signals from these photodiodes is adjusted so that errors in output voltage due to changes in temperature can be reduced and the dynamic range of illuminance of incident light can be enlarged.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.