Image sensors and driving method thereof
US5708471A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 4, 1995 |
| Grant date | Jan 13, 1998 |
| Priority date | — |
| Expiry date | Aug 4, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image sensor of charge storage type and a driving method of the image sensor. A light signal from a photosensitive element is read by an amplifier and the read signal is held in a sample hold circuit of a signal detector. Next, a voltage is given from a variable power source to the amplifier and a signal output from the amplifier is compared with the previously held signal in a comparator in the signal detector. The voltage of the variable power source at an equal point where the two signals are coincident with each other in the comparison is read as a true value. Hence, irrespective of dispersion of characteristics of amplifiers, the correct value can be always detected. The influences of the dispersion of the amplifiers, a temperature change and a time-drift of TFT characteristics are removed to improve S/N.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.