Imaging device
US7477299B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 2005 |
| Grant date | Jan 13, 2009 |
| Priority date | — |
| Expiry date | Mar 2, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/65
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A second source follower circuit of a reference voltage generator includes a transistor having the same characteristics as a first source follower circuit of a pixel. Accordingly, the second source follower circuit can generate a second reference voltage according to the change in characteristics of the first source follower circuit. A noise voltage switching circuit outputs a first voltage as a noise voltage to a pixel signal generator when the noise voltage is equal to or lower than the second reference voltage. In a reset state, the noise voltage and the second reference voltage always have a predetermined voltage difference. Therefore, deterioration in image quality can be prevented even when capturing a subject having high brightness. Since a trimming circuit or the like selecting any one of a plurality of reference voltages according to characteristics of a formed transistor becomes unnecessary, the cost of an imaging device can be reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.