Active pixel image cell with embedded memory and pixel level signal processing capability
US5962844A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1997 |
| Grant date | Oct 5, 1999 |
| Priority date | — |
| Expiry date | Sep 3, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/771
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An active pixel image cell which includes a photosensor and an embedded memory element and may be used to produce signals corresponding to the photosensor outputs for successive frames. The structure of the active pixel cell includes an analog, non-volatile, or dynamic memory element and the control elements needed to store the output of the photosensor generated during a previous frame. The pixel elements then generate a signal representing the current frame output of the photosensor. The current frame output and previous frame output are then provided as output signals for the pixel and may be subjected to off-pixel processing as desired. For example, the two values may be subtracted from one another by an off-pixel difference amplifier to form a signal representing the difference between the image on the photodiode sensor of the pixel between successive frames. The difference signal may then be used for purposes of video compression, motion detection, or image stabilization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.