Image detection device having correction circuit for removing artifacts due to delayed charge transfer
US5530238A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1994 |
| Grant date | Jun 25, 1996 |
| Priority date | — |
| Expiry date | Sep 1, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image detection device, notably a semiconductor image detection array for detecting x-ray images, is provided wherein perturbations due to phantom-images are substantially mitigated. In such an image detection array incident image carrying radiation is converted into charges. Delayed charge transfer due to trapping of charges in the semiconductor material of radiation sensor elements causes such perturbations. In an image detection device according to the invention a correction circuit is provided which is arranged to form an image correction signal being representative of delayed transferred charges. In a particular embodiment of an image detection device according to the invention the image correction signal is formed as a superposition of exponentially decaying signals of images which were detected before the detection of a currently detected image. An image signal containing artifacts due to delayed charge transfer is formed by a read-out circuit whereto charges formed by the radiation sensor elements are transferred. A corrected image signal is subsequently formed from the image correction signal and the signal formed by the multiplex circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.