Active pixel intraoral radiological image sensor and associated image capture method
US11806180B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 2020 |
| Grant date | Nov 7, 2023 |
| Priority date | — |
| Expiry date | Jul 14, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/63
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The subject matter of the invention is an active pixel dental radiological image sensor, with integrated X-ray occurrence detection, which uses the pixels of the matrix to detect the start of an X-ray flash, by detecting the current produced by all the photodiodes in the matrix. A switching circuit MUX1 thus allows, in a first phase of detecting the start of an X-ray flash, a common connection node NC to be connected that corresponds to the drain of a photodiode initialisation transistor M1 at the input of a current-voltage conversion detection circuit DTX1, which provides as output a signal for detecting the start of an X-ray flash when the current produced by all the photodiodes of the matrix exceeds a predetermined threshold. The switching circuit MUX1 is then controlled to connect the common connection node NC of the pixels to a photodiode re-initialisation voltage source, VRS. In an alternative embodiment, some pixels of the matrix can be used to detect the end of an X-ray flash using the same principle, by injecting the current produced by the photodiodes of these pixels that is collected on a different common connection node, electrically isolated from the first, with the en…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.