Electromagnetic wave detection arrangement with capacitive feedback
US7173230B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 5, 2002 |
| Grant date | Feb 6, 2007 |
| Priority date | — |
| Expiry date | Sep 5, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/79
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An approach is provided for detecting EM waves using a photodetector coupled to an amplifier stage. The amplifier stage uses capacitive feedback to reduce or cancel intrinsic capacitance of the photodetector. A variety of capacitance structures may be used to provide the capacitive feedback such as shielded capacitors and capacitor arrays. The amplifier stage may be either single-ended or fully differential, depending upon the requirements of a particular application. Noise cancellation circuitry may also be included to reduce noise and offset sources present in the amplifier stage. The approach is applicable to a variety of contexts and applications. Example applications include, without limitation, detection of both brightness and Time of Flight (TOF) in 3D sensing applications. The approach may also be used to detect EM wave intensity in 2D sensing systems and, in general, for any application requiring simultaneously high speed and high sensitivity EM detection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.