Room temperature, low-light-level visible imager
US6476374B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2000 |
| Grant date | Nov 5, 2002 |
| Priority date | — |
| Expiry date | Apr 25, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/802
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A photodetector sensitive to visible and shorter wavelengths is capable of single photon sensitivity at room temperatures and video frame rates. It includes (a) a compound semiconductor photodiode, biased below its avalanche breakdown threshold, comprising III-V elemental components and having a bandgap with transition energy higher than the energy of infrared photons; and (b) a high trans-impedance interface circuit, arranged to receive a signal from the photodiode junction and to amplify said signal. Preferably, the photodiode junction is integrated in a first microstructure on a first substrate, and its interface circuit in a second microstructure on a second substrate. Both microstructures are then joined in a laminar, sandwich-like structure and communicate via electrically conducting contacts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.