Ultra-high dynamic range two photodiode pixel architecture
US9933300B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 2016 |
| Grant date | Apr 3, 2018 |
| Priority date | — |
| Expiry date | Jul 1, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/802
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A pixel comprises a high-response photodiode that collects photocharge, a first transfer gate that enables the charge to be transferred off the high-response photodiode, completely emptying it onto a low-response photodiode, a second transfer gate enables the charge to be transferred off the low-response photodiode, completely emptying it onto floating diffusion, a third transfer gate for anti-blooming; the floating diffusion collects the transferred charge creating a change of voltage, a means of resetting the floating diffusion. A source-follower is modulated by the voltage on floating diffusion to control bit-line voltage and column-amplifier output. In examples, photocharge is integrated onto both the high-response photodiode and onto the low-response photodiode. The column readout circuit consists of a column amplifier that uses capacitors to set the amplifier gain, three sampling capacitors used as analog memory and for correlated double sampling, and a comparator that assists in providing the final output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.