Method and system to enhance dynamic range conversion useable with CMOS three-dimensional imaging
US6678039B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 23, 2002 |
| Grant date | Jan 13, 2004 |
| Priority date | — |
| Expiry date | May 23, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S17/894
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
High dynamic range brightness information is acquired by inputting detection current to a high (adjustable) gain resettable integrator whose output V(t) is compared to a Vth threshold by a comparator whose output is counted by a reset counter as V(t)≧Vth. When a desired count is attained, data acquisition ends, the counter is read, and the entire circuit is reset. A TOF data acquisition circuit includes first and second sequences of series-coupled delay units, and a like number of latch units coupled between respective delay units. A phase discriminator compares output from each chain and feedback a signal to one of the chains and to a comparator and can equalize delay through each chain. A control voltage is coupled to the remaining chain to affect through-propagation delay time. The latch units can capture the precise time when V(t)≧Vth. Successive measurement approximation can enhance TOF resolution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.