Analog-digital converter with variable threshold levels
US4064484A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 1976 |
| Grant date | Dec 20, 1977 |
| Priority date | — |
| Expiry date | Jul 26, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T1/0007
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An analog-digital converter comprises a comparator to which signals to be converted are applied, and a threshold circuit coupled with the comparator in order to control the threshold level of the comparator, so that the signals applied to the comparator are converted into binary signals based upon a predetermined threshold level. The threshold level corresponding to the output of the threshold circuit is compensated in accordance with the variations in the levels of the signals applied to the comparator. The threshold level of the comparator is changed to a compensated level when the result, calculated from the average level of the signals approximately corresponding to a predetermined area in a field of the object and that of the signals approximately corresponding to plural areas which are in the vicinity of the predetermined area, is different from that of the preceding frame.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.