Magneto-optic image scanning detector
US4574312A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 5, 1982 |
| Grant date | Mar 4, 1986 |
| Priority date | — |
| Expiry date | May 5, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved magneto-optic image scanning detector for placement in a light beam between an image and a light detector generating an electrical signal as a function of the intensity of light impinging thereof. The signal-to-noise ratio is increased by mounting two chips of identical configuration in adjacent aligned relationship and scanning them in patterns whereby the light-blocking effect of non-selected areas is increased. Additionally, logic is provided in the driving circuit to alternate the current direction within the selected area to open and close each selected area during its portion of the scan pattern at a predetermined rate whereby the light beam passing therethrough is pulsated. A discriminator is added in line with the electric signal generated by the detector to produce an output as a function only of the pulsating portion whereby the d.c. background light is eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.