CRT magnetic field compensation
US4864192A · kind A · utility
9Cited by
5References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 9, 1987 |
| Grant date | Sep 5, 1989 |
| Priority date | — |
| Expiry date | Nov 9, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/003
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
As CRT display is housed in a magnetic shield to reduce the image distortions caused by the external magnetic field produced by an NMR scanner. To further improve image quality, three sets of compensating coils are positioned around the CRT display and inside the shield to produce magnetic fields which offset the effects of the residual external magnetic field components that penetrate the shield or enter through the window in the shield used to view the CRT screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.