Purity/beam landing error measurement method for electronic display devices
US6097355A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 1997 |
| Grant date | Aug 1, 2000 |
| Priority date | — |
| Expiry date | Nov 17, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J9/42
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of calculating beam landing errors in an electronic display device having color phosphor elements and electron guns to generate electron beams to impinge on corresponding phosphor elements require a magnetic field to be generated to deflect an electron beam relative to the corresponding phosphor element on which the electron beam is to impinge. The intensity of light emitted by the phosphor elements in the measurement area is measured as the electron beam impinges thereon. The polarity of the magnetic field is reversed and the above step is repeated. Thereafter, the magnitude of the magnetic field is changed and the above two steps are repeated thereby to measure at least two different light intensities resulting from electron beam influenced by each polarity magnetic field. The at least two different light intensities resulting from electron beams influenced by each polarity magnetic field are then approximated with straight lines and an intersection point of the straight lines is determined. A corresponding magnetic field to the intersection point is also determined. A magnetic field is then generated corresponding to the intersection point and the intensity of light emi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.