Method and apparatus for removing foreign matters from a cathode-ray tube
US5403989A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1993 |
| Grant date | Apr 4, 1995 |
| Priority date | — |
| Expiry date | Mar 24, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/82
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a color cathode-ray tube, only a foreign matter adhering to a shadow mask is removed effectively without thermal deformation of the shadow mask or thermal denaturation of phosphors. An electron beam produced by an electron gun incorporated in a cathode-ray tube itself is scanned or irradiated to all over a shadow mask of the color cathode-ray tube. The radiant state of a fluorescent screen at this stage is checked to detect a foreign matter adhering to the shadow mask. The electron beam is deflected to align with the position at which the foreign matter is detected, and then irradiated to the foreign matter in the form of pulses. Thus, the foreign matter is heated and removed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.