Modular display apparatus with means for preventing brightness variations
US4525653A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 6, 1983 |
| Grant date | Jun 25, 1985 |
| Priority date | — |
| Expiry date | Sep 6, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J31/126
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A display apparatus including a modular type display tube having a cathodoluminescent screen, elongate thermionic or P-N electron emitters, a channel plate electron multiplier and an apertured control plate between the emitters and the multiplier. The control plate has a plurality of switching electrodes on the side facing the emitter and a set of brightness electrodes on the opposite side and extending transversely to the switching electrodes. In order to compensate for variations in emission from the emitters, the brightness voltage to the brightness electrodes is turned-off and emission variations are measured by scanning using the switching electrodes. Correction voltages are computed and applied together with the modulation signal in synchronism with the scanning of the switching electrodes. An apertured shielding plate is provided to prevent the switching voltages at the switching electrodes from affecting the emissions from the emitters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.