Cathodoluminiscent lighting system

摘要

Electron sources for a cathodoluminescent lighting system are disclosed. An electron source is a broad-beam reflecting-type electron gun (243) having a cathode (240) for emitting electrons and a reflector and/or secondary emitter electrode and no grids. An alternative electron gun has a cathode having a heater welded to a disk, the disk having an emissive surface on a side facing a dome-shaped defocusing grid and an anode. A lighting system (100) incorporating the electron sources has an envelope (250) with a transparent face (252), an anode (242) with a phosphor layer (254) to emit light through the face and a conductor layer. The system also has a power supply (102, 104, 105, 106, 108) for providing from five to thirty thousand volts of power to the light emitting device to draw electrons from cathode to anode and excite a cathodoluminescent phosphor, and the electrons transiting from cathode to anode are essentially unfocused. A power-factor-corrected embodiment is also disclosed.