| 摘要 |
PURPOSE:To enable a highly efficient light-emitting electron tube which is very compact and in which optical controlling or the control of an emission output from the electron tube can be performed by enabling the temperature of a thermionic emission cathode to be controlled from the outside. CONSTITUTION:In an outer tube 1 airtightly formed by transparent glass, a pair of cathodes 2 and 3 and an anode 4 are installed. The anode 4 is installed almost in the middle between the cathodes 2 and 3 and has mesh- or grid-like form. From a d.c. power source 7, positive d.c. voltages are respectively applied across the anode 4 and the cathode 2 and across the anode 4 and the cathode 3 through a resistance 6. The amplitudes of the above d.c. voltages are adjusted so that thermions emitted from the cathode 2 are accelerated and formed into a beam-like shape before reaching the anode 4. The thermions of the beam-like shape, after passing through the anode 4, are decelerated so that their speed becomes zero immediately before reaching the cathode 3. The discharge output can be easily changed by controlling the temperature of a heater 9 by an external means such as a d.c. variable power source 10 or an a.c. variable power source 11. |
