| 摘要 |
PURPOSE:To dim and to achieve the matrix driving by providing a control grid between a thermoionic cathode and an anode electrode, and controlling a current flowing between the thermoionic cathode and the anode electrode. CONSTITUTION:An anode electrode 2 and a thermoionic cathode 3 are provided within a glass bulb 1, and a control grid 6 is installed between the electrode 2 and the cathode 3. Further, a fluorescent film 4 is provided in the spherical surface of the glass bulb 1, and mercury, for example, is filled and sealed in the space within the glass bulb 1. A waveform which is obtained by rectifying an alternating voltage in full-wave is applied between the electrode 2 and the cathode 3 of a hot cathode discharging type lamp having such a structure, and when a trigger pulse is applied between the grid 6 and the cathode 3 the discharging is started, and when the phase of the trigger pulse is changed corresponding to the rectified waveform, it is possible to adjust the volume of luminescence on average. The driving of the grid 6 is made with very small electric power, and since it is possible to make a transistor for driving small, it is possible to make the control of luminescence in a matrix state. |
