| 摘要 |
PURPOSE:To properly control the amount of a getter member scattered by measuring the amount of light transmitted by a getter member film adhering to the inner surface of the bulb during flashing of the getter member and controlling a power supply for dielectrically heating the getter member in accordance with the signal produced as the result of the measurement. CONSTITUTION:A ring-like case 12 containing a getter member 13 is installed in the neck 4 of the bulb 1 of a cathode-ray tube. The getter member 13 is flashed by a dielectric heating coil 15 installed outside the neck 4 to increase the vacuum degree of the internal atmosphere of the bulb 1. Here, a laser light source 16 and a light-receiving element 17 such as a phototransistor are installed outside the neck 4 and between an electron gun 8 and a getter case 12 so as to control dielectric heating by measuring the amount of light transmitted by a getter member film adhering to the inner surface of the bulb. As a result, it is possible to achieve improved quality by enabling accurate control since getter flash is controlled by directly measuring the amount of getter scattered. |
