| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an indirectly heated cathode body structure improved in heat efficiency and capable of further reducing power consumption in heating a heater 4 only by slightly altering the structure. SOLUTION: This indirectly heated cathode body structure is equipped with a cathode sleeve 1 made of a high-melting point metal, a metallic cup 2 made of a high-melting point metal and fitted to the cathode sleeve 1 so as to seal it up, an electron-emitting cathode substrate 3 packed in the metallic cup 2 and impregnated with a compound mainly composed of a plurality of alkaline earth metal oxides including barium(Ba), a heater 4 built in the cathode sleeve 1, a funnel-shaped metallic support body 5 with its smaller diameter part 5S supporting the other end area of the cathode sleeve 1 inserted therein and with its larger diameter part 5L concentrically covering one end side of the cathode sleeve 1, and a cylindrical metallic reflector 6 with one end area thereof supporting the larger diameter part 5L of the funnel-shaped metallic support 5 inserted therein and with the other end area thereof extending beyond the other end area of the cathode sleeve 1.</p> |
