| 摘要 |
PROBLEM TO BE SOLVED: To provide a cathode-ray tube capable of generating uniform and constant beam current for a long time and being manufactured reproducibly. SOLUTION: This cathode-ray tube has at least one oxide cathode having a cathode support body having a cathode film made of electron emitting material containing a cathode base made of cathode metal and an oxide particle. The oxide particle contains alkaline earth oxide selected from a group comprising oxides of calcium, strontium, and barium. As the alkaline earth oxide, an oxide selected from a group comprising oxides of scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium is doped in a range from 120 ppm to 500 ppm at maximum. The electron emitting material has a conductance from 3*10-3 Ω-1cm-1 to 12.5*10-3 Ω-1cm-1. |
