| 摘要 |
<p>PURPOSE:To obtain an electron gun of a high luminance obtained by effectively applying capabilities of a single crystal, by specifying the axial orientation, the circular-cone angle of the tip and the bias voltage of a hot cathode, made up with a single crystal having a crystal structure similar to that of calcium hexaboride. CONSTITUTION:A single crystal having a crystal structure similar to that of calcium hexaboride, such as LaB6, is used for a hot cathode. The axial orientation of the hot cathode is made to coincide with [013], [012], [023], or equivalent to any one of these three, and the circular-cone angle of the tip of the hot cathode is set within the range of 100-180 deg.. Besides, the bias voltage is made to be adjustable so that a high luminance can be obtained within the cathode temperature range of 1,400-1,550 deg.C. Through the means mentioned above, an electron gun can be obtained. Where abilities of the single crystal is efficiently utilized a high luminance is provided.</p> |
