| 摘要 |
PURPOSE:To attain high-precision deflection by controlling the voltage of a voltage source by the signal from a detection coil coupling electromagnetically with a deflecting coil. CONSTITUTION:Signals from magnetic-field detection coil 1' coupling electromagnetically with deflecting coil 1 are fed back to power amplifier 3', where they are compared with DC voltage 6'' at its input terminal and then amplified, thereby driving coil 1. Further, switch signal 6' turns transistor 7 ON at a scanning time, and OFF at a flyback time; at the scanning, a current obttained by integrating the output of amplifier 3' flows to coil 1 so as to make the deflecting current increase linearly, so that the variation in the current will be detected as the DC voltege of coil 1'. |
