| 摘要 |
PURPOSE:To make the peak of beam strength findable in a speedy manner without any scanning of an analytic magnetic field so as to aim at the promptitude of regulation, by installing a coule of electrostatic deflecting plates in an interspace between an analyzer magnet and an nalyzer slit. CONSTITUTION:During beam lining, a couple of electrostatic deflecting plates 5 are installed in an interspace between an analyzer magnet 2 and a slit 3 while an AC signal from an oscillator 6 is impressed on these plates 5 and thereby an ion beam 1 is slightly oscillated in the same inner surface as being deflected by the analyzer magnet 2. At this time, the value of a current flowing into a target 4 is phase-detected by a phase wave detector 7 by regarding the AC signal from the oscillator 6 as a reference signal whereby, before the AC signal is impressed on these deflecting plates 5, that is, when the ion beam 1 is not yet deflected by these deflecting plates 5, an error signal (e) proportioned to a positional slippage in the beam 1 in relation to the central part of the slit 3 is secured at an output port 8. Using this error signal (e), an analyzer magnet power source 9 is conducted with negative feedback whereby an analytic magnetic field is minutely regulated so as to get the peak value of a beam current. |
