| 摘要 |
PURPOSE:To enable the captioned ion beam to be radiated correctly at the fixed position on an object, by providing a control power source which varies the current value of the ion beam and a means which gives the ion beam the deflecting action of the direction and the angle which correspond to the control signals coming from this control power source. CONSTITUTION:A voltage applied between an emitter 6 and a controlling electrode 7 is converted to its digital signals by an AD converting circuit 17 and is input into data reading circuits 20, 21 which are installed on the earth side by means of interfaces 18, 19 where a phototcoupler is used. Data read circuits 20, 21 are respectively provided with a memory circuit (programmable read-only memory) (PROM) and the digital signals corresponding to signals which are input and read out, their values are converted into the analog signals by DA converting circuits 22, 23, thereafter said values are fed into two deflection signal amplifiers connected to deflecting electrodes 26, 27 which perfrom the deflection of X-direction and Y-direction. By doing this, the irradiated position of the object of ion beam can be kept constant. |
