METHOD AND APPARATUS FOR ELECTRON BEAM IRRADIATION

摘要

A method and apparatus (11) for irradiating an electron beam, wherein a triangular wave generator (22) provides a triangular wave current to a scanning coil (17) to move the electron beam in a first scanning direction (Y); while a square wave generator (21) provides a square wave current to a deflecting coil (16) to move the electron beam in a second scanning direction (X) orthogonal to the first scanning direction (Y). The triangular wave current provided from the triangular wave generator is modulated to cancel the effects of hysteresis in the scanning coil. Further, the rise of the square wave current is synchronized and shifted a prescribed interval in relation to the peak values of the triangular wave current in order to distribute the reversing points on the electron beam path along the second scanning direction.