| 摘要 |
PURPOSE:To control the amount of exposure without changing the conditions of an electron gun, by applying a high frequency voltage on an electron beam deflection device, vibrating the electron beam at a right angle, passing the beam through a screening plate having an opening, and controlling the pulse width of the pulse shaped beam. CONSTITUTION:The high frequency voltage is applied on the reflecting plates 11 of the electron beam exposing apparatus, and the high frequency alternating field is formed. The electron beam 2 is deflected by the electric field and vibrate as shown by an arrow 16. The electron beam 2 passes through a screening plate 14 when the beam moves from A to B. When the electron beam exceeds B, it is screened by the screening plate 14, and is not sent out. This state continues until the beam moves from B to C and B again. The electron beam passes the opening 17 when it moves from B to A and to D. The beam is not sent out when it moves from D to E and D again. In this method, the electron beam is transformed into a pulse shaped beam, and the amount of exposure can be readily and precisely controlled without changing the conditions of the electron gun. |
