| 摘要 |
<p>ELIMINATION OF LANDING ERRORS IN ELECTRON-OPTICAL SYSTEM OF MIXED FIELD TYPE In an el ectron-optical system of the mixed field type in which magnetic and electric fields are respectively operative to project a focused image of an object of the system upon a target structure and to simultaneously scan such image across the target structure, beam landing errors are eliminated by dimensioning and locating the solenoid for generating the magnetic field and the electrostatic yoke for generating the electric field so that the landing errors due to non-uniformity of the electric field, for example, by reason of field-free regions at the opposite ends thereof, are substantially cancelled by landing errors due to non-uniformity of the magnetic field, for example, as constituted by flare field regions at the opposite ends of the magnetic field.</p> |
