Apparatus for adjusting a focal position of an electron beam and electron beam projection apparatus including the same
AssigneeFujitsu Limited
InventorsYoshihisa Oae, Akio Yamada, Hiroshi Yasuda
Life of this patent
Estimating the term…
Abstract
An electron beam projection apparatus providing a magnetic refocusing lens for adjusting a focal position of an electron beam on an object. An axis of an auxiliary magnetic field produced by the magnetic refocusing lens is required equivalently to agree to that of a convergent magnetic field produced by a magnetic object lens. An inclination adjustment apparatus of the magnetic refocusing lens provides a rolling mechanism being independently rotatable on two axes being perpendicular to each other and also perpendicular to a direction of an axis of a convergent magnetic field. With this inclination adjustment apparatus, adjustment operation is improved.
Claims6
An apparatus for adjusting a focal position of an electron beam converged by a magnetic object lens:
- comprising
- an auxiliary magnetic lens arranged in a magnetic field produced by said magnetic object lens, said auxiliary magnetic lens producing an auxiliary magnetic field over said magnetic field produced by said magnetic object lens, and an intensity of said auxiliary magnetic field being changeable;
- inclination adjusting means for changing said auxiliary magnetic lens opposite to said magnetic object lens;
- and
- said inclination adjusting means including a rotation mechanism being independently rotatable on two axes which are perpendicular to each other and each of which is also perpendicular to a direction of an axis of a convergent magnetic field produced by said magnetic object lens.
Dependencies are inferred from the claim text.