Master disc manufacturing apparatus

An apparatus for manufacturing a master by irradiation of an electron beam on a substrate, comprising:

• an electron-beam emitting section for emitting said electron beam;
• a deflection drive section for performing deflection control on said electron beam;
• a rotation drive section for rotating said substrate;
• a movement drive section for relatively moving said electron-beam emitting section and said substrate in a predetermined direction in a plane parallel to a principal surface of said substrate;
• a distance measuring section for measuring an displacement amount of said substrate in said predetermined direction when said substrate is rotated;
• an asynchronous-component generating section for calculating a weighted mean value of a current displacement amount measured by said distance measuring section and an accumulated displacement amount and for subtracting the calculated weighted mean value from the measured current displacement amount to generate an asynchronous component, said accumulated displacement amount being a previous weighted mean value for one rotation of said substrate;
• and
• a control section for controlling said deflection drive section based on a magnitude of said asynchronous component to thereby adjust an irradiation position of said electron beam.