Electron beam recorder, electron beam irradiation position detecting method and electron beam irradiation position controlling method

A method of detecting an irradiation position of an electron beam in an electron beam recorder including an electron optical system for irradiating the electron beam on a master of an information recording medium, a shielding deflector for deflecting the electron beam for its shielding, a shielding plate for shielding the electron beam deflected by the shielding deflector and an electron beam irradiation quantity detector provided on the shielding plate and divided into first and second electron beam detecting portions along an information recording direction on the master, the method comprising the steps of:

• irradiating the electron beam on the master;
• deflecting the electron beam by the shielding deflector;
• shielding by the shielding plate the electron beam deflected by the shielding deflector;
• detecting a first quantity of the electron beam irradiated on the first electron beam detecting portion and a second quantity of the electron beam irradiated on the second electron beam detecting portion;
• obtaining a difference between the first quantity and the second quantity;
• and
• determining from the difference a position of the electron beam in a direction substantially perpendicular to the information recording direction.

A method of controlling an irradiation position of an electron beam in an electron beam recorder including an electron optical system for irradiating the electron beam on a master of an information recording medium, a shielding deflector for deflecting the electron beam for its shielding, an irradiation position correcting deflector for deflecting the electron beam for its irradiation position correction in a direction substantially perpendicular to an information recording direction on the master, a shielding plate for shielding the electron beam deflected by the shielding deflector and an electron beam irradiation quantity detector provided on the shielding plate and divided into first and second electron beam detecting portions along the information recording direction, the method comprising the steps of:

• irradiating the electron beam on the master;
• deflecting the electron beam by the shielding deflector;
• shielding by the shielding plate the electron beam deflected by the shielding deflector;
• detecting a first quantity of the electron beam irradiated on the first electron beam detecting portion and a second quantity of the electron beam irradiated on the second electron beam detecting portion;
• obtaining a difference between the first quantity and the second quantity;
• determining from the difference a position of the electron beam in the direction substantially perpendicular to the information recording direction;
• producing an irradiation position correcting signal on the basis of the position of the electron beam;
• and
• inputting the irradiation position correcting signal to the irradiation position correcting deflector so as to deflect the electron beam in accordance with the irradiation position correcting signal by the irradiation position correcting deflector in the direction substantially perpendicular to the information recording direction.