Abstract: In an electron beam exposure method in which an article subjected to exposure and an electron beam irradiation spot are moved relative to each other at a continuous speed, the article is exposed at a plurality of irradiation intensities of an electron beam by changing a transmittance of an electron optical system for forming the electron beam irradiation spot on the article.

Abstract: An exposure apparatus of an optical disk master having a laser source, a deflector for deflecting a recording laser beam obtained based on the laser beam of the laser source and an objective lens for focusing the recording laser beam on an optical disk master, has a lens system provided between the laser source and the deflector, which has a first lens for focusing the laser beam and a second lens for adjusting the focused laser beam to a desired beam diameter; and a pinhole placed at a practical focal position of the lens system.

Abstract: Pits are exposed and formed on a resist master disc by an electron beam recorder. A leading end and a trailing end of each pit are substantially the same form. The electron beam recorder includes: an electron beam source that discharges electron beams; a voltage controller that generates voltages based on a predetermined information signals; control electrodes that deflect the electron beams based on the voltages; a shield plate having a passing position to pass the electron beams and a shielding position to shield the electron beams; and a turntable that carries and rotates the disc. The voltage controller controls the voltages applied to the control electrodes to substantially equalize a first velocity of the electron beams to travel from a first shielding position to the passing position with a second velocity of the electron beams to travel from the passing position to a second shielding position.

Abstract: An electron beam recorder includes an electron optical system for irradiating the electron beam on a master of an information recording medium and a shielding plate for shielding the electron beam. An electron beam irradiation quantity detector is provided on the shielding plate and is divided into first and second electron beam detecting portions along an information recording direction on the master. A difference detector calculates a difference between 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 such that a position of the electron beam in a direction substantially perpendicular to the information recording direction is detected from the difference.

Abstract: A method for exposing an optical disk master includes rotating a substrate disk coated with a photoresist, focusing a beam on the photoresist for exposure through an objective lens, and exposing the photoresist so as to form tracks on the substrate disk in its circumferential direction. At this time, the beam is deflected at least temporarily by passing through a deflector. The beam is divided into a first beam and a second beam after passing through the deflector, and the first beam is focused on the photoresist. A difference between the current position and the target position of an optical path of the second beam is detected, and the deflection operation of the deflector is corrected based on the difference so that the optical path of the second beam is located at the target position. This method can improve the track pitch accuracy of an optical disk having a narrow track pitch.

Abstract: An exposure apparatus of an optical disk master having a laser source, a deflector for deflecting a recording laser beam obtained based on the laser beam of the laser source and an objective lens for focusing the recording laser beam on an optical disk master, has a lens system provided between the laser source and the deflector, which has a first lens for focusing the laser beam and a second lens for adjusting the focused laser beam to a desired beam diameter; and a pinhole placed at a practical focal position of the lens system.

Abstract: The width and/or depth of guide grooves on the disc substrate surface are changed in each data recording layer and the guide groove depth of the recording film layer is appropriately shaped in each data recording layer to provide a high density, high recording capacity optical disc. The optical disc has plural substrate layers each having plural guide grooves; plural data recording layers laminated on the substrate layers, each of the plural data recording layers having a recording film for recording data over the guide grooves; and an intermediate layer between the plural data recording layers. The guide groove width is different on each substrate layer. The guide grooves of the data recording layers formed according to the guide grooves of the substrate layer have the same pitch in each data recording layer.

Abstract: A method for manufacturing an optical disk master includes: forming a resist layer by the application of a chemically amplified resist; converting an information signal into a multipulse signal having a symmetrical shape; exposing the resist layer in accordance with the multipulse signal; heat-treating the resist layer; and developing the resist layer to form signal pits. The signal pits are exposed to the multipulse signal, which is obtained by dividing a pulse into symmetrical pulses, thereby adjusting the exposure area and achieving a desired pit shape.

Abstract: An exposure apparatus of an optical disk master having a laser source, a deflector for deflecting a recording laser beam obtained based on the laser beam of the laser source and an objective lens for focusing the recording laser beam on an optical disk master, has a lens system provided between the laser source and the deflector, which has a first lens for focusing the laser beam and a second lens for adjusting the focused laser beam to a desired beam diameter; and a pinhole placed at a practical focal position of the lens system.

Abstract: The width and/or depth of guide grooves on the disc substrate surface are changed in each data recording layer and the guide groove depth of the recording film layer is appropriately shaped in each data recording layer to provide a high density, high recording capacity optical disc. The optical disc has plural substrate layers each having plural guide grooves; plural data recording layers laminated on the substrate layers, each of the plural data recording layers having a recording film for recording data over the guide grooves; and an intermediate layer between the plural data recording layers. The guide groove width is different on each substrate layer. The guide grooves of the data recording layers formed according to the guide grooves of the substrate layer have the same pitch in each data recording layer.

Abstract: An electron beam recorder includes an electron optical system for irradiating an electron beam on a master of an information recording medium and an electron beam irradiation position detecting unit for detecting an irradiation position of the electron beam in the electron optical system while the electron beam is being irradiated on the master by the electron optical system.

Abstract: The width and/or depth of guide grooves on the disc substrate surface are changed in each data recording layer and the guide groove depth of the recording film layer is appropriately shaped in each data recording layer to provide a high density, high recording capacity optical disc. The optical disc has plural substrate layers each having plural guide grooves; plural data recording layers laminated on the substrate layers, each of the plural data recording layers having a recording film for recording data over the guide grooves; and an intermediate layer between the plural data recording layers. The guide groove width is different on each substrate layer. The guide grooves of the data recording layers formed according to the guide grooves of the substrate layer have the same pitch in each data recording layer.

Abstract: A displacement detection method in which by reflecting a light beam on a surface of an object to be measured, a displacement of the surface of the object is detected from a change of the reflected light beam due to a change of the displacement of the surface of the object, includes the steps of: causing light beams to be incident upon a substantially identical position on the surface of the object from at least two light sources confronting each other substantially; detecting by position detectors directional changes of the light beams reflected on the surface of the object, respectively; normalizing output signals of the position detectors by luminous intensities received by the position detectors, respectively; and calculating a sum or a difference of the normalized output signals of the position detectors.

Abstract: The width and/or depth of guide grooves on the disc substrate surface are changed in each data recording layer and the guide groove depth of the recording film layer is appropriately shaped in each data recording layer to provide a high density, high recording capacity optical disc. The optical disc has plural substrate layers each having plural guide grooves; plural data recording layers laminated on the substrate layers, each of the plural data recording layers having a recording film for recording data over the guide grooves; and an intermediate layer between the plural data recording layers. The guide groove width is different on each substrate layer. The guide grooves of the data recording layers formed according to the guide grooves of the substrate layer have the same pitch in each data recording layer.

Abstract: A method for exposing an optical disk master includes rotating a substrate disk coated with a photoresist, focusing a beam on the photoresist for exposure through an objective lens, and exposing the photoresist so as to form tracks on the substrate disk in its circumferential direction. At this time, the beam is deflected at least temporarily by passing through a deflector. The beam is divided into a first beam and a second beam after passing through the deflector, and the first beam is focused on the photoresist. A difference between the current position and the target position of an optical path of the second beam is detected, and the deflection operation of the deflector is corrected based on the difference so that the optical path of the second beam is located at the target position. This method can improve the track pitch accuracy of an optical disk having a narrow track pitch.

Abstract: An exposure apparatus of an optical disk master having a laser source, a deflector for deflecting a recording laser beam obtained based on the laser beam of the laser source and an objective lens for focusing the recording laser beam on an optical disk master, has

Abstract: Pits are exposed and formed on a resist master disc by an electron beam recorder. A leading end and a trailing end of each pit are substantially the same form. The electron beam recorder includes: an electron beam source that discharges electron beams; a voltage controller that generates voltages based on a predetermined information signals; control electrodes that deflect the electron beams based on the voltages; a shield plate having a passing position to pass the electron beams and a shielding position to shield the electron beams; and a turntable that carries and rotates the disc. The voltage controller controls the voltages applied to the control electrodes to substantially equalize a first velocity of the electron beams to travel from a first shielding position to the passing position with a second velocity of the electron beams to travel from the passing position to a second shielding position.

Abstract: The width and/or depth of guide grooves on the disc substrate surface are changed in each data recording layer and the guide groove depth of the recording film layer is appropriately shaped in each data recording layer to provide a high density, high recording capacity optical disc. The optical disc has plural substrate layers each having plural guide grooves; plural data recording layers laminated on the substrate layers, each of the plural data recording layers having a recording film for recording data over the guide grooves; and an intermediate layer between the plural data recording layers. The guide groove width is different on each substrate layer. The guide grooves of the data recording layers formed according to the guide grooves of the substrate layer have the same pitch in each data recording layer.