Abstract: It is an object of the present invention to make it possible to stably and correctly measure a changing amount of a beam position when a beam displacement is measured prior to a recording operation performed by an electron beam recording apparatus. A measuring device for measuring a displacement of an electron beam prior to a recording operation, comprises: a knife edge disposed at an irradiating position of the beam spot; detecting means (Farady cup or the like) for detecting an electron beam irradiating through the knife edge; filter means (high frequency cut filter or the like) for removing a changing frequency component of measurement subject from an output of the detecting means; and control means for controlling a reference position of the electron beam in accordance with an output from the filter means, in a manner such that the center of the beam spot will be at the front end position of the knife edge.

Abstract: To provide a new recording method and recording apparatus with respect to an optical recording medium, the recording method and recording apparatus being able to deal with a high density of an optical recording medium of recent years. Recording of a recording track and a prepit is carried out by sequentially deflecting a single beam.

Abstract: To provide a new recording method and recording apparatus with respect to an optical recording medium, the recording method and recording apparatus being able to deal with a high density of an optical recording medium of recent years. Recording of a recording track and a prepit is carried out by sequentially deflecting a single beam.

Abstract: An original master manufacturing method of rotating an original master at a constant linear velocity, moving in a plane the original master in a predetermined radial direction at a constant velocity which is provided with a predetermined amount of movement per round of the original master, deflecting the electron beam in the planar movement direction of the original master by a first deflection amount equal to the predetermined movement amount per round of the original master on the surface of the original master during exposure of the concentric circular data patterns corresponding to first through (n?1)-th rounds of each of the plurality of tracks, upon completion of the exposure of the concentric circular data patterns corresponding to the first through (n-1)-th rounds, deflecting the electron beam in a direction opposite to the planar movement direction of the original master by a second deflection amount equal to the predetermined distance on the surface of the original master, and upon completion of exp

Abstract: An apparatus includes a beam deflection portion for deflecting the electron beam to change an irradiation position of the electron beam; a synchronization signal generation portion for generating a synchronization signal which is in synchronization with the rotation of the substrate; a controller for controlling the beam deflection portion on the basis of the synchronization signal in order to deflect the electron beam in a rotational radial direction of the substrate and in a rotational tangential direction of the substrate opposite to a rotational direction of the substrate, while drawing transition is performed from one circle to another circle; and a beam cutoff portion for cutting off the irradiation of the electron beam on the substrate, for a period during the electron beam is deflected in the rotational radial direction.

Abstract: A beam adjusting sample having a flat surface being like a plate and having two edges orthogonal to each other is employed. A beam is applied to the beam adjusting sample to detect an amount of the beam passing through the beam adjusting sample. The beam vertically scans the two edges.

Abstract: It is an object of the present invention to make it possible to stably and correctly measure a changing amount of a beam position when a beam displacement is measured prior to a recording operation performed by an electron beam recording apparatus. A measuring device for measuring a displacement of an electron beam prior to a recording operation, comprises: a knife edge disposed at an irradiating position of the beam spot; detecting means (Farady cup or the like) for detecting an electron beam irradiating through the knife edge; filter means (high frequency cut filter or the like) for removing a changing frequency component of measurement subject from an output of the detecting means; and control means for controlling a reference position of the electron beam in accordance with an output from the filter means, in a manner such that the center of the beam spot will be at the front end position of the knife edge.

Abstract: To provide a new recording method and recording apparatus with respect to an optical recording medium, the recording method and recording apparatus being able to deal with a high density of an optical recording medium of recent years. Recording of a recording track and a prepit is carried out by sequentially deflecting a single beam.

Abstract: An apparatus includes a beam deflection portion for deflecting the electron beam to change an irradiation position of the electron beam; a synchronization signal generation portion for generating a synchronization signal which is in synchronization with the rotation of the substrate; a controller for controlling the beam deflection portion on the basis of the synchronization signal in order to deflect the electron beam in a rotational radial direction of the substrate and in a rotational tangential direction of the substrate opposite to a rotational direction of the substrate, while drawing transition is performed from one circle to another circle; and a beam cutoff portion for cutting off the irradiation of the electron beam on the substrate, for a period during the electron beam is deflected in the rotational radial direction.

Abstract: An optical disk 11 (sample) is laid on a sample moving unit 21 within a vacuum chamber 20. An electron beam radiating mechanism 30 radiates an electron beam to the optical disk 11 while moving the optical disk 11 at a constant speed. Electron detecting means 27 detects an electron from the optical disk 11. Thus, the track pitch is measured on the basis of a detected electron signal and a measured movement amount of the optical disk 11. Also, the electron beam radiating mechanism 30 is provided with a fast deflector 33 for averaging within a deflection area to measure the track pitch.

Abstract: Preceding to the reading out of the recording information of the optical disk by the pick-up, the height of the foreign material existing at the light converging position on the information reading surface is detected by the detector, and when the height of the foreign material is higher than the floating height h of the SIL, the magnetic field is generated by applying the control current corresponding to the height of the foreign material to the coil as the magnetic field generator at the timing before the foreign material is moved to the information reading position of the pick-up by the rotation of the optical disk. Then, when the magnetic field is provided to the magnetic substance fixedly holding the SIL which is floating, the movement operation to separate the SIL to the higher position than the height of the foreign material from the information reading surface together with the magnetic substance, is conducted.

Abstract: A laser-based measuring apparatus divides a light beam from a laser light source into at least two light beams, passes the light beams through different optical paths from each other, recombines the light beams, has the light beams interfere with each other to generate interfered light, opto-electrically transduces the interfered light to an optical frequency, and measures the amount of travel of an object which changes an optical path length of a portion of an optical path based on the optical frequency. The measuring apparatus has a portion for generating at least two measuring light beams from the laser light source, two reflection planes included in an object moving on a measuring axis, arranged back-to-back to each other on the measuring axis, and an opposing incident optical system for directing the measuring light beams into the reflection planes, respectively, such that the measuring light beams oppose to each other on the measuring axis.

Abstract: A beam adjusting sample having a flat surface being like a plate and having two edges orthogonal to each other is employed. A beam is applied to the beam adjusting sample to detect an amount of the beam passing through the beam adjusting sample. The beam vertically scans the two edges.

Abstract: An optical disk 11 (sample) is laid on a sample moving unit 21 within a vacuum chamber 20. An electron beam radiating mechanism 30 radiates an electron beam to the optical disk 11 while moving the optical disk 11 at a constant speed. Electron detecting means 27 detects an electron from the optical disk 11. Thus, the track pitch is measured on the basis of a detected electron signal and a measured movement amount of the optical disk 11. Also, the electron beam radiating mechanism 30 is provided with a fast deflector 33 for averaging within a deflection area to measure the track pitch.

Abstract: A laser-based measuring apparatus divides a light beam from a laser light source into at least two light beams, passes the light beams through different optical paths from each other, recombines the light beams, has the light beams interfere with each other to generate interfered light, opto-electrically transduces the interfered light to an optical frequency, and measures the amount of travel of an object which changes an optical path length of a portion of an optical path based on the optical frequency. The measuring apparatus has a portion for generating at least two measuring light beams from the laser light source, two reflection planes included in an object moving on a measuring axis, arranged back-to-back to each other on the measuring axis, and an opposing incident optical system for directing the measuring light beams into the reflection planes, respectively, such that the measuring light beams oppose to each other on the measuring axis.

Abstract: A recording apparatus of a master disc of optical discs which can irradiate a recording beam to a preferable position on the master disc even when a vibration occurs in a rotary shaft to hold the master disc or when a rotational fluctuation occurs in a spindle motor. An angle position in the rotating direction of the rotary shaft and a displacement of the rotary shaft in a radial direction of the master disc are detected. Based on the angle position and the displacement, the present deviation at the present angle position from the reference position of the rotary shaft is calculated. Based on the present deviation, the irradiating spot position is adjusted.

Abstract: Preceding to the reading out of the recording information of the optical disk by the pick-up, the height of the foreign material existing at the light converging position on the information reading surface is detected by the detector, and when the height of the foreign material is higher than the floating height h of the SIL, the magnetic field is generated by applying the control current corresponding to the height of the foreign material to the coil as the magnetic field generator at the timing before the foreign material is moved to the information reading position of the pick-up by the rotation of the optical disk. Then, when the magnetic field is provided to the magnetic substance fixedly holding the SIL which is floating, the movement operation to separate the SIL to the higher position than the height of the foreign material from the information reading surface together with the magnetic substance, is conducted.

Abstract: There is provided an information recording apparatus having a vacuum system. The apparatus includes a vacuum chamber connected with a first evacuator device. An electronic beam producing device is partially enclosed in the vacuum chamber for emitting an electronic beam for recording information on a recording medium. A moving stage is provided in the vacuum chamber for linearly moving the recording medium in a vacuum atmosphere within the vacuum chamber. A spindle is disposed in the vacuum chamber for rotating the recording medium. The spindle is supported on an air bearing and is rotatably driven by a spindle motor. A magnetic fluid seal producing device is provided around the spindle close to the vacuum chamber side. A pressure differential chamber is provided around the spindle close to the air bearing side. The pressure differential chamber is connected with a second evacuator device.

Abstract: A polyurethane composition excellent in chlorine resistance containing 0.1 to 10% by weight, based on the polyurethane, of hydrotalcite which has water of crystallization and a C.sub.10 -C.sub.30 fatty acid adhered thereto, capable of being stably spun over a long period of time, and exhibiting neither discoloration in the step of tannin solution treatment nor swelling during chlorine immersion treatment.

Abstract: An information recording apparatus including a device for driving an optical-disk's master disk, an electron lens barrel for having an electron beam irradiate a recording surface of a disk, a translational device for producing, between the disk and the electron lens barrel, a relative movement in a direction parallel to the recording surface and a container for enclosing the elements of the apparatus adapted to support a vacuum atmosphere. The driving device includes a turn table 4, a spindle 14a for supporting the turn table, a motor 14 for driving the spindle, and a magnetic shield for preventing magnetic fields of the motor from leaking outward. The motor is enclosed in the shield to prevent its magnetic fields from affecting the electron beam, which makes it possible to record information with high accuracy. The use of the motor as a drive source realizes easier and more responsive control of the turn table than that in the prior art.