Abstract: The magnetic recording and reproducing apparatus reads a transfer clock synchronized with servo information and records a write-once clock pattern in a state where 0 is set as a delay time of the delay device 13 and 1 is set as the dividing ratio of the frequency divider 17. The apparatus corrects the delay time according to the output of the phase comparator 14 which changes on the basis of the phase difference and rewrites a write-once clock pattern. Rotation of the magnetic disk, detection of the phase difference and correction of the delay time are repeatedly preformed until no change occurs in the output of the phase comparator 14. After the output stops changing, preformat information patterns excluding the servo information pattern are recorded as fine patterns by changing the dividing ratio of the frequency divider 17 to multiply the frequency.

Abstract: A thermally assisted magnetic recording method is implemented for a storage disk with a magnetic recording layer which includes recording areas and non-recording areas. In this method, a heating laser is moved relative to the disk in facing relation to the magnetic recording layer for locally heating the recording areas. As the laser spot transitions from a recording area to the subsequent non-recording area, the heating is stopped. In cooperation with the heating laser, a magnetic field applier locally magnetizes the recording areas of the magnetic recording layer for recording signals. As the magnetic field applier transitions from a recording area to the subsequent non-recording area, the application of the magnetic field is stopped after the heating by the heating laser is stopped.

Abstract: A thermally assisted magnetic recording method is implemented for a storage disk with a magnetic recording layer which includes recording areas and non-recording areas. In this method, a heating laser is moved relative to the disk in facing relation to the magnetic recording layer for locally heating the recording areas. As the laser spot transitions from a recording area to the subsequent non-recording area, the heating is stopped. In cooperation with the heating laser, a magnetic field applier locally magnetizes the recording areas of the magnetic recording layer for recording signals. As the magnetic field applier transitions from a recording area to the subsequent non-recording area, the application of the magnetic field is stopped after the heating by the heating laser is stopped.

Abstract: A master is used for writing information to a magnetic recording disk by a magnetic transfer method. The recording disk includes a magnetic recording layer possessing vertical magnetic anisotropy. The master includes a servo zone corresponding part formed with a magnetic material pattern for recording servo information to the recording layer of the recording disk. The master also includes a user data zone corresponding part formed with a second magnetic material pattern for providing the recording layer of the recording disk with a dummy signal.

Abstract: An information recording medium characterized by comprising a plurality of kinds or a plurality of sets of servo information recorded as magnetic information and used for detecting a position of the information recording medium relative to a magnetic head. Even if some sets of servo information become defective, the information recording medium is not determined as a defective, and user data can be recorded and reproduced on the information recording medium by utilizing servo information of another set which is determined to be normal.

Abstract: A master medium for magnetic transfer includes a substrate having a concave portion formed in its surface corresponding to a pattern of recorded information to be transferred; a first perpendicular ferromagnetic layer deposited in the concave portion; and a second perpendicular ferromagnetic layer layered on the substrate surface and the first perpendicular ferromagnetic layer surface. The substrate surface and the first perpendicular ferromagnetic layer surface are flattened to form a single flat surface. In the master medium for magnetic transfer, a magnetic field change in a direction parallel to the substrate surface at a magnetization boundary of the first perpendicular ferromagnetic layer is steep. Since the influence of the change of an external magnetic field is reduced, it is possible to perform accurate transfer from the master medium for magnetic transfer to a slave medium for magnetic recording.

Abstract: The magnetic recording and reproducing apparatus reads a transfer clock synchronized with servo information and records a write-once clock pattern in a state where 0 is set as a delay time of the delay device 13 and 1 is set as the dividing ratio of the frequency divider 17. The apparatus corrects the delay time according to the output of the phase comparator 14 which changes on the basis of the phase difference and rewrites a write-once clock pattern. Rotation of the magnetic disk, detection of the phase difference and correction of the delay time are repeatedly preformed until no change occurs in the output of the phase comparator 14. After the output stops changing, preformat information patterns excluding the servo information pattern are recorded as fine patterns by changing the dividing ratio of the frequency divider 17 to multiply the frequency.

Abstract: An initialization magnetic field Hi as an external magnetic field is applied in a direction crossing (perpendicularly) the surface of the substrate 10 to initialize the medium 1, so that the first magnetic film 11 and the second magnetic film 12 can be initialized simultaneously. In this method for initializing a medium, the magnetization direction of the initialization magnetization H1i at the first magnetic film 11 and the magnetization direction of the initialization magnetization H2i at the second magnetic film 12 accord with each other with regard to a direction crossing the substrate 10.

Abstract: The present invention provides a magnetic recording unit, including: a magnetic head; a magnetic recording medium having a servo pattern for adjusting a position of the magnetic head; a frequency detecting element for detecting a frequency in the servo pattern on a track corresponding to the position in a radial direction of the magnetic recording medium, on the basis of a reproduction signal obtained by reading the servo pattern with the magnetic head; a storage element for storing in advance information on predetermined frequencies corresponding to the positions of tracks of the magnetic recording medium; a tracking element for comparing the frequency detected on the track by the frequency detection element and the information on the frequency corresponding to the same track, the information being stored in the storage element, and for generating a signal for adjusting the position of the magnetic head, the signal being generated on the basis of a difference between the frequencies.

Abstract: A master medium for magnetic transfer includes a substrate having a concave portion formed in its surface corresponding to a pattern of recorded information to be transferred; a first perpendicular ferromagnetic layer deposited in the concave portion; and a second perpendicular ferromagnetic layer layered on the substrate surface and the first perpendicular ferromagnetic layer surface. The substrate surface and the first perpendicular ferromagnetic layer surface are flattened to form a single flat surface. In the master medium for magnetic transfer, a magnetic field change in a direction parallel to the substrate surface at a magnetization boundary of the first perpendicular ferromagnetic layer is steep. Since the influence of the change of an external magnetic field is reduced, it is possible to perform accurate transfer from the master medium for magnetic transfer to a slave medium for magnetic recording.

Abstract: The present invention is a system capable of protecting copyright and personal information appropriately and allowing users to readily obtain desired contents in a short time at low prices. A recording device stores contents in advance. The recording device encrypts the contents, based on an identifier given uniquely to a medium. The recording device records the encrypted contents on the medium. Moreover, the recording device records limiting conditions for reproducing, displaying or executing the contents on the medium. An execution device decrypts the contents recorded on the medium, based on the identifier. The execution device reproduces, displays or executes the contents under the limiting conditions recorded on the medium.

Abstract: An apparatus for testing a circuit board has a holder for holding the circuit board, a detector for detecting the electrical characteristics of the circuit board, and a controller for controlling laser plasma switches. The detector has a path forming unit positioned away from the circuit board by a predetermined gap. The path forming unit forms a first conductive path between a position corresponding to a first test pad on a trace of the circuit board and a first power source, as well as a second conductive path between a position corresponding to a second test pad on another trace of the circuit board and a second power source. The controller emits a laser beam to a first space between the first test pad and the first conductive path and another laser beam toward a second space between the second test pad and the second conductive path, to make the first and second spaces conductive.

Abstract: An electrooptic voltage waveform measuring apparatus, which includes an electrooptic element having an electrooptic effect; a first electrode mounted on the electrooptic element and electrically coupled to an object to be measured; and a first light source irradiating a light on the electrooptic element. The electrooptic voltage waveform measuring apparatus further includes a polarization analyzer for analyzing a polarization state of the light passed through the electrooptic element and detecting a voltage waveform of the object; a second electrode mounted on the electrooptic element and separated from the first electrode; and an amplifier having an input terminal coupled to the second electrode and outputting a low-frequency component of the voltage waveform of the object.

Abstract: An apparatus for testing a circuit board has a holder for holding the circuit board, a detector for detecting the electrical characteristics of the circuit board, and a controller for controlling laser plasma switches. The detector has a path forming unit positioned away from the circuit board by a predetermined gap. The path forming unit forms a first conductive path between a position corresponding to a first test pad on a trace of the circuit board and a first power source, as well as a second conductive path between a position corresponding to a second test pad on another trace of the circuit board and a second power source. The controller emits a laser beam to a first space between the first test pad and the first conductive path and another laser beam toward a second space between the second test pad and the second conductive path, to make the first and second spaces conductive.

Abstract: An electrooptic voltage waveform measuring apparatus, which includes an electrooptic element having an electrooptic effect; a first electrode mounted on the electrooptic element and electrically coupled to an object to be measured; and a first light source irradiating a light on the electrooptic element. The electrooptic voltage waveform measuring apparatus further includes a polarization analyzer for analyzing a polarization state of the light passed through the electrooptic element and detecting a voltage waveform of the object; a second electrode mounted on the electrooptic element and separated from the first electrode; and an amplifier having an input terminal coupled to the second electrode and outputting a low-frequency component of the voltage waveform of the object.

Abstract: A voltage and displacement sensitive probe with an electro-optic crystal, electrically conductive transparent films and adhered to a pair of parallel surfaces on the electro-optic crystal, a transparent elastic film which circumferential portion is bonded to the frame and which is symmetric with respect to any plane through the axis thereof, a probing needle bonded at its reflective bottom surface to the central portion on the film, a holder for holding the electro-optic crystal and the transparent elastic film via frame concentrically, a lead for grounding, and electrically conductive films for connecting between the films. Displacement detection of the probing needle is based upon the change in the length of the path of the light travelling through the electro-optic crystal being reflected by the surface and travelling in reverse direction. Voltage detection of the probing needle is based upon the phase difference between the two linearly-polarized light components.

Abstract: An apparatus for testing a circuit board has a holder for holding the circuit board, a detector for detecting the electrical characteristics of the circuit board, and a controller for controlling laser plasma switches. The detector has a path forming unit positioned away from the circuit board by a predetermined gap. The path forming unit forms a first conductive path between a position corresponding to a first test pad on a trace of the circuit board and a first power source, as well as a second conductive path between a position corresponding to a second test pad on another trace of the circuit board and a second power source. The controller emits a laser beam to a first space between the first test pad and the first conductive path and another laser beam toward a second space between the second test pad and the second conductive path, to make the first and second spaces conductive.

Abstract: A voltage and displacement sensitive probe with an electro-optic crystal, electrically conductive transparent films and adhered to a pair of parallel surfaces on the electro-optic crystal, a transparent elastic film which circumferential portion is bonded to the frame and which is symmetric with respect to any plane through the axis thereof, a probing needle bonded at its reflective bottom surface to the central portion on the film, a holder for holding the electro-optic crystal and the transparent elastic film via frame concentrically, a lead for grounding, and electrically conductive films for connecting between the films. Displacement detection of the probing needle is based upon the change in the length of the path of the light travelling through the electro-optic crystal being reflected by the surface and travelling in reverse direction. Voltage detection of the probing needle is based upon the phase difference between the two linearly-polarized light components.

Abstract: In a signal measuring apparatus a distance between a sample and a probe is adjusted, a voltage is applied through the sample and the probe and a signal is measured using a current flowing through the sample and the probe. That is, a current flowing through the sample and the probe is chopped by a laser beam at a prescribed frequency and is fetched into a sampling apparatus to generate a sample value of the current. The sample value is compared with a current setting value arbitrarily set in a comparator, and a reference voltage is generated according to a compared result in a control logic circuit and a D/A converter. The reference voltage is fed back to the sampling apparatus to converge the current flowing through the sample and the probe at the current setting value. Therefore, a signal of the sample is measured according to the reference voltage on condition that the current is converged at the current setting value.

Abstract: A probing device includes a minute probe in which at least an end portion is formed by conductive material, a cantilever having one end to which the probe is attached, and another end fixed to a moving member movable relatively to a sample in each direction of X, Y and Z, a unit for moving the moving member relatively to the sample, a transducing unit for generating information of voltage or current by means of light, a connecting unit having a low electric resistance, for connecting the transducing unit and the end portion of the probe, a detecting unit for detecting a change in a physical amount occurring in the cantilever by a force caused between the probe and the sample by a relative proximity of the moving member to the sample, and a voltage measuring unit for measuring a voltage at a measurement point on the sample, which is determined based on an output of the detecting unit, by way of the transducing unit when the probe is contacted with the measurement point.