摘要:
A record carrier for recording, reproducing and erasing information. A circular disc-like substrate has a recording layer thereon such that information is written onto the recording layer by changing the direction of magnetization. A guide groove of a plurality of tracks is formed in advance and extends in the radial direction with flat portions therebetween. Each flat portion between the tracks of the guide groove is divided into a plurality of sectors, each of which includes a header portion in which a header signal containing an address for distinguishing at least a respective sector is formed in advance with pits of a phase structure and a data portion adjacent to the header portion. The guide groove serves as an optical guide for a light beam which records, reproduces and erases information onto the data portion.
摘要:
A record carrier for recording, reproducing and erasing information. A circular disc-like substrate has a recording layer thereon such that information is written onto the recording layer by changing the direction of magnetization. A guide groove of a plurality of tracks is formed in advance and extends in the radial direction with intervals therebetween. Each track of the guide groove is divided into a plurality of sectors, each of which includes a header portion in which a header signal containing an address for distinguishing at least said sector is formed in advance with pits of a phase structure and a data portion adjacent to said header portion. The guide groove serves as an optical guide for a light beam which records, reproduces and erases information onto the data portion. A first detection system for detecting the light intensity of the reflected light from the record carrier and a second detection system for detecting the direction of polarization of the reflected light from the record carrier, and a level adjustment circuit for adjusting the levels of the header signal detected by the first detection system and the data signal detected by the second detection system are incorporated in this apparatus, whereby recording, reproducing and erasing information of any number of sectors are enabled.
摘要:
According to this invention, since the range of power necessary for erasing an overwritable magneto-optical recording medium is set to 2.5 mW or above, overwriting is possible without erase residue due to mark (magnetic domain) diameter difference, tracking offset, ambient temperature variation and characteristic dispersion between magneto-optical recording media and thus the magneto-optical recording medium has high reliability. Moreover, the rate of change, K of the switching field of the memory layer relative to temperature at around an erase start temperature can be controlled to be a constant value so that an erase power margin can be increased and that the tolerance to the reading light when the ambient temperature rises can be improved.
摘要:
Method and apparatus for processing information on a recording member having a recording film capable of recording and erasing information in accordance with the change of a magnetizing direction, by utilizing a light induced thermo-magnetic effect, in which before the intensity of the laser light is switched at the high level eliminating the magnetization of the recording film in order to effect the recording and erasing operations by focusing the laser light on the recording film as a light spot, a magnetic field with the predetermined direction according to the recording and erasing operations is previously applied on the recording film, whereby the recording and erasing operations of the magnetized information can be effected with high speed and stably by applying the normal magnetic field in the direction according to the recording and erasing operations respectively.
摘要:
An optical information recording apparatus, in which marks having a desired shape are recorded at desired positions, independently of the patterns of recording pulses, while canceling influences of the heat conduction from the mark, which has been directly previously recorded, by controlling the energy at the front end portion of laser light pulses, depending on the interval from the directly preceding pulse, when recording medium is irradiated with the laser light pulses corresponding to recording pulses so as to record information.
摘要:
An optical head for a magneto-optical memory in which the major axis (the phase advance axis or phase lag axis) of optical anisotropy of a lens focusing a linearly polarized laser beam onto a magneto-optical recording medium is arranged to coincide with the direction of linear polarization of the laser beam incident upon the lens, thereby improving the extinction ratio.
摘要:
A data recording/reproduction method and apparatus uses an optical disk equipped with wobbling track guide grooves disposed in a track scanning direction and minutely wobbled. The apparatus uses a circuit for detecting and correcting displacement of an optical spot position from the wobbling track, and a system for allowing data to correspond to front and rear edges of recording pits as a recording system, and includes a circuit for independently handling reproduction pulses obtained from reproduction signals of the recording pits on the front and rear edge sides and for generating reproduction clocks. A circuit resynthesizes the two series of reproduction pulse trains by a specific pattern portion in the data. Another optical disk apparatus divides each track into zones, and switches a rate of revolution each zone to attain a substantially equal linear velocity. A servo signal reproduction clock generation circuit and a data signal recording/reproduction clock generation circuit are disposed separately. The latter changes a frequency division ratio in accordance with the zones so that a clock having a predetermined frequency can be generated even when the rate of revolution changes.
摘要:
The present invention provides a non-aqueous electrode secondary battery supplied with a non-aqueous electrolyte comprising an overcharge additive. The positive electrode material layer constituting the positive electrode in the non-aqueous electrolyte secondary battery is characterized by having a differential pore volume peak A as well as a peak B located on the smaller pore diameter side than the peak A in a pore diameter range of 0.05 μm to 2 μm in a pore size distribution curve measured by a mercury porosimeter, wherein the pore size distribution curve has a minimum C corresponding to a minimum differential pore volume between the peak A and the peak B, such that a ratio (XC/XL) of the minimum C's differential pore volume XC to a differential pore volume XL, which is the larger between the peak A's differential pore volume XA and the peak B's differential pore volume XB is 0.6 or larger.
摘要:
A grinding abnormality monitoring method and device for grinding a plurality of works of the same type are proposed which can improve the accuracy of judgment whether an abnormality is generated or not by properly setting a threshold value. According to the method or the device, by setting at least one of upper and lower limit values of a trial grinding load detected at the trial grinding of at least one of the works, an occurrence of grinding abnormality is judged when an actual grinding load detected at the actual grinding of work exceeds at least one of the upper and lower limit values thereof which varies depending on the time elapsed from the start of the actual grinding or a position of work relative to a grinding wheel.
摘要:
Provided is an electric compressor whose manufacturing cost is reduced and in which a motor driving circuit can be positively protected. A temperature sensor is provided in the vicinity of a power semiconductor element whose temperature becomes highest among a plurality of power semiconductor elements and control of the number of revolutions of a motor is performed on the basis of temperatures detected by the temperature sensor, whereby it is possible to change the number of revolutions of the motor by using a temperature in the vicinity of a power semiconductor element in a position under the worst temperature conditions as a reference, and it becomes possible to positively protect an inverter circuit without the need for a plurality of temperature sensors.