Abstract: To provide a method for optimizing the optical output from an optical head when recording data onto an optical disk, each time a suspension of data recording onto the disk is determined, the optical head reads data recorded onto the disk before the suspension, and recording state of this data is judged. Based on the judged recording state, the optical output from the optical head to be emitted when resuming the data recording is controlled. A timing at which to suspend data recording can be desirably set, so that the recording state of the recorded data in the disk can be judged at desirable timing in data recording operation, so that the optical output from the optical head is controlled based on the judged recording state.

Abstract: Virtual recording cells are assumed within a groove on a recording layer of an optical recording medium. Recording marks with five or more different sizes are formed on each of the virtual recording cells by means of modulating the irradiation time of the laser beam in five levels or more in correspondence to the information to be recorded. The reflectance of the virtual recording cells modulates in many levels and the reflection level of the readout laser beam during regeneration is modulated in five levels or more.

Abstract: To implement light quantity monitoring with high frequency responsivity and correction of astigmatic differences of a semiconductor laser with a simple configuration with a fewer parts. Of the light beam output from a semiconductor laser light source 101, a peripheral beam component is entered by a light reflection element 107 into an anterior light monitoring photodetector 103 formed in the vicinity of a semiconductor laser light source 101. Furthermore, the surface of the reflection sphere of the light reflection element is formed anamorphic, and thus condensed to an appropriate size on the photodetector without being focused, providing high frequency responsivity. Furthermore, the light reflection element 107 is placed inclined at a predetermined angle so as to cancel out astigmatic difference of the optical semiconductor laser light source 101.

Abstract: A method and an apparatus are provided, which enable a user's standby time to be shortened or utilized effectively in the course of recording/reproduction of information with respect to an optical disk. Information recorded on a disk is reproduced preferentially, and after counting for a predetermined period of time, recording learning is conducted. Alternatively, management information is reproduced preferentially over recording learning, and recording learning is conducted while a user is confirming this information. Alternatively, the possibility of recording on a disk is identified, and reproduction preference or recording learning preference processing is conducted based the possibility. Alternatively, a rotation speed of a disk is controlled to be variable or constant, based on the possibility of recording.

Abstract: A device for recording and/or reproducing an optical record carrier (1), comprises an optical system for projecting a first, a second and a third optical beam at a first (11), a second (12) and a third spot (13) at the record carrier (1). The device further comprises detection elements primary position signals (D5, C, D1) which is indicative for an amount of radiation reflected by the record carrier at said thoses spots (11). The device further comprises signal processing means (34.1, . . . 34.4; 35.1, . . . 35.4) for generating a plurality of secondary position signals (S1, S2, S3, S4) in response to the primary position signals (D5, C, D1). A selection element (36) selects one of the position signals (S1, S2, D1, S3, S4) as an output signal (WRE) in response to a selection signal (SEL). The selection signal (SEL) is derived from the output signal (WRE) of the selection element (36).

Abstract: An optical disc apparatus for recording test data on a predetermined area of an optical disc under varied recording powers to determine an optimum recording power based on the quality of a signal obtained by reproducing the recorded test data. The test data is recorded under adverse recording conditions so as to evaluate the amount of change in quality of the reproduction signal. In order to create adverse recording conditions, the optical disc is tilted or the laser is defocused. A recording power for which the change in signal quality due to the deteriorated recording conditions is sufficiently small is determined as an optimum recording power capable of providing adequate recording margin.

Abstract: The present invention provides a recording medium having a plurality of charge accumulating regions each containing a first material capable of accumulating an electric charge and a photoconductive region containing a second material whose conductivity is increased by light absorption, a recording apparatus including such a recording medium, and a method recording information on such a recording medium. In the present invention, information is recorded on the recording medium by irradiating the photoconductive region with light and by injecting an electric charge into the charge accumulating region via that portion of the photoconductive region which is irradiated with light.

Abstract: A disk cartridge which allows for the user to know what contents are recorded in which disk cartridge without the need of reproducing the disk cartridge, a method of manufacturing the same and a recording/reproducing system using the same have been provided, in which the disk cartridge is accomplished by incorporating the optical disk in a case, a recording surface of the optical disk is comprised of an annular inner area, a clamping area, a transition area, an information recording area and a rim area, which are arranged from inside to outside in radial directions of the optical disk, and disk cartridge identification information is recorded in the transition area of the optical disk, and also the disk cartridge identification information recorded in the optical disk is provided discernibly from outside the case.

Abstract: In an optical disk apparatus, bit sequences of information regarding copyright are respectively scrambled using different binary sequences, thereby generating plural lines of signals. The plural lines of signals are further scrambled to generate a single line of drive signal, with which laser beam is modulated.

Abstract: A reproduction signal evaluation method of this invention includes the step of obtaining a reproduction signal from an information recording medium on which digital information is recorded with record marks having different sizes, the step of obtaining the amplitude of a first reproduction signal, of the signals contained in the reproduction signal, which reflects digital information recorded with a record mark having the maximum size, the step of obtaining the amplitude of a second reproduction signal, of the signals contained in the reproduction signal, which reflects digital information recorded with a record mark having the second smallest size, the step of obtaining an evaluation value from the ratio of the amplitudes of the first and second reproduction signals, and the step of evaluating a characteristic of the reproduction signal on the basis of the evaluation value.

Abstract: An optical information reproducing apparatus and a method of setting the quantity of light in an optical information reproducing apparatus that can be applied to an optical disk apparatus for accessing a phase-change-type optical disk for easily and reliably selecting conditions for driving a laser diode with a drive signal having a high-frequency signal superimposed thereon. The power of a laser beam is set such that the peak power of the laser beam except for a relaxation oscillation component does not exeed a power Pe required to erase data.

Abstract: An optical device and a recording medium are provided with a recording layer for recording information by radiation of light, and a mask layer which is formed closely to the recording layer, reduces its transmittance of light due to light or heat, and transmits light to the recording layer by using a near-field effect. An optical reproducing and recording method includes the steps of: emitting a laser beam onto the mask layer, generating a near field around an area of the mask layer that has transmittance being reduced by the laser beam, and reproducing or recording optical information in the recording layer by interaction between the near field and the recording layer. With this method, it is possible to provide the optical device, recording medium, and optical reproducing and recording method that can realize a high S/N ratio upon reproducing and recording and that can readily form a recording mark.

Abstract: Apparatus is disclosed for recovering both a data signal and a clock signal from an optical disk, in which nonconfocal detection is used to recover the data signal and confocal detection is used to recover the clock signal. The clock signal is recorded at a frequency slightly higher than the highest frequency components of the data signal, so the clock signal is not incorporated into the signal recovered by the nonconfocal data detector. The data and clock signals thereby can be recovered simultaneously from the optical disk, using just a single laser beam and objective lens.

Abstract: Provided is a medium for recording optical information and a method for recording optical information that allow recording sensitivity to be increased, and particularly a prescribed recording sensitivity to be maintained together with reflectivity and other playback characteristics during high-speed recording, by employing the temperature dependence of recording sensitivity of the light-absorbing layer instead of the light attenuation coefficient of the light-absorbing layer, and selecting a material which is prone to increased absorption of a laser beam at high temperatures during recording. A distinctive feature is that the absorbance or recording sensitivity of the dye material film used in the medium for recording optical information that has a writable structure is dependent on temperature. Specifically, it was found that the absorption spectrum of the dye material varies at high temperatures, and a relation A2/A1≧1.30 was established.