Abstract: A laser beam from a pickup is focused on an information recording medium, such as a DVD-R/RW, to record information. When the power of the laser beam is calibrated, the laser beam emitted from the pickup is received by a light receiving unit such as an FMD. The level of the received laser beam is detected, the power ratio of the laser beam is determined based on the result, and the power of the laser beam is calibrated so that the power ratio matches a predetermined reference power ratio. This method enables information to be recorded with optimum recording characteristic because the reference power ratio shows the power ratio for recording information at the optimum characteristics.

Abstract: Provided is an optical disk manufacturable by a conventional recording medium manufacturing method and that is capable of performing recording with an information recording apparatus used to perform recording on conventional recording mediums, and a data recording apparatus for recording contents data. An optical disk 100 has a structure in which a first substrate 110 and a second substrate 120 are bonded together. The first substrate is provided with a recording layer in which contents data is recorded, and the second substrate is provided with a visual information recording layer in which information enabling visual recognition of, for example, the contents of contents data or a title of the contents data is recorded as visual information.

Abstract: An information recording apparatus includes a pickup which irradiates a recording light to a disc on which prepits are formed and which outputs return light quantity data, a period determination circuit which determines a data obtaining period in which return light quantity is not affected by the prepit, a sample-hold circuit which obtains the return light quantity in the data obtaining period, and a microcomputer which controls a recording power based on the return light quantity data. The microcomputer obtains the return light quantity data in the data obtaining period in which the return light quantity is not affected by the prepit, and executes control including the recording power control based on the return light quantity data. As a sample-hold circuit detects a pit level and the like in a 9T to 11T period which is hardly affected by the LPP and controls the recording power based on the result, proper recording power control can be executed.

Abstract: A laser beam from a pickup is focused on an information recording medium, such as a DVD-R/RW, to record information. When the power of the laser beam is calibrated, the laser beam emitted from the pickup is received by a light receiving unit such as an FMD. The level of the received laser beam is detected, the power ratio of the laser beam is determined based on the result, and the power of the laser beam is calibrated so that the power ratio matches a predetermined reference power ratio. This method enables information to be recorded with optimum recording characteristic because the reference power ratio shows the power ratio for recording information at the optimum characteristics.

Abstract: A tilt correcting apparatus makes a tilt correction in an information recording apparatus or the like capable of recording record information onto an information recording medium, on an information recording surface of which a track having a wobble is formed, by emitting laser light thereonto. The tilt correcting apparatus is provided with: a correcting device for changing an irradiation angle of the laser light; a controlling device for controlling the correcting device such that the irradiation angle is set to be each of a plurality of predetermined angles before the record information is recorded; a wobble detecting device for detecting a wobble signal corresponding to the wobble from a photo-detection signal of light from the track caused by the laser light; and a tilt determining device for determining an amount of tilt of the information recording surface, on the basis of the detected wobble signal.

Abstract: An information recording apparatus includes a pickup which irradiates a recording light to a disc on which prepits are formed and which outputs return light quantity data, a period determination circuit which determines a data obtaining period in which return light quantity is not affected by the prepit, a sample-hold circuit which obtains the return light quantity in the data obtaining period, and a microcomputer which controls a recording power based on the return light quantity data. The microcomputer obtains the return light quantity data in the data obtaining period in which the return light quantity is not affected by the prepit, and executes control including the recording power control based on the return light quantity data. As a sample-hold circuit detects a pit level and the like in a 9T to 11T period which is hardly affected by the LPP and controls the recording power based on the result, proper recording power control can be executed.

Abstract: A pickup device has various controlled elements such as a light source and a sensor which need to be electrically controlled. The controlled elements are connected with an in-pickup control element via internal signal lines and are controlled by control signals supplied from the in-pickup control element. The in-pickup control element is connected with an external microcomputer via a connector and an external signal line and receives a control signal or the like from the microcomputer. With this structure, the controlled elements in the pickup device are basically controlled, not by the external microcomputer, but by the in-pickup control element. Therefore, the signal lines for supplying the control signals to the controlled elements can be short signal lines only in the pickup.

Abstract: In a pickup device used for a drive apparatus of an optical disc, a storage element is provided. The storage element stores individual characteristic information associated with the pickup device. For example, the storage element stores the individual characteristic information associated with the level of the recording light waveform which is output from the LD provided in the pickup device. In recording information, the microcomputer in the drive apparatus obtains the individual characteristic information from the storage element in the pickup device and executes information recording by using an optimum write strategy determined in consideration of the individual characteristic information. Accordingly, the difference in characteristics of pickup devices is removed, and improvement and stabilization of the recording characteristic can be realized.

Abstract: A spherical aberration correcting apparatus is incorporated in an information recording system and gives the system a function of correcting spherical aberration in a real-time and effective manner under a recording operation of pieces of information. The spherical aberration correcting apparatus comprises a recording unit, reflected-light level detecting unit, correction amount deciding unit, and spherical aberration correcting unit. The recording unit records a piece of information through radiation of an optical beam onto an optical disk. The detecting unit detects a level of light formed of the optical beam reflected from the optical disk under a recording operation for the information, while the deciding unit decides a correction amount for spherical aberration on the basis of the level of the reflected-light. The correcting unit corrects the spherical aberration by using the correction amount.

Abstract: In a spherical aberration correcting apparatus, a test recording unit is configured to perform a test recording on an optical disk. A characteristic obtaining unit is configured to obtain a characteristic corresponding to a parameter by the test recording. The parameter is correlated with a spherical aberration. A correction amount deciding unit is configured to decide an optimum correction amount of the spherical aberration so as to minimize the spherical aberration according to the characteristic of the parameter. A spherical aberration correcting unit is configured to correct the spherical aberration according to the optimum correction amount of the spherical aberration.

Abstract: The information recording and reproducing apparatus drives the light source based on the recording data to irradiate the laser pulses on the storage medium and forms the recording marks. The level of the laser pulse is varied between the write power level necessary to form the recording marks and the bias level during the mark periods. Since the bias level is set to be lower than the read power level necessary to reproduce recording marks, the quantity of the laser light irradiated onto the storage medium during the recording may be reduced, and the adverse effect due to the heat accumulation or the heat distribution can be diminished. As a result, the recording marks of appropriate shape can be formed on the storage medium, and the information recording accuracy can be improved.