Abstract: According to one embodiment, a method for information processing executed in an information processing apparatus processing recording data, including, dividing the recording data into a plurality of recording data blocks, recording management information on corresponding first management areas in n storage media, the n storage media comprising a first storage medium to an nth storage medium, wherein n comprises an integer equal to or larger than 2, and recording the recording data blocks on corresponding second management areas of the n storage media by a controller configured to control the information processing apparatus.

Abstract: According to one embodiment, a power supply apparatus includes a battery assembly, a fuse element, a switch unit, and a control unit. The fuse element is connected between the battery assembly and a load unit driven by being supplied with power from the battery assembly. The switch unit is connected in parallel to the load unit. The control unit causes, when an over voltage of at least one of the battery assembly and the load unit is detected, the switch unit to be in an ON state, provides an over current to flow from the battery assembly to the fuse element, and fusing the fuse element.

Abstract: According to one embodiment, a first encoder encodes main information, a second encoder encodes sub-information, a first modulator modulates a carrier based on an output of the first encoder, a duplicating module duplicates an output of the second encoder to generate encoded sub-information units, and a second modulator amplitude-modulates an output of the first modulator based on the encoded sub-information units. The second modulator amplitude-modulates with ?/(?×(2N)1/2) being 0.4 or less, wherein a noise power of a transmission path or a storage medium is ?2, a number of the encoded sub-information units is N, signal levels after amplitude modulation, which correspond to bit 1 and bit 0 of the encoded sub-information units, are A and B, and a level difference A?B is ?.

Abstract: The length of a format modulation area in an address segment is limited to be 25% of the address-segment length or less, and the position of the format modulation area is selectable two possible positions. Subsequently, where a CLV optical-disk medium is used, wobble modulation areas in adjacent recording tracks do not overlap each other in the radius direction.

Abstract: According to one embodiment, a first encoder encodes main information, a second encoder encodes sub-information, a first modulator modulates a carrier based on an output of the first encoder, a duplicating module duplicates an output of the second encoder to generate encoded sub-information units, and a second modulator amplitude-modulates an output of the first modulator based on the encoded sub-information units. The second modulator amplitude-modulates with ?/(?×(2N)1/2) being 0.4 or less, wherein a noise power of a transmission path or a storage medium is ?2, a number of the encoded sub-information units is N, signal levels after amplitude modulation, which correspond to bit 1 and bit 0 of the encoded sub-information units, are A and B, and a level difference A?B is ?.

Abstract: The length of a format modulation area in an address segment is limited to be 25% of the address-segment length or less, and the position of the format modulation area is selectable two possible positions. Subsequently, where a CLV optical-disk medium is used, wobble modulation areas in adjacent recording tracks do not overlap each other in the radius direction.

Abstract: According to one embodiment, an optical head device provides a signal processing circuit which sets a control amount to move an objective lens so that a distance between the objective lens and a given recording layer of the an optical disc coincides with a focal position, an optical path length correction mechanism which corrects an influence of an aberration component producing an error in the focal distance, a thickness difference detection circuit which finds an amount of correction to be made by the optical path length, and an aberration correction circuit which generates a correction signal to correct the influence of the aberration component producing the error in the focal distance detected by the thickness difference detection circuit, and supplies the correction signal to the optical path length correction mechanism.

Abstract: According to one embodiment, an apparatus which records a signal in a recording medium in which information is written by using a first laser having a first wavelength and from which information is read by using a second laser having a second wavelength longer than that of the first laser, a signal is recorded in the recording medium by using the first laser, and a control section reproduces the signal recorded with the first laser and measures a first amount that is used to calculate a target value for optimization of recording conditions, reproduces a signal recorded with the second laser and measures a second amount for optimization of a reproduction signal, compares the first amount with the second amount, and determines the first amount under the recording conditions where the second amount becomes optimum as a target value for optimization of the recording conditions.

Abstract: In an optical disk medium, land recording tracks (1) are coupled by first and second coupling portions (3 and 4) at a particular radial position to form a tilt detecting mark SM.

Abstract: The length of a format modulation area in an address segment is limited to be 25% of the address-segment length or less, and the position of the format modulation area is selectable two possible positions. Subsequently, where a CLV optical-disk medium is used, wobble modulation areas in adjacent recording tracks do not overlap each other in the radius direction.

Abstract: This invention relates to a focus control apparatus having a controller which generates a control signal and performs focus operation when the peak timing of a focus sum signal based on reflected light and the zero-crossing timing of a focus error signal are detected to substantially coincide with each other in supplying a control signal to a lens actuator driver for supplying a driving signal to a lens actuator for driving a lens. The invention also relates to an optical disk apparatus using the focus control apparatus. By detecting coincidence of the two timings, two reflected waves are discriminated, and stable focus operation is achieved.

Abstract: A recording data string is composed of a plurality of synchronous frames each of which has synchronous data and coding data. Data items in the coding data contributed to creation of the same column of the error correction code are arranged at regular intervals of E in the recording data string. A data segment length L is obtained by adding an additional synchronous frame to the recording data string. Wherein, a physical segment length A satisfies the equation L=mA, m is a natural number. And A is set indivisible by E.

Abstract: An optical disk apparatus has a first optical system having an objective lens with a first NA, a second optical system having an objective lens with a second NA lower than the first NA, an addition mechanism for adding focus error signals detected by the first and second optical systems, and an alignment mechanism for aligning the objective lens in accordance with the addition result of the addition mechanism.

Abstract: An information recording medium according to an embodiment of this invention has a plurality of disk-like information recording layers, which are adhered to each other within an allowable decentering error range, and an embossed lead-in area assured on each information recording layer has first guard tracks which are formed within the range of the first radial distance from the radial position of the innermost periphery of the embossed lead-in area toward the outer periphery side, and second guard tracks which are formed within the range of the second radial distance from the radial position of the outermost periphery of the embossed lead-in area toward the inner periphery side.

Abstract: An information recording medium according to an embodiment of this invention has a plurality of disk-like information recording layers, which are adhered to each other within an allowable decentering error range, and a data area assured on each information recording layer, and has guard tracks within the range of a predetermined radial distance from the radial position of the innermost periphery of the data area toward the outer periphery.

Abstract: In an optical disk medium, land recording tracks (1) are coupled by first and second coupling portions (3 and 4) at a particular radial position to form a tilt detecting mark SM.

Abstract: An optical disk according to the invention has a lead-in area in which information concerning characteristics of an optical head for use in recording or reproducing the information and an optimum condition of a light beam for recording the information on the optical disk or reproducing the information from the optical disk are recorded.

Abstract: An optical disk apparatus has a first optical system having an objective lens with a first NA, a second optical system having an objective lens with a second NA lower than the first NA, addition means for adding focus error signals detected by the first and second optical systems, and alignment means for aligning the objective lens in accordance with the addition result of the addition means.

Abstract: An optical disk apparatus has a first optical system having an objective lens with a first NA, a second optical system having an objective lens with a second NA lower than the first NA. The optical disk apparatus at the time of processing the optical disk, when the optical system suitable recording/reproduction process of the optical disk is the second optical system, via the first optical system detecting a surface run-out of the optical disk and execute the focus lead-in process of the second optical system on the basis of a surface run-out detected; and when at the time of processing the optical disk, when the optical system suitable recording/reproduction process of the optical disk is the first optical system, processing the optical disk with the first optical system without detecting the surface run-out of the optical disk.

Abstract: The length of a format modulation area in an address segment is limited to be 25% of the address-segment length or less, and the position of the format modulation area is selectable two possible positions. Subsequently, where a CLV optical-disk medium is used, wobble modulation areas in adjacent recording tracks do not overlap each other in the radius direction.