Sony Corporation

Yasuaki Maeda

Hideki Nagashima

Kazuhiko Fujiie

Ryo Ando

Kosuke Nakamura

Tadao Yoshida

Tetsu Watanabe

Yoshitaka Aoki

Takuya Kaeriyama

Hideo Obata

Naohiro Netsu

Tsutomu Harada

Hiroshi Mukawa

Hirotoshi Fujisawa

Yuji Arataki

Yoshimasa Utsumi

Masahiro Shigenobu

Masayuki Takezawa

Takashi Fujimoto

An optical recording medium is provided which has a substrate and a signal recording layer provided on the substrate and in which an information signal is recorded in the form of microscopic pits. A light beam is focused on the signal recording layer and some change of the light beam carried by a return light from the signal recording layer is detected to read the information signal recorded on the signal recording layer. The optical recording medium has a diameter of 65 mm or less and a thickness of 0.4 to 0.7 mm. An information signal recording area extends outwardly from a radial position of 12.5 mm or less from the center of the medium. The ratio in area between the information signal recording area and non-signal recording area is 3.4 or more. The storage capacity of this medium is 2 gigabytes or more. The optical recording medium has formed at the center thereof a center hole around which an annular table-abutment convexing to one side of the medium is formed. A magnetic-clamping hub is installed in the center hole and thus the medium is magnetically clamped to a rotation driving mechanism of an optical recording and/or reproducing apparatus. The compactness and high density of recording of the optical recording medium will contribute greatly to a further compact structure of a recording and/or reproducing apparatus in which the medium is to be used.

Optical recording medium and disc cartridge

The present invention relates to a skew control method and a skew control unit by which stable skew control can be performed with a simple configuration without the need for a dedicated skew sensor. Focus drive voltages Vand Vare measured at a plurality of points Pand Pset by moving an optical pick-upin the radial direction of an optical discin a state where a focus servo of the optical pick-upis ON, and skew angle control is performed so that Vand Vare equal to each other.

Skew control method and skew control unit

Read-only optical recording medium and disc cartridge

An optical recording medium is provided which has a substrate and a signal recording layer provided on the substrate and in which an information signal is recorded in the form of microscopic pits. A light beam is focused on the signal recording layer and some change of the light beam carried by a return light from the signal recording layer is detected to read the information signal recorded on the signal recording layer. The optical recording medium has a diameter of 65 mm or less and thickness of 0.4 to 0.7 mm. An information signal recording area extends outwardly from a radial position of 12.5 mm or less from the center of the medium. The ratio in area between the information signal recording area and non-signal recording area is 3.4 or more. The storage capacity of this medium is 2 gigabytes or more. The optical recording medium has formed at the center thereof a center hole around which an annular table-abutment convexing to one side of the medium is formed. A magnetic-clamping hub is installed in the center hole and thus the medium is magnetically clamped to a rotation driving mechanism of an optical recording and/or reproducing apparatus. The compactness and high density of recording of the optical recording medium will contribute greatly to a further compact structure of a recording and/or reproducing apparatus in which the medium is to be used.

Optical recording medium and disc cartridge having 2 GB capacity

A reproduction apparatus and method a recording apparatus and method by which two different kinds of data can be reproduced and recorded efficiently are disclosed. When main data are intermittently read in from a recording medium, periods within which reading in of the main data is not performed appear inevitably, and the periods are made use of to read in sub data from the recording medium, thereby allowing synchronized reproduction of the main data and the sub data which relate to the main data. On the other hand, when main data are intermittently written onto a recording medium, periods within which writing of the main data is not performed appear inevitably, and the periods are made use of to write sub data onto the recording medium, thereby allowing parallel recording of the main data and the sub data.

Recording/reproduction method and apparatus in which sub data is written/read in periods during which writing/reading of main data is not performed

In a memory control device for controlling the write-in/read-out operation for a memory of a recording/reproducing apparatus, a sector data storing area and an additive area are set in each sector-based data storing area in the memory. A prescribed data is stored in the additive area associated with the sector-based data stored in the sector data storing area. The access addresses for the additive area are generated on the basis of the sector count value when the sector data write-in or read-out is carried out in the memory. The access addresses are calculated by the memory control device.

Recording/reproducing device with memory controller which creates sector data storing area and additive data storing area

The invention provides a reproduction apparatus and method by which main data and sub data for modifying the main data can be reproduced in synchronism with each other readily by simple operation. Main data and sub data which are being reproduced in synchronism with the main data are searched in response to a searching operation of a user based on main data management information to be used for management of the main data or sub data management information to be used for management of the sub data to find out data to be reproduced in a unit of main data or sub data.

Apparatus and method for reproducing main data and sub data in synchronization

In a memory control device for controlling the write-in/read-out operation for a memory of a recording/reproducing apparatus, a sector data storing area and an additive area are set in each sector-based data storing area in the memory. A prescribed data is stored in the additive area associated with the sector-based data stored in the sector data storing areas. The access addresses for the additive area are generated on the basis of the sector count value when the sector data write-in or read-out is carried out in the memory. The access addresses are calculated by the memory control device.

Memory control and reproducing and/or recording apparatus for storage and access of memory location

A disc reproducing apparatus having a memory for temporary storage of data read from a disc. The memory is under the control of a memory controller which accesses data stored in the memory based on a generated address. The generated address is determined by a mode controller which can specify either the same address location, a previous location, or a later location depending upon the amount of data stored in the memory and errors which may occur in reading data from the disc.

Memory controller, reproducing apparatus mounting the same and method for controlling the same

A high speed dubbing is to be realized with two recording and/or reproducing units for compressed data. To this end, a magneto-optical disc,is read by an optical head,and compressed data produced via a decoder,are delivered to a memory,via a switch,. The data are then delivered to a magnetic head driving circuit,via an encoder,for direct writing on a magneto-optical disc,. In this manner, compressed data are directly dubbed without expansion to realize high speed dubbing.

Recording/reproducing apparatus for compressed data

There is provided a recording apparatus to perform the recording operation to a recording medium by receiving audio information as the main data and character information as subdata transmitted from a broadcasting station in view of extracting the partitioning code formed of the predetermined code included in the subdata, storing in memory an address recorded in a recording medium when the partitioning code is extracted, automatically performing the editing process based on the address stored in the memory when the audio information as the main data and character information as the subdata are recorded to the recording mediums and easily performing the searching operation during the reproducing operation.

Recording apparatus with a receiving function and recording apparatus

A high speed dubbing is to be realized with two recording and/or reproducing units for compressed data. To this end, a magneto-optical disc 32 is read by an optical head 33 and compressed data produced via a decoder 41 are delivered to a memory 14 via a switch 37. The data are then delivered to a magnetic head driving circuit 16 via an encoder 15 for direct writing on a magneto-optical disc 2. In this manner, compressed data are directly dubbed without expansion to realize high speed dubbing.

Recording and/or reproducing method and apparatus with dubbing mode

A memory controller is equipped with a memory data search circuit for carrying out an identifying operation of management information corresponding to a segment located in front of or behind a segment serving as a reference for an editing operation on a recording medium through search and comparison processing of managing information (U-TOC). The system controller does not receive search data and execute the data search but only sets the comparison standard and an initial value and outputs an execution control signal. The editing operation performed, reduces wasted space on a recording medium, such as a disc, and eliminates 'trash areas' which are not addressable in the U-TOC.

Growing community of inventors

Kanagawa, Japan

Yasuaki Maeda