Pioneer Corporation

Memory-tech Holdings Inc.

Pioneer Digital Design and Manufacturing Corporation

Takao Tagiri

Seiro Oshima

Masahiro Kato

Eiji Muramatsu

Atsushi Yamaguchi

Masayoshi Yoshida

Hideki Kobayashi

Shoji Taniguchi

Makoto Suzuki

Masakazu Ogasawara

Yoshio Sasaki

Tatsuhiro Yone

Toshihiko Takishita

Toshihiko Maruyama

Takuya Shiroto

Yasuo Hosoda

Tomoyuki Miyamoto

Masataka Yamaguchi

Takahiro Togashi

Makoto Matsukawa

Katsunori Obata

Kazuhiro Yamato

An electromagnetic wave transmission cable for transmitting an electromagnetic wave comprises a hollow waveguide tube and a foamed resin member. The hollowing waveguide tube includes a hollow dielectric layer formed in a tubular shape. The foamed resin member is provided over a predetermined length in a longitudinal direction of the hollow waveguide tube and covers a surface of the dielectric layer to surround an outer periphery of the hollow waveguide tube.

Electromagnetic wave transmission cable including a hollow dielectric tube surrounded by a foamed resin member having different expansion ratios at different regions therein

A recording medium is provided with: a guide layer on which a guide track or tracks are formed; and a plurality of recording layers, wherein a same mark group is formed in a same rotational phase position of each of a plurality of guide tracks which are included in a beam spot of guide laser light, the mark group including a pair of record marks which are shifted by a predetermined distance toward a right side and a left side, respectively, from a track center.

Recording medium

A recording medium is provided with: a guide layer on which a guide track or guide tracks are formed; and recording layers, wherein (i) an information mark group and (ii) a distinctive mark group are formed in the guide layer, the information mark group being formed on each of a plurality of guide tracks, the distinctive mark group distinguishing a center track out of the plurality of guide tracks on each of which the information mark group is formed, the distinctive mark group including a pair of distinctive record marks which are shifted toward a right side and a left side, respectively, from a track center of the center track, a width of each distinctive record mark is twice or more a width of the guide track.

An optical-recording medium is provided with at least a first recording layer for recording information optically; and a second recording layer for recording information optically by a light beam that passes through said first recording layer; wherein the track pitch of a recording track that is formed on said second recording layer is narrower than the track pitch of a recording track that is formed on said first recording layer.

Optical recording medium, information recording apparatus and information reproduction apparatus

An offset amount measuring method is provided with: a recording process for measurement (i) of recording information for measurement, into a recording track in the Llayer, by a predetermined section, from a measurement reference position, and of (ii) recording the information for measurement, into a recording track in the Llayer, by the predetermined section, from or toward a measurement correspondence position, which is associated with the measurement reference position by the pre-format address; a first detecting process of detecting a border of a first recorded area in which the information for measurement is recorded and a first unrecorded area in the first recording track, on the basis of a difference in reflectance between the first recorded area and the first unrecorded area; a second detecting process of detecting a second border position in the recording track in the Llayer, on the basis of a difference in reflectance; and a determining process of determining the offset amount, on the basis of the detected first and second border positions. Moreover, it is also provided with a judging process of judging whether or not the determined offset amount is within tolerance with respect to the first offset amount set in advance for offset countermeasures.

Offset amount measuring method and apparatus

A groove track and a land track are alternately and spirally formed on an information recording medium. On the land track neighboring the groove track, pre-information indicating position information of a track on a disc is formed as a prepit. On the information recording medium, an embossed area is formed so that information about a copyright and for preventing an illegal copy cannot be rewritten. In the embossed area, an embossed configuration including a pit and a space of predetermined depths is formed. The prepit in the embossed area is formed so that the prepit has an optimized configuration according to a pit length and a space length in the embossed area which the prepit neighbors. Consequently, interference between the embossed configuration and the prepit can be prevented even in a case that the prepit is formed in addition to the embossed configuration in the embossed area.

Information recording medium

The present invention provides an optical recording medium, in which levels of wobble signals extracted from a recording area formed snakily, a reproduction exclusive area and an impossible area are maintained constant. On DVD-RW, groove tracks are snakily formed on a groove section on which recording information is recorded, and pit strings where a plurality of phase pits wave are arranged on the impossible area and the reproduction exclusive area which prevent illegal copying. On the respective areas, pit depths (groove depths), duty of the pit strings and wobbling amplitudes are set according to predetermined conditions so that the output levels of the wobble signals extracted based on the wobbling amplitudes can be maintained constant on the respective areas. As a result, synchronous control can be made accurately at the time of recording and reproduction on/from the DVD-RW.

Optical recording medium, optical recording medium producing apparatus and optical recording medium producing method

A rewritable optical recording medium includes a segmented groove area in which the groove track is segmented along a rotating direction of the recording medium by groove non-forming portions to form a plurality of groove portions; and a continuous groove area in which a continuous groove is formed, the continuous groove having a groove width smaller than a groove width in the segmented groove area.

Rewritable optical recording medium and manufacturing method and apparatus therefor

Optical recording medium having a plurality of meandering groove tracks, optical recording medium producing apparatus and optical recording medium producing method

A recording medium includes pairs of groove tracks and land tracks having periodically formed bent portion provided side by side on a substrate, a plurality of land prepits previously formed on the land tracks and carrying information about the groove tracks, and a recording layer formed on at least the groove tracks and the land tracks. The land prepits have a radius of mean curvature smaller than a radius of mean curvature of sides of the groove tracks in land-prepit absent regions of the land prepits and are defined by curved surfaces continuously extending from the sides of the groove tracks. Those sides of the groove tracks which face the continuous curved surfaces of the land prepits are curved surfaces that stricture the groove tracks. The depth of the land prepit is larger than that of the groove track.

Growing community of inventors

Koufu, Japan

Takao Tagiri