Kabushiki Kaisha Toshiba

Matsushita Electric Industrial Co., Ltd.

Tokyo Shibaura Denki Kabushiki Kaisha

Kasai Kogyo Co., Ltd.

Pioneer Electronic Corporation

Memory-tech Corporation

Hitachi, Ltd.

Nippon Hoso' Kyokai

Panasonic Corporation

Hisashi Yamada

Tadashi Kobayashi

Taku Kato

Hideo Ando

Tadashi Kojima

Tomoo Yamakage

Tooru Kamibayashi

Hideki Mimura

Shinichiro Koto

Makoto Tatebayashi

Shunji Harada

Koichi Hirayama

Hirofumi Muratani

Toshihiro Sugaya

Naoki Endoh

Toru Kambayashi

Yasuhiro Ishibashi

Toshiyuki Shimada

Kenjiro Endoh

Takehisa Kato

Masafumi Tamura

Isao Hoshino

Hiroharu Satoh

Hideyuki Toma

Kouya Tochikubo

Toru Kamibayashi

Akio Tanaka

Kazuhiko Taira

Hiroaki Unno

Shinichi Tanaka

Takao Arai

Toshifumi Takeuchi

Yoshiaki Moriyama

Hiroshi Iwasaki

Akihiro Kasahara

Naomasa Nakamura

Atsushi Ishihara

Fumihiko Yokogawa

Seigo Ito

Toyoki Taguchi

Hiromichi Kobori

Masato Otsuka

Nobuhisa Yoshida

Akira Kurahashi

Tsutomu Sugawara

Kentaro Torii

Kei Shimura

Katsumi Narimatsu

Taku Katoh

Yasuyoshi Nishikawa

Shoichi Itoh

Katsumi Fukuchi

Kazuhiro Tokunaga

Takashi Tsubosaki

Masao Doumae

Fumihiko Saito

Hiroshi Kobayashi

Kazuo Watabe

Yuji Nagai

Akihito Ogawa

Chosaku Noda

Yasufumi Tsumagari

Naoki Morishita

Hideyuki Nishizawa

Minoru Tanaka

Katsutaro Ichihara

Akiko Hirao

Shin-ichi Tanaka

Kazuto Kuroda

Hiroshi Tanimoto

Tomoya Kodama

Kazuki Matsumoto

Koji Maruyama

Yukimasa Uchida

Takeshi Horiuchi

Toshihiko Kaneshige

Teruo Murakami

Yasuji Sato

Masayuki Tsurusaki

Takeshi Saito

Masahiko Tanaka

Shoichi Shimizu

Hideaki Ohsawa

Naobumi Seo

Akira Maekawa

Hiroharu Sato

Sadanari Fujimoto

Junichi Uota

Masaru Sakurai

Masaharu Obara

Kouichi Hirayama

Nobumasa Naito

Shunichi Ohnishi

Seiichi Ohgoshi

Noboru Katsuta

Tooru Kambayashi

Fumihiko Pioneer Electronic Corp Yokogawa

Yoshiaki Pioneer Electronic Corp Moriyama

An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam. The distance between the recording surface of the substrate and the light incident surface is smaller than a thickness of the substrate, and a surface roughness 'R' of the light incident surface meets a relationship represented by the following formula (1):R&#x2266;&#x3bb;/(8n) &#x2003;&#x2003;(1)

Information recording medium and method of manufacturing resinous substrate for use in the recording medium

An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam. The distance between the recording surface of the substrate and the light incident surface is smaller than a thickness of the substrate, and a surface roughness 'R' of the light incident surface meets a relationship represented by the following formula (1):R&#x2266;&#x3bb;/(8n)&#x2003;&#x2003;(1)

An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam. The distance between the recording surface of the substrate and the light incident surface is smaller than a thickness of the substrate, and a surface roughness 'R' of the light incident surface meets a relationship represented by the following formula (1):R&#x2266;&#x3bb;/(8n)&#x2003;&#x2003;(1)wherein &#x3bb; is a wavelength of the light beam, and n is a refractive index of the first protective film to a light having the wavelength &#x3bb;.

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 &#x3c3;/(&#x3bc;&#xd7;(2)) being 0.4 or less, wherein a noise power of a transmission path or a storage medium is &#x3c3;, a number of the encoded sub-information units is N, signal levels after amplitude modulation, which correspond to bitand bitof the encoded sub-information units, are A and B, and a level difference A&#x2212;B is &#x3bc;.

Signal processing system and information storage medium

According to one embodiment, there is provided an optical disk apparatus including a recording unit which irradiates an optical disk with a laser beam to record information in a first format and a second format, a generation unit which generates warning information to an optical disk apparatus capable of performing a read process in the second format while being not capable of performing the read process in the first format, the warning information warning that information is recorded in the first format in the optical disk, and a control unit which controls the recording unit to record the warning information in the second format in the optical disk apparatus when the information is recorded in the first format in the optical disk.

Optical disk apparatus and optical disk recording method with format warning information

A single disc is configured to deal with both HD DVD information and DVD information. This invention has the following basic elements (1) a single-sided dual layer optical disc where a light transmission layer, a first recording layer accessed with a first laser beam, an space layer, and a second recording layer accessed with a second laser beam are arranged in that order in the direction in which a laser beam enters, (2) the areal recoding density of the second recording layer is three times or more that of the first recording layer, (3) information indicating that the second recording layer has been formed is formed in the first recording layer, and (4) information indicating that the first recording layer has been formed is formed in the second recording layer.

Optical disc, optical disc apparatus, and optical disc reproducing method

Growing community of inventors

Yokohama, Japan

Hisashi Yamada