Sony Corporation

Toppan Printing Co., Ltd.

Sony Corporationn

Sony Corporation and Sony Disc Technology Inc.

Toshiyuki Kashiwagi

Takeshi Yamasaki

Motohiro Furuki

Tomomi Yukumoto

Masanobu Yamamoto

Hisayuki Yamatsu

Shingo Imanishi

Yuji Akiyama

Nobuyuki Arakawa

Hiroshi Ohki

Seiji Kobayashi

Tetsuhiro Sakamoto

Shin Masuhara

Masahiko Kaneko

Hiroshige Okamura

Osamu Kawakubo

Yoshiaki Kato

Minoru Takeda

Koichi Yasuda

Masato Nishida

Hiroshi Ogawa

Katsuhisa Aratani

Kimihiro Saito

Kiyoshi Ohsato

Daisuke Ueda

Akiya Saito

Akihiko Kobayashi

Takao Kondo

Kiyoshi Osato

Ariyoshi Nakaoki

Yuichi Aki

Hiroshi Iwase

Minoru Kikuchi

Yoshitake Yanagisawa

Noboru Sasaki

Mamoru Sekiguchi

Shinsuke Kishi

Yoshimori Yamasaki

Yoshihiro Akimoto

Ken Minemura

Mitsuo Naito

Eijiro Kikuno

Toshiro Kinoshita

Makoto Arisawa

Hiroshi Ooki

Kohtaroh Kurokawa

Asao Kurosu

Shoji Fukuchi

An optical recording medium and a manufacturing method for forming the optical recording medium is provided. The optical recording medium includes a bar code-shaped reflection pattern that includes high reflection rate regions and low reflection rate regions and information is recorded with the bar code-shaped reflection pattern. The low reflection rate region is formed with pit strings. The high reflection rate region and the low reflection rate region are formed to satisfy: S+M/2&#x2266;0.6H, where a signal level of a reproduction signal obtained from a reflection light in the high reflection rate region is denoted as 'H', a signal level of a reproduction signal obtained from a reflection light in the low reflection rate region is denoted as 'S', and a degree of modulation of the reproduction signal obtained from the reflection light in the low reflection rate region is denoted as &#x201c;M&#x201d;.

Optical recording medium, manufacturing method for optical recording medium

The present invention relates to an optical disc for use as a recording medium in an optical disc drive, which has a transparent protection film () formed on a recording layer on one plane of the disc substrate () and a printing label filmbeing of approximately the same film quality and film structure as the transparent protection film () formed on the other plane thereof. The printing label film () is a synthetic resin film made mainly of polycarbonate and formed on the disc substrate by screen printing, etc. Thus, the optical disc has the same film quality and film structure on the respective one and the other planes, which prevents occurrence of skew caused by the deformation due to the asymmetry of the structure along the thickness direction of the optical disc. The optical disc has a function to present contents of information recorded therein with the printing label film provided on the other plane of the disc substrate.

Optical disk

An optical disk () of the present invention has a substrate () included a resin-impregnated paper, in which resin is impregnated into paper, or resin-coated paper, in which the paper surface is coated with a resin, and a recording layer () formed on at least one side of the substrate (). This type of optical disk () has performance equal to that of conventional optical disks and has a minimal effect on the environment during disposal. In addition, a manufacturing method of an optical disk of the present invention has a recording layer sheet fabrication step in which a recording layer sheet is fabricated by forming tracks on a recording layer base material, and a recording layer sheet lamination step in which a recording layer () included the recording layer sheet is provided on a substrate () included resin-impregnated paper or resin-coated paper by laminating the recording layer sheet with the resin-impregnated paper in which a resin is impregnated into paper or the resin-coated paper in which the surface of the paper is coated with a resin. This type of manufacturing method of an optical disk allows optical disk () to be produced inexpensively.

Optical disk and its manufacturing method

An optical recording medium capable of suppressing warps arising during a long time use and a method of producing the same, which has the configuration of comprising a substrate, an optical recording layerformed on the substrateand a light transmitting protective filmformed on the optical recording layer, wherein the protective filmincludes a polymer filmhaving a thermal shrinkage coefficient of 0.02% or less and an adhesive layerfor adhering the polymer filmto the optical recording layer. As the polymer film, those produced by a melt cast method, subjected to annealing processing in advance or having a residual solvent of 0.3% by weight or less in the film may be preferably used.

Optical recording medium and method of producing the same

The present invention provides an optical disc which is constituted by a substrate, a recording layer, and a protection layer and is irradiated with a laser beam from the protection layer side. The optical disc has the substrate whose diameter is greater than 50 mm, the recording layer provided on the substrate, and the protection layer which is layered on the recording layer and thinner than the substrate and on which a recording or reproducing laser beam is incident. The total thickness of the optical disc is 0.7 mm or more.

An electron beam irradiation apparatus, includes a support section for supporting an electron beam irradiation subject to be irradiated with an electron beam, and an electron beam irradiation head opposed to the electron beam irradiation subject via a minute space, the electron beam irradiation head having an electron beam emission hole for irradiating the electron beam irradiation subject with the electron beam. In the electron beam irradiation head, an electron beam path communicating with the electron beam emission hole is provided, and in addition one or more ring shaped gas suction grooves opened from a surface of the electron beam irradiation head facing the electron beam irradiation subject is formed around the electron beam emission hole. Vacuum pumps are coupled to the electron beam path and the ring shaped gas suction grooves, and the electron beam path is held in a high vacuum state.

Electron beam irradiation apparatus, electron beam irradiation method, original disk, stamper, and recording medium

An optical recording medium capable of improving uniformity of thickness of a protective film and suppressing warping. The medium is configured to include a substrate, an optical recording film formed on the substrate, and a light transmitting protective film formed above the optical recording layer, wherein the protective film includes a polymer sheet produced by melt casting and an adhesive layer for bonding the polymer sheet to the optical recording layer. As the polymer sheet, a polycarbonate sheet, a cyclic polyolefin sheet, etc. can be used. As the adhesive layer, an ultraviolet curing resin, a heat curing resin, an epoxy resin-based adhesive agent or a pressure-sensitive tackiness agent may be used alone or mixed or stacked.

Method of producing an optical recording medium

Optical recording medium

A recording medium for information signals including a substrate, a signal recording layer provided on one major surface of the substrate and a clamp member having a positioning unit at its center portion and formed of a material that can be magnetically attracted by a magnet. The clamp member is unified to the center portion of the substrate so that the surface of the clamp member will be flush with the substrate surface.

Disk-like recording medium and method for producing the same

The present invention relates to a multi-layered disc-shaped information recording medium having a plurality of signal recording layers each carrying information signals. In preparing the recording medium, a first substrate obtained on punching a sheet obtained in turn by having a signal recording pattern transcribed on it from a first stamper and by forming a semi-transparent film on a signal surface is bonded to a second substrate obtained on injection molding a synthetic resin material. The second substrate is prepared by having transcribed to it a signal recording pattern formed on a second stamper provided on an injection molding device. A reflective film is formed on a signal surface having the transcribed second substrate. The first and second substrates are bonded together on their signal recording layers by a transparent adherent layer.

Disk-like multilayer information recording medium and production method thereof

An optical disc includes a substrate, and a recording layer and transparent layer formed in this order on the substrate. A light is incident from the transparent layer to write and/or read an information signal. The substrate comprises a first resin layer forming a surface of the substrate on which the recording layer is formed, and a second resin layer having a higher flexural modulus is formed on the first resin layer.

Optical recording medium with a substrate of two different resin layers

An optical disc and its manufacturing method in which humps may be prohibited from being formed on an outer rim area of the disc to assure optimum surface properties of a light transmitting layer of the disc to contribute to further increase in recording capacity. On a substrate of an optical disc are sequentially formed a recording portion and a light transmitting layer . The light falls on the light transmitting layer to record and/or reproduce information signals for a signal recording area of the substrate . The radial distance D from the outermost rim of the substrate to the signal recording area is selected to be larger than the radial width L of a hump formed on the outer rim of the light transmitting layer . The hump has a height h from the surface of the light transmitting layer not larger than 70 &mgr;m.

Optical disc and method for manufacturing same

An optical disk has a groove formed in the direction of a recording track and a first information signal is recorded by forming a row of marks or dots on the groove or land. A second information signal can also be recorded on the groove or land without adversely affecting the playback characteristic of the first information signal. A groove is formed in the direction of the recording track and a row of marks or dots corresponding to the first information signal is formed on the groove or land, so that the first information signal can be recorded. Further, by forming a wave having a spatial frequency higher than a cut-off frequency of a playback optical system corresponding to a second information signal on a part or all of the groove, the second information signal is recorded. The second information signal can represent visible information.

Optical disk with information signal representing a character, method and apparatus

A method of production of a multilayer optical recording medium capable of avoiding difficulties in separating a stamper and forming a semi-transparent film on a thin flexible film and a production method thereof, comprising steps of forming a first optical recording layer on a substrate formed with a pattern of irregularities for a first optical recording layer on a surface thereof, forming a transfer substrate comprised of an acrylic resin formed with a pattern of irregularities on a surface thereof, forming a second optical recording layer on the pattern of irregularities of the transfer substrate, adhering a flexible film at the upper portion of the second optical recording layer by an adhesive layer, separating the second optical recording layer and the transfer substrate at their boundary to transfer the second optical recording layer to the flexible film, and bonding together the first optical recording layer and the second optical recording layer with them facing each other.

Method of production of multilayer optical recording medium

Growing community of inventors

Tokyo, Japan

Toshiyuki Kashiwagi