Abstract: An optical recording method to be used for recording at a high data transfer rate length-modulated marks on a recording medium by applying a recording laser beam locally to the recording medium. The recording laser beam has a writing power Pwi, is and a bias power Pbi. A record mark has a length of nT. With respect to at least two record marks, a pulse dividing number m is at least 2, and with respect to all record marks with m being at least 2, 2.5 is smaller than or equal to n/m, in a case where plural different record mark lengths are to be respectively formed by the same pulse dividing number m.

Abstract: The present invention provides a high level optical recording material which is capable of recording and reading by a blue laser with a short wavelength. An optical recording material comprises an organic dye compound A whose absorption maximum wavelength (?max) is not less than 340 nm and not more than 440 nm and a metal-complex compound B whose absorption maximum wavelength (?max) is not less than 500 nm and not more than 900 nm, the content of the organic dye compound A is higher than the content of the metal-complex compound B, and light resistance x determined by a predetermined method is not less than 30%.

Abstract: A rewritable optical recording medium includes a substrate and a phase-change type recording layer. A portion in a crystalline state corresponds to an unrecorded or erased state, and a portion in an amorphous state correspond to a recorded state, to record EFM modulated information by forming amorphous marks by irradiating the recording layer with a recording laser beam, and the recording is carried out by irradiating a recording laser beam having a wavelength of about 780 nm through an optical system having a numerical aperture NA of 0.5 or 0.55, at 24-times velocity or 32-times velocity of the reference velocity.

Abstract: An optical recording medium which comprises a print-receiving layer as the outermost layer on the side opposite to the light incidence side, wherein a pattern is formed on the print-receiving layer.

Abstract: The object of the present invention is to provide a technology which has high compatibility and can provide users with conveniences. A new system recording medium 100 has a center hole 112 formed on a recording disk 110 and a center hole 121 formed on a center hub 120, so that the recording medium 100 can respond to both an old system driving unit having a centering member coupling with the center hole 112 and a new system driving unit 300 having a second centering member 313 coupling with the center hole 121. Moreover, the old system recording medium is a recording medium providing a recording disk having a center hole incorporated in a cartridge having a center hub, and has a structure where the center hole is coupled both with a first centering member 312 of the new system driving unit 300 and with the centering member of the old system driving unit.

Abstract: An optical information-recording medium includes: a substrate; an electronic information-recording layer on the substrate in which digital information is recorded by the light applied from the side of the substrate; a reflection layer on the electronic information-recording layer; a visible information-recording layer on the reflection layer so that a region of the visible information-recording layer lays outside a circumference having a radius not less than half a radius of the substrate; and an over-coating on the visible information-recording layer. Visible information is recorded in the visible information-recording layer with light applied through the over-coating.

Abstract: The azo-metal chelate dye of the present invention is formed, for example, from zinc (divalent) as a center metal ion and an azo compound bonded with a coupler component having an amino group and a fluorine-substituted alkylsulfonylamino group subjected to condensed ring-formation to have a 1,3,4-thiazole ring as a diazo component.

Abstract: To obtain an optical information recording medium in a favorable initially crystallized state, by carrying out initial crystallization at a high linear velocity (specifically at least about 25 m/s), i.e. at a linear velocity higher than the erasable linear velocity for the optical information recording medium.

Abstract: A phase-change recording material used for an information recording medium utilizing a crystalline state as a non-recorded state and an amorphous state as a recorded state, which has the composition of the following formula (1) as the main component: (Sb1?xSnx)1?y?w?zGeyTewM1z??formula (1) wherein each of x, y, z and w represents atomicity, x, z and w are numbers which satisfy 0.01?x?0.5, 0?z?0.3 and 0?w?0.1, respectively, and the element M1 is at least one element selected from the group consisting of In, Ga, Pt, Pd, Ag, rare earth elements, Se, N, O, C, Zn, Si, Al, Bi, Ta, W, Nb and V, and (I) when z=0 and w=0, y is a number which satisfies 0.1?y?0.3, (II) when 0<z?0.3 and w=0, y is a number which satisfies 0.05?y?0.3, and (III) when 0?z?0.3 and 0<w?0.1, y is a number which satisfies 0.01?y?0.3.

Abstract: An optical recording medium which comprises a print-receiving layer as the outermost layer on the side opposite to the light incidence side, wherein a pattern is formed on the print-receiving layer.

Abstract: To provide an optical recording medium capable of high density recording or readout of optical information by a laser beam having a short wavelength. An optical recording medium comprising a substrate and a recording layer formed on the substrate, capable of recording or readout of information by irradiation with light, wherein the recording layer contains a 7-aminocarbostyril compound of the following formula (I): in the formula (I), X is an oxygen atom or a sulfur atom, R1 is a hydrogen atom or a linear or branched alkyl group which may be substituted, R6is a linear or branched alkyl group which may be substituted, and n=1 to 4.

Abstract: By use of a substrate which can be stably formed and has a relatively small groove depth, a very high density optical recording medium having good recording/reading characteristics is provided. In an optical recording medium of a surface incidence type, in which a reflective layer, a recording layer containing a dye as a main component and a cover layer are sequentially formed on a substrate having guide grooves formed therein, a guide groove part on a far side from a plane of incidence of a recording/reading light beam on the cover layer is set as a recording groove part, and reflected light intensity in a recorded pit portion formed in the recording groove part is increased by a phase shift and is set higher than reflected light intensity in unrecorded.

Abstract: A dual-layer optical recording medium, which is formed by adhering a disk substrate (inverted-stack structure) formed by stacking a reflective layer (1) and a recording layer (1) on a substrate (1) and a disk substrate (conventional-stack structure) formed by sequentially stacking a recording layer (2) and a reflective layer (2) on a transparent substrate (2) with a transparent resin layer interposed therebetween, is prepared such that the transparent resin layer has a product obtained by multiplying the thickness by the elastic modulus at 25±5° C. falling within the range of not less than 2.0×104 MPa·?m to not more than 30.0×104 MPa·?m, resulting in suppressing excessive deformation involving an adjacent track portion produced by recording optical information in the recording layer (1) of the inverted-stack structure, thereby reducing crosstalk and providing satisfactory recording and/or reading characteristics in high-speed recording applications.

Abstract: Disclosed herein is a Hybrid Coaxial Fiber (HCF) network-based high-speed Quality of Service (QoS) transmission system for IP broadcasting service. In the system, a L3 switch unit, a CMTS and a coupler are provided on an ISP side, and an optical distributor, a cable modem, and IP set-top box are provided on an Internet service subscriber side. The transmission system includes one or more IP-QAM transmitters and an IP-QAM modem. The IP-QAM transmitters are connected between the L3 switch unit and coupler on the ISP side in parallel with the CMTS, and modulate the phases and amplitudes of IP broadcasting service data transmission signals into carrier signals different from Internet service data transmission signals and cable TV signals. The IP-QAM modem is connected to the coupler in parallel with the cable modem, and demodulates the IP broadcasting service data and transfer the demodulated IP broadcasting service data to the IP set-top box.

Abstract: In an optical recording medium having two recording layers of a first recording layer and a second recording layer, the second recording layer contains metallized azo dyes represented by the following general formula (I) or (II), and recording characteristics of the second recording layer are improved by having optical density of 1.3 times as large as, or 1.3 times greater than, that of a dye contained in the first recording layer. (In this regard, rings A1 and A2 are nitrogen-containing heteroaromatic rings, rings B1 and B2 are aromatic rings, and X is alkyl group substituted by at least two fluorine atoms.

Abstract: An optical recording method for recording mark length-modulated information on a recording medium by using a plurality of recording mark lengths. The optical recording method comprises the steps of: when a time length of one recording mark is denoted nT (T is a reference clock period equal to or less than 25 ns, and n is a natural number equal to or more than 2), (i) dividing the time length of the recording mark nT into ?1T, ?1T, ?1T, ?2T, ?2T, . . . , ?iT, ?iT, . . .

Abstract: A phase-change recording material on which high speed recording/erasing is possible, which has excellent recording characteristics, which has a high storage stability of recording signals and which is excellent in the repeated recording durability, and an information recording medium using the above material are provided. A phase-change recording material characterized by containing as the main component a composition represented by {(Sb1?xGex)1?yIny}1?z?wMzTew wherein x, y, z and w are numbers satisfying 0.001?x?0.3, 0?y?0.4, 0?z?0.2 and 0?w?0.1, and M is at least one element selected from lanthanoids, provided that z and w are not 0 at the same time.

Abstract: An optical recording medium which comprises a print-receiving layer as the outermost layer on the side opposite to the light incidence side, wherein a pattern is formed on the print-receiving layer.

Abstract: Provided is an optical recording method for recoding information on a phase-change optical recording medium at a low linear velocity by use of a divided pulse method. When forming a plurality of recording marks by use of a constant divided pulse number m, a light irradiation time period of recording light for recording a recording mark having a time length of nT is divided in the order of {?1T, ?1T, ?2T, ?2T, . . . , ?iT, ?iT, . . . , ?mT, ?mT} (in which m is a natural number representing a divided pulse number, ?i (1?i?m) is a real number greater than 0, ?i (1?i?m?1) is a real number greater than 0, and ?m is a real number equal to or above 0).