Abstract: There is provided an optical information recording medium including a plurality of laminated resin layers, and an inorganic layer that is formed in an interface between the resin layers. Storage elastic moduli are different when the interface is assumed to be a boundary. An information signal is recorded in the interface.

Abstract: To provide a sputtering target for preparing a recordable optical recording medium characterized by comprising Bi and B and a manufacturing method thereof, a recordable high density optical recording medium using the sputtering target, and a sputtering target which is capable of improving a speed of the film formation for the improvement of productivity, which has a high intensity at the time of the film formation and which has a heightened packing density.

Abstract: To provide a sputtering target for preparing a recordable optical recording medium characterized by comprising Bi and B and a manufacturing method thereof, a recordable high density optical recording medium using the sputtering target, and a sputtering target which is capable of improving a speed of the film formation for the improvement of productivity, which has a high intensity at the time of the film formation and which has a heightened packing density.

Abstract: To provide a sputtering target for preparing a recordable optical recording medium characterized by comprising Bi and B and a manufacturing method thereof, a recordable high density optical recording medium using the sputtering target, and a sputtering target which is capable of improving a speed of the film formation for the improvement of productivity, which has a high intensity at the time of the film formation and which has a heightened packing density.

Abstract: Provided is a recordable optical recording medium that comprises a substrate, a recording layer, and a reflective layer, wherein the recording layer and the reflective layer are formed on the substrate, the recording layer is formed of an inorganic material, and information is recorded on the recordable optical recording medium by use of an irreversible change at the recording layer caused by irradiating blue laser light.

Abstract: A recording method including: recording on a write-once-read-many optical medium capable of recording and reproducing with a blue laser by CAV, ZCLV, or PCAV, wherein a laser emission pattern including a recording pulse comprises two or more different levels of recording power, and a laser emission time standardized by the laser emission pattern and reference clock is fixed regardless of a recording linear velocity.

Abstract: An optical disc having a transition linear velocity of 8-11 m/s when irradiating continuous light with 11±1 mW and a wavelength of 660±10 nm using a pickup head with a numerical aperture (NA) of 0.65, and satisfying the following condition: ?R=|Rb?Ra|?3% where Rb is a reflectance of an unrecorded area, and Ra is a reflectance of the top of an eye pattern after ten cycles of recording. In one recording mode therefor, the disc is rotated at a constant angular velocity so as to have a linear velocity of 3-4 m/s on an innermost track and a linear velocity of 8-9 m/s on an outermost track. In another mode, the disc is rotated at a constant angular velocity so as to have a linear velocity of 5-6 m/s on an innermost track and a linear velocity of 13-14 m/s on an outermost track.

Abstract: The object is to provide an optical recording method improving the recording characteristics and uniformity in a CAV recording on a phase-change optical recording medium, particularly a high-speed rewritable DVD medium, and a phase-change optical recording medium and an optical recording apparatus used by the method.

Abstract: An optical information recording medium is provided. This medium at least stores information that indicates a maximum recording linear velocity Vh. The medium comprises a substrate having a concentric circular guide groove. This guide grove has land portions and groves portions. At least a phase change type recording layer is formed on the substrate. The recording layer has such a composition and thickness that a dislocation linear velocity V satisfies the relation V?Vh×0.85.

Abstract: There is provided a method and a device for recording optical data able to improve recording power setting during recording by means of PWM with a small number of pulses. During the test recording, using a period of a recording channel clock Tw as the minimum unit, marks having different mark lengths of n1·Tw and n2·Tw (n1<n2) are recorded with the same number of m (m<n) light emitting pulses, while successively changing the maximum power Pw of the recording signals. The recorded marks are reproduced and the mark lengths T1 and T2 are measured from the reproduced signals. The recording power can be set by evaluating the deviations D1=T1?n1·Tw and D2=T2?n2·Tw.

Abstract: A phase-change optical information recording medium in which information can be recorded, reproduced and rewritten and which includes a first transparent substrate having a wobbling guide groove which is spirally formed thereon at a pitch; a first dielectric layer located overlying the first transparent substrate and having an optical thickness of from 80 nm to 200 nm; a phase-change recording layer located overlying the first dielectric layer and having an optical thickness of from 20 to 50 nm when the recording layer is in an erased state; a second dielectric layer located overlying the recording layer and having an optical thickness of from 10 nm to 70 nm; a reflection layer located overlying the second dielectric layer; optionally a third dielectric layer located between the second dielectric layer and the reflection layer; and a second transparent substrate located overlying the reflection layer.

Abstract: A phase-change optical information recording medium in which information can be recorded, reproduced and rewritten and which includes a first transparent substrate having a wobbling guide groove which is spirally formed thereon at a pitch; a first dielectric layer located overlying the first transparent substrate and having an optical thickness of from 80 nm to 200 nm; a phase-change recording layer located overlying the first dielectric layer and having an optical thickness of from 20 to 50 nm when the recording layer is in an erased state; a second dielectric layer located overlying the recording layer and having an optical thickness of from 10 nm to 70 nm; a reflection layer located overlying the second dielectric layer; optionally a third dielectric layer located between the second dielectric layer and the reflection layer; and a second transparent substrate located overlying the reflection layer.

Abstract: An optical information recording medium including a substrate, a light absorbing layer which is located overlying the substrate and in which marks are formed to store information and a light reflection layer located overlying the light absorbing layer including a crystal, wherein the optical information recording medium satisfies the relationship, Lt/4 ?Lc? Lm, wherein Lc represents the average particle diameter of the crystal of the light reflection layer, Lm represents the minimum length of the marks, and Lt represents the thickness of the light reflection layer.

Abstract: An information recording method including irradiating an optical information recording medium containing a phase change recording layer on a substrate having a guide groove with continuous light of a laser beam having an erase power level Pe to determine a transition linear velocity Vo defined as a minimum linear velocity above which the following relationship is satisfied: Rr=Ra/Rb<1, wherein Rr represents a reflection light intensity ratio, and Ra and Rb represent a reflection light intensity measured after and before the irradiation of the optical information recording medium with the continuous light, respectively, prior to recording information in the optical information recording medium.

Abstract: To provide a dual-layer recordable optical recording medium, including: a first information layer; intermediate layer disposed over the first information layer; and second information layer disposed over the intermediate layer, the first information layer, intermediate layer, and second information layer being sequentially deposited from a laser irradiation side, wherein the first information layer comprises, from the laser irradiation side, at least a thin film containing Bi as a main ingredient, dielectric layer, reflective layer and thermal diffusion layer, and the second information layer comprises, from the laser irradiation side, at least a thin film containing Bi as a main ingredient, dielectric layer and reflective layer, and wherein the ratio of the thickness of the dielectric layer of the second information layer (t2) to the thickness of the dielectric layer of the first information layer (t1), t2/t1, is in a range of 0.7 to 1.5 or 4.5 to 6.0.

Abstract: To provide a sputtering target for preparing a recordable optical recording medium characterized by comprising Bi and B and a manufacturing method thereof, a recordable high density optical recording medium using the sputtering target, and a sputtering target which is capable of improving a speed of the film formation for the improvement of productivity, which has a high intensity at the time of the film formation and which has a heightened packing density.

Abstract: An optical recording medium including a substrate having guide groove thereon; a first protective layer located overlying the substrate; a recording layer located overlying the first protective layer; a second protective layer located overlying the recording layer; a third protective layer of from 2 to 9 nm thick located overlying the second protective layer and comprising Si in an amount not less than 35 atomic percent; and a reflection layer including Ag in an amount not less than 95% by weight. An overcoat layer having a glass transition temperature of from 90° C. to 180° C. is preferably formed overlying the reflection layer. A method for manufacturing the optical recording medium is also provided.

Abstract: To provide a sputtering target used for the formation of a recording layer of a recordable optical recording medium, wherein the sputtering target contains Bi and Fe and the packing density of the sputtering target is greater than 96%, and a recordable optical recording medium manufactured by using the sputtering target, which the recordable optical recording medium is capable of high-density recording even in the blue laser's wavelength range.

Abstract: An object of the present invention is to provide an optical recording medium which exhibits high storage reliability in high-temperature/high-humidity conditions, stable performance at high temperatures, appropriate mechanical properties and high productivity and is capable of reproducing and recording at high speeds. It is an optical recording medium containing a lower protective layer, an optical recording layer, an upper protective layer and an optical reflective layer which contains 98% by weight or more of Ag that are formed on the substrate, the thickness of the optical recording layer is 8 nm to 14 nm and the thickness of the upper protective layer is 4 nm to 24 nm, the upper protective layer contains at least one of zinc oxide, indium oxide, tin oxide, niobium oxide, silicon nitride, aluminum nitride and SiOx (1.6?x?1.9) and less than 0.1% by weight of at least any one of sulfur and chlorine, and the upper protective layer is amorphous after recording or rewriting.

Abstract: A phase change optical information-recording medium includes a substrate, a bottom protection layer, a recordation layer, a top protection layer, and a reflection layer, each formed on the substrate in that order. The reflection layer mainly includes Ag, and the top protection layer mainly includes oxide and nitride or carbide.