Abstract: An optical recording medium containing a substrate and a recording layer over the substrate, wherein the recording layer primarily contains Bi and O, and further contains B and at least one element X selected from Ge, Li, Sn, Cu, Fe, Pd, Zn, Mg, Nd, Mn and Ni, and a sputtering target containing Bi, B and at least one element X selected from Ge, Li, Sn, Cu, Fe, Pd, Zn, Mg, Nd, Mn and Ni.

Abstract: A dual-layer structure phase-change type optical recording medium includes a substrate (1), a reflective layer (2), a first protective layer (3), a first recording layer (4), a second protective layer (5), a resin intermediate layer (6), a third protective layer (7), a heat release layer (8) made of Cu or a Cu alloy, a fourth protective layer (9), a second recording layer (10), a fifth protective layer (11) and a cover substrate (12). A product of a reflectance of a high-reflection part and a modulation after recording is a value equal to or higher than a lower limit value for reproduction.

Abstract: A method of recording information using a laser on a multilayer optical disk having a plurality of recording layers is provided. The plurality of recording layers include a first recording layer and a second recording layer adjacent the first recording layer. The first recording layer is provided with a first test writing area to be used for calibration of write power, and the second recording layer is provided with a second test writing area to be used for calibration of write power. The disk is arranged so that a first region of the first test writing area is superposed with a second region of the second test writing area when considered in the direction in which the laser is arranged to irradiate.

Abstract: A power determining method is disclosed for determining the light emitting power of a light source upon recording information on an optical disk having plural rewritable recording layers, the method involving obtaining an optimum erasing power with respect to an optimum recording power by recording test data on the optical disk.

Abstract: The present invention relates to an recording method for a multi-layered optical recording medium including M phase change recording layers, with M?2. The method comprises recording a mark in a Kth one of said recording layers by using a laser to irradiate the Kth recording layer using a recording pulse train including a plurality of laser beam pulses. The recording pulse train for the Kth recording layer has a cycle of t(K)[T], the 1st recording layer is the recording layer closest the laser beam, and the Mth recording layer is the recording layer furthest from the laser beam, T is a clock cycle. The following relationship is satisfied: t(1)<t(M), and the cycle of recording pulse train does not decrease from one recording layer to the next recording layer in the direction in which the laser beam irradiates.

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 recording medium containing a substrate and a recording layer over the substrate, wherein the recording layer primarily contains Bi and O, and further contains B and at least one element X selected from Ge, Li, Sn, Cu, Fe, Pd, Zn, Mg, Nd, Mn and Ni, and a sputtering target containing Bi, B and at least one element X selected from Ge, Li, Sn, Cu, Fe, Pd, Zn, Mg, Nd, Mn and Ni.

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: A recordable optical information recording medium having an address t for each sector, comprises: an area A1 starting from an address t1 to which access is made only when a recording apparatus performs recording operation; an area A2 starting from an address t2 to which access is made either when the recording apparatus performs the recording operation or when the recording apparatus performs reproducing operation; and an area A3 starting from an address t3 to which access is made either when either the recording apparatus or a reproducing apparatus performs recording or when either the recording apparatus or the reproducing apparatus performs reproducing. The addresses t are set consecutively with respect to a physical arrangement of the sectors in each of the areas A2 and A3, and the area A1 has at least one inconsecutive part at which the addresses t are not consecutive with respect to the physical arrangement of the sectors.

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 recording medium includes at least a supporting substrate and a recording layer essentially consisting of AgInSbTe alloy compositions implementing recording and readout steps utilizing changes in reflectivity. The recording medium is characterized by the relation v0?0.7 vWH, where the critical relative velocity of phase change, v0, defined by the value of v, at which the differential coefficient, ?dR(v)/dv, reaches a maximum, when the recording medium moves against an optical unit during the recording steps at a relative velocity, v, ranging from minimum and maximum relative velocities warranted for the recording medium, vWL and vWH, respectively. When the reflectivity is measured with varying erase power PE at the linear relative scanning velocity v0, the reflectivity of the recording layer as a function of erase power, R(PE), preferably has a minimum. The recording layer has an activation energy of deterioration equal to or greater than 1.

Abstract: A method and apparatus for initializing optical recording media is provided that detects the intensity of a reflective light off of an optical recording media and analyzes the initializing condition based on the detected intensity during an initializing process. The light is radiated on a rotating phase-change optical recording medium. The light may be moved in a radial direction of the optical recording medium. The detected intensity of the reflected light may be used to identify crystallized portions and amorphous portions of the optical media. The initialization process can be adaptively controlled to ensure proper initialization. If desired, re-initialization can be limited to those areas detected to be outside of the predetermined parameters.

Abstract: A recordable optical information recording medium having an address t for each sector, comprises: an area A1 starting from an address t1 to which access is made only when a recording apparatus performs recording operation; an area A2 starting from an address t2 to which access is made either when the recording apparatus performs the recording operation or when the recording apparatus performs reproducing operation; and an area A3 starting from an address t3 to which access is made either when either the recording apparatus or a reproducing apparatus performs recording or when either the recording apparatus or the reproducing apparatus performs reproducing. The addresses t are set consecutively with respect to a physical arrangement of the sectors in each of the areas A2 and A3, and the area A1 has at least one inconsecutive part at which the addresses t are not consecutive with respect to the physical arrangement of the sectors.

Abstract: A phase-change optical recording medium is disclosed including a supporting substrate and the following contiguous layers formed on the supporting substrate in the order recited such as a first dielectric layer, a recording layer, a second dielectric layer, a metal/alloy layer, and an ultraviolet light curing resinous layer. The recording layer is characterized by its uppermost recrystallization linear velocity ranging from about 5.0 m/sec to about 10.0 m/sec, which can be utilized in read/write/erase operations for the recording medium at linear velocities higher than the quad-speed as well.

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: A power determining method is disclosed for determining the light emitting power of a light source upon recording information on an optical disk having plural rewritable recording layers, the method involving obtaining an optimum erasing power with respect to an optimum recording power by recording test data on the optical disk.