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: 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: 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 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: 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: An optical recording medium including a substrate, a bottom protective layer located overlying the substrate, an optical recording layer located overlying the bottom protective layer, a top protective layer located overlying the optical recording layer, an intermediate layer located overlying the top protective layer, comprising at least one element (M) selected from the group consisting of Ti, Nb and Ta, and carbon, an optical reflective layer comprising Ag in an amount not less than 95 atomic %, located overlying the intermediate layer. The optical recording medium is recordable even in at least one of the following recording conditions (1) to (3): (1) when a recording time for a shortest recording mark is not greater than 34 ns; (2) when a recording time of a channel bit length is not greater than 11 ns; and (3) when a recording linear velocity is not less than 11 m/s.

Abstract: An initialization method in which a phase change optical recording medium is initialized with a laser beam having a power density of from 15 to 22 mW/&mgr;M2 at a linear velocity of from 8 to 12 m/s. The phase change optical recording medium is formed of a transparent substrate having a guide groove on the surface thereof, a first protective layer, a recording layer, a second protective layer and a reflective layer. The recording layer material may be represented by the following composition formula: Ag&agr;X&bgr;Sb&dgr;Te&egr;Ge&ggr;, wherein X is at least one of Ga, In, Tl, Pb, Sn, Bi, Cd, Hg, Mn, Dy, Cu and Au, and &agr;, &bgr;, &dgr;, &egr;, and &ggr; have units of atomic % and satisfy particular relationships.

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.