摘要:
An optical information recording medium including a first and second information layers is provided with an area where only the first information layer, which is provided nearer a substrate, exists, and initialization using a laser beam is started from this area. In an area where the second information layer exists, the first information layer is initialized after the second information layer is initialized. Alternatively, the first and second information layers are initialized at the same time by a flash light with adjusted emission time, emission energy, and the like. The first information layer is initialized after the second information layer is initialized by radiating a plurality of flash lights.
摘要:
A reflectance increasing type optical information recording medium in which the crosstalk is inhibited in the land and groove recording. This optical information recording medium comprises a substrate having a groove and a land provided between adjacent grooves and a recording layer that is provided on the substrate and that changes the reflectance by irradiation with light beams. In this recording medium, the reflectance after recording is greater than the reflectance before recording. Moreover, the depth D of the groove is set to be in the range of &lgr;/8n to 3&lgr;/8n, where the wavelength of the light beam is &lgr; and the refractive index of the substrate is n. And the difference, &Dgr;&phgr;=&phgr;1−&phgr;0, between the phase &phgr;1 of the reflected light after recording and the phase &phgr;0 of the reflected light before recording is in the range of (−0.1+2 m) &pgr; to (0.1+2 m) &pgr;, where m is an integer.
摘要:
The present invention provides an optical information recording medium of excellent signal quality in high density recording onto a semitransparent information layer, its manufacturing method and a manufacturing apparatus. The optical information recording medium of the present invention includes at least a semitransparent information layer disposed between a circular transparent substrate and a protective substrate, in which the information layer has spiral grooves for guiding a light beam, and also includes a recording film capable of recording/reproducing information thereon/therefrom by changing at least in two states detectable optically by irradiation of the light beam from the transparent substrate side, and the difference in film thickness of slope portions of the inner circumferential side and outer circumferential side of the groove is within ±10% in the entire region for recording/reproducing information.
摘要:
A multi-layer optical information recording medium has a first information layer located at the incident side for a laser beam and another information layer at the back thereof. Thus, it has a large capacity. A relationship that R1a
摘要:
An optical information recording medium is provided which has favorable signal quality even in high density recording using a translucent information layer. The optical information recording medium includes one or more information layers including a recording layer for recording/reproducing an information signal by irradiation with a laser light, and a separating layer or a protective substrate on which a first information layer of the information layer on the irradiation face side is formed, the separating layer or the protective substrate having a guide groove spirally or concentrically formed on the surface, and the respective inclined planes on the inner perimeter side and the outer perimeter side of the guide groove having inclined angles α and β with respect to the bottom face of the guide groove. The guide groove has one or more dissymmetric regions in the radius direction where the inclined angles α and β are different. The information layer has roughly agreeing thicknesses in the inclined face portion on the inner perimeter side and in the inclined face portion on the outer perimeter side in the dissymmetric region.
摘要:
Tracking control is carried out by a push-pull method or by mechanical feed at the time of recording signals, and tracking control is carried out by a phase difference tracking method at the time of reproduction. Thus, a phase change type optical disk which enables phase difference reproduction and is erasable may be realized. In a phase change type optical disk having a phase difference reproduction structure, servo mechanism at the time of reproducing signals may be stably controlled by causing the reflectance of a blank portion to be higher than the reflectance of a recording mark portion.
摘要:
An optical information recording medium provided with an information layer comprising at least Te, O and M atoms (wherein the M is at least one element selected from a metallic element, a metalloid element or a semiconductor element, most preferably Pd). The information layer comprises the O atoms in 40 atom %-60 atom %, the M atoms in 2 atom %-25 atom % and the Te atoms in 15 atom %-58 atom %, thus obtaining a preferable recording property having a high C/N ratio and a small jitter in a wide power margin in recording and reproducing information having a small b/d ratio (a ratio of a recording bit length b for a spot diameter d).
摘要:
The present invention provides an optical information recording medium of excellent signal quality in high density recording onto a semitransparent information layer, its manufacturing method and a manufacturing apparatus. The optical information recording medium of the present invention includes at least a semitransparent information layer disposed between a circular transparent substrate and a protective substrate, in which the information layer has spiral grooves for guiding a light beam, and also includes a recording film capable of recording/reproducing information thereon/therefrom by changing at least in two states detectable optically by irradiation of the light beam from the transparent substrate side, and the difference in film thickness of slope portions of the inner circumferential side and outer circumferential side of the groove is within ±10% in the entire region for recording/reproducing information.
摘要:
Tracking control is carried out by a push-pull method or by mechanical feed at the time of recording signals, and tracking control is carried out by a phase difference tracking method at the time of reproduction. Thus, a phase change type optical disk which enables phase difference reproduction and is erasable may be realized. In a phase change type optical disk having a phase difference reproduction structure, servo mechanism at the time of reproducing signals may be stably controlled by causing the reflectance of a blank portion to be higher than the reflectance of a recording mark portion.
摘要:
An optical information recording medium, wherein concave and convex shaped guide grooves narrower in width W than the spot diameter of the laser beam is formed in the face of the recording film layer of a substrate, and the recording film layer undergoes optically detectable changes caused by the application of a laser beam thereto, the detectable changes being due to the changes in the optical phase of the reflected light or the transmitted light, and the changes in the optical phase being caused in the direction of reducing the optical phase difference between concave and convex portions of guide grooves disposed in the substrate.