Abstract: An information recording medium for high-density recording and reproduction that is low-cost and that has good rewrite characteristics. The information recording medium, in which recording is performed as an atomic arrangement is changed by optical irradiation, is capable of a number of rewrites. The information recording medium comprises a substrate on which a first protective layer with a thickness in the range from 18 to 65 nm, a recording film, a second protective layer, and a reflective layer are disposed in the mentioned order as seen from a light-incident side. Not less than 97 atomic % of the composition of the recording film is accounted for by Ge, Bi, and Te.

Abstract: An information recording medium comprising a plurality of layers for recording or reproduction of information by optical irradiation. Each of the layers of the recording medium includes asperities made up of a groove, wherein the groove in each of the layers has wobbles of a first frequency and wobbles of a second frequency that is different from the first frequency within a single track. The first frequency is constant in each of the layers, and a different signal is obtained from the wobbles of the first and second frequencies in each of the plurality of layers.

Abstract: In an information recording medium, a first protective layer, a recording film, a second protective layer and a reflective layer are provided on a substrate sequentially from a side where light is irradiated, the first protective layer having a film thickness of 2 nm to 25 nm. 95 atomic % or more of a material of the first protective layer is SiO2—In2O3—SnO2—ZnS, and a ZnS amount in the first protective layer is in the range of 4 mol % to 33 mol %.

Abstract: A method of recording information by irradiating a recording track in an information recording medium with light, the information recording medium comprising a plurality of layers for the recording of information by light irradiation. Each of the layers comprises asperities made up of a groove, the groove in each of the multiple layers having wobbles of a first frequency and wobbles of a second frequency that is different from the first frequency within a single track, wherein the first frequency is constant in each of the layers, and wherein a different signal is obtained from the wobbles of the first and second frequencies in each of the plurality of layers.

Abstract: A method for recording information is disclosed in which an information recording medium is irradiated with a recording energy beam power-modulated into at least a record power level and a record-ready power level lower than the record power level. When forming a mark portion of a predetermined length, the radiation energy of the energy beam is increased as compared with when forming a mark portion of a different length before or after the first pulse of an energy beam pulse train including at least a pulse for forming the mark portion. Also, only in the case where the energy beam is modulated by the power lower in power level than the record-ready power level after the last pulse of the energy beam pulse train including at least one pulse for forming a mark portion and the mark portion is followed by a space portion of a predetermined length, the particular radiation energy of low power level is reduced as compared with when the mark portion is followed by a space potion of a different length.

Abstract: An information recording medium having a substrate, a recording layer on which information is recorded in accordance with a change of atomic arrangement caused by irradiation of light, a first reflective layer, and a second reflective layer. The second reflective layer is formed on the first reflective layer. The first reflective layer includes an Al alloy as a main component and the second reflective layer includes an Ag alloy as a main component.

Abstract: A method for recording information is disclosed in which an information recording medium is irradiated with a recording energy beam power-modulated into at least a record power level and a record-ready power level lower than the record power level. When forming a mark portion of a predetermined length, the radiation energy of the energy beam is increased as compared with when forming a mark portion of a different length before or after the first pulse of an energy beam pulse train including at least a pulse for forming the mark portion. Also, only in the case where the energy beam is modulated by the power lower in power level than the record-ready power level after the last pulse of the energy beam pulse train including at least one pulse for forming a mark portion and the mark portion is followed by a space portion of a predetermined length, the particular radiation energy of low power level is reduced as compared with when the mark portion is followed by a space potion of a different length.

Abstract: To provide an information recording medium which permits high density recording/reproduction, which has good thermal stability, and which, due to the use of an interface layer with a high sputter rate, has good recording/reproduction characteristics and is excellent for mass production. An information recording medium wherein the thickness of an interface layer 3 is 0.25 or more but 0.67 or less of the total thickness of a first protective layer 2 and the interface layer 3, and the interface layer 3 contains at least tantalum (Ta) and oxygen (O). The medium is excellent for mass production and has good recording/reproduction characteristics for high density recording/reproduction.

Abstract: A multi-time rewritable information recording medium conducting writing by the change of arrangement of atoms under the irradiation of light, comprising, from the light-incident side, a substrate of a thickness of 0.7 mm or less, a lower protective layer of a thickness of 20 nm to 60 nm, a recording film, an upper protective layer, and a reflective layer, wherein the interval between tracks is 0.62 &mgr;m or less. The medium can also possess favorable writing/reading characteristics at high density writing/reading, have large processing margin, use a manufacturing apparatus at a reduced cost, cut material cost, and realize mass productivity with less stresses.

Abstract: This invention relates to an information-recording medium that is used for recording information through radiation of energy beam. The information recording medium has a groove-shaped information recording track and is provided with a recording layer, one or more kinds of heat sink control layers and heat sink layers. A sum of film thickness of the more than one kind of recording layer is equal to or less than a step between information recording tracks, and a sum of film thickness of one or more kinds of heat sink control layers is more than a groove depth of the information recording track. With this configuration, no cross-erase is produced even if the information-recording medium is applied for a high density recording with the track pitch being 70% or less.

Abstract: A recording medium having a dummy signal area on at least one side of a recording area is used and information is recorded with a dummy signal added to at least one of the leading and trailing sides in the recorded information signal. The user data area remains unaffected by repeated overwriting so that recorded user data is reproduced correctly. In particular, the wave form distortion caused by fluidization of a recording film remains at the dummy signal area and does not affect the user data area, so that the reproduction of the target information (user data) is assured.

Abstract: In an information recording medium, a first protective layer, a recording film, a second protective layer and a reflective layer are provided on a substrate sequentially from a side where light is irradiated, the first protective layer having a film thickness of 2 nm to 25 nm. 95 atomic % or more of a material of the first protective layer is SiO2—In2O3—SnO2—ZnS, and a ZnS amount in the first protective layer is in the range of 4 mol % to 33 mol %.

Abstract: A recording medium having a dummy signal area on at least one side of a recording area is used and information is recorded with a dummy signal added to at least one of the leading and trailing sides in the recorded information signal. The user data area remains unaffected by repeated overwriting so that recorded user data is reproduced correctly. In particular, the wave form distortion caused by fluidization of a recording film remains at the dummy signal area and does not affect the user data area, so that the reproduction of the target information (user data) is assured.

Abstract: This invention relates to an information-recording medium that is used for recording information through radiation of energy beam. The information recording medium has a groove-shaped information recording track and is provided with a recording layer, one or more kinds of heat sink control layers and heat sink layers. A sum of film thickness of the more than one kind of recording layer is equal to or less than a step between information recording tracks, and a sum of film thickness of one or more kinds of heat sink control layers is more than a groove depth of the information recording track. With this configuration, no cross-erase is produced even if the information-recording medium is applied for a high density recording with the track pitch being 70% or less.

Abstract: Problem to be solved is that when an information recording medium is repeatedly subjected to recording of information several hundreds times, the atoms in a protective layer are diffused and dissolved into a recording layer to lower a reflectivity greatly and make the medium unendurable to many times of overwriting. This problem can be solved by a medium constituted of interference layer 10, interface layer 12, phase-change type recording layer 14, protective layer 13 having a tin content of from 23.3 atomic % to 32.3 atomic %, and a heat sink layer 8 successively formed on substrate 1, as seen from a light-incidence side. By use of this medium, the dissolution of atoms can be prevented, and overwriting for many times can be achieved.

Abstract: A method for recording information is disclosed in which an information recording medium is irradiated with a recording energy beam power-modulated into at least a record power level and a record-ready power level lower than the record power level. When forming a mark portion of a predetermined length, the radiation energy of the energy beam is increased as compared with when forming a mark portion of a different length before or after the first pulse of an energy beam pulse train including at least a pulse for forming the mark portion. Also, only in the case where the energy beam is modulated by the power lower in power level than the record-ready power level after the last pulse of the energy beam pulse train including at least one pulse for forming a mark portion and the mark portion is followed by a space portion of a predetermined length, the particular radiation energy of low power level is reduced as compared with when the mark portion is followed by a space potion of a different length.

Abstract: To provide an information recording medium which permits high density recording/reproduction, which has good thermal stability, and which, due to the use of an interface layer with a high sputter rate, has good recording/reproduction characteristics and is excellent for mass production. An information recording medium wherein the thickness of an interface layer 3 is 0.25 or more but 0.67 or less of the total thickness of a first protective layer 2 and the interface layer 3, and the interface layer 3 contains at least tantalum (Ta) and oxygen (O). The medium is excellent for mass production and has good recording/reproduction characteristics for high density recording/reproduction.

Abstract: A recording medium having a dummy signal area on at least one side of a recording area is used and information is recorded with a dummy signal added to at least one of the leading and trailing sides in the recorded information signal. The user data area remains unaffected by repeated overwriting so that recorded user data is reproduced correctly. In particular, the wave form distortion caused by fluidization of a recording film remains at the dummy signal area and does not affect the user data area, so that the reproduction of the target information (user data) is assured.

Abstract: An information recording medium and an optical recording system allow target information (such as an ad) to be displayed without requiring changes in hardware or physical specifications. The recording medium comprises a recording-limited area in which recording is made possible by canceling the limit after an instruction is issued for displaying the target information.

Abstract: An information recording medium having a substrate, a recording layer on which information is recorded in accordance with a change of atomic arrangement caused by irradiation of light, a first reflective layer, and a second reflective layer. The second reflective layer is formed on the first reflective layer. The first reflective layer includes an Al alloy as a main component and the second reflective layer includes an Ag alloy as a main component.