Patents by Inventor Keikichi Andoo
Keikichi Andoo has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 6775226Abstract: An information recording medium, which comprises three thin films of different compositions, comprising first and second interference layers and a first interface layer, stacked in this order from the laser beam incident side of a recording layer, the refractive index of the second interference layer being lower than that of any one of the first interference layer and the recording layer, the first interface layer being provided in contact with the recording layer and between the second interference layer and the recording layer, the second interference layer containing oxygen, and an oxygen barrier layer having a smaller oxygen content than that of the second interference layer being provided in contact with the second interference layer and between the second and first interface layers, can control diffusion of oxygen from the second interference layer into the recording layer and prevents deterioration of overwriting at the time of many runs of overwriting and lowering of storage life.Type: GrantFiled: August 30, 2001Date of Patent: August 10, 2004Assignee: Hitachi, Ltd.Inventors: Makoto Miyamoto, Junko Ushiyama, Keikichi Andoo
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Patent number: 6740382Abstract: 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.Type: GrantFiled: July 23, 2002Date of Patent: May 25, 2004Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.Inventors: Makoto Miyamoto, Akemi Hirotsune, Keikichi Andoo, Tetsuya Nishida, Motoyasu Terao, Junko Ushiyama, Yumiko Anzai
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Publication number: 20040081052Abstract: 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.Type: ApplicationFiled: June 23, 2003Publication date: April 29, 2004Applicant: Hitachi, Ltd.Inventors: Makoto Miyamoto, Tsuyoshi Toda, Masatoshi Ohtake, Motoyasu Terao, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai, Akemi Hirotsune, Tetsuya Nishida, Hideki Saga
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Patent number: 6723411Abstract: 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.Type: GrantFiled: February 26, 2002Date of Patent: April 20, 2004Assignee: Hitachi, Ltd.Inventors: Akemi Hirotsune, Makoto Miyamoto, Toshimichi Shintani, Keikichi Andoo, Yumiko Anzai, Takahiro Kurokawa
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Patent number: 6709801Abstract: A high-density information recording medium free from lowering the reflectance by over-write of a large number of times and exfoliation defect in a structure for suppressing cross-erase. This medium includes, over a substrate having a groove shape, a recording layer, and three-layered thin films of a first interference layer, a second interference layer and an interface layer having mutually different compositions and disposed on a laser beam incidence side of the recording layer in order named from the laser beam incidence side. The first interference layer has a smaller refractive index and a larger thermal conductivity than the second interference layer, the interface layer is interposed between the second interference layer and the recording layer, and a distance between the first interference layer and the recording layer is greater than at least a groove depth.Type: GrantFiled: January 24, 2001Date of Patent: March 23, 2004Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.Inventors: Makoto Miyamoto, Yoshihiro Ikari, Tamotsu Fuchioka, Hitoshi Watanabe, Reiji Tamura, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai
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Patent number: 6703098Abstract: 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.Type: GrantFiled: February 19, 2002Date of Patent: March 9, 2004Assignee: Hitachi, Ltd.Inventors: Akemi Hirotsune, Motoyasu Terao, Junko Ushiyama, Hiroyuki Minemura, Keikichi Andoo, Yumiko Anzai, Makoto Miyamoto
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Publication number: 20030174610Abstract: 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.Type: ApplicationFiled: August 16, 2002Publication date: September 18, 2003Applicant: Hitachi, Ltd.Inventors: Makoto Miyamoto, Akemi Hirotsune, Toshimichi Shintani, Takahiro Kurokawa, Keikichi Andoo, Yumiko Anzai
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Patent number: 6608806Abstract: 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.Type: GrantFiled: October 16, 2002Date of Patent: August 19, 2003Assignee: Hitachi, Ltd.Inventors: Makoto Miyamoto, Tsuyoshi Toda, Masatoshi Ohtake, Motoyasu Terao, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai, Akemi Hirotsune, Tetsuya Nishida, Hideki Saga
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Publication number: 20030124387Abstract: 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.Type: ApplicationFiled: February 26, 2002Publication date: July 3, 2003Inventors: Akemi Hirotsune, Makoto Miyamoto, Toshimichi Shintani, Keikichi Andoo, Yumiko Anzai, Takahiro Kurokawa
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Publication number: 20030068461Abstract: 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.Type: ApplicationFiled: July 23, 2002Publication date: April 10, 2003Inventors: Makoto Miyamoto, Akemi Hirotsune, Keikichi Andoo, Tetsuya Nishida, Motoyasu Terao, Junko Ushiyama, Yumiko Anzai
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Publication number: 20030064211Abstract: 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.Type: ApplicationFiled: February 19, 2002Publication date: April 3, 2003Applicant: Hitachi, Ltd.Inventors: Akemi Hirotsune, Motoyasu Terao, Junko Ushiyama, Hiroyuki Minemura, Keikichi Andoo, Yumiko Anzai, Makoto Miyamoto
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Patent number: 6529467Abstract: 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.Type: GrantFiled: December 21, 2001Date of Patent: March 4, 2003Assignee: Hitachi, Ltd.Inventors: Makoto Miyamoto, Tsuyoshi Toda, Masatoshi Ohtake, Motoyasu Terao, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai, Akemi Hirotsune, Tetsuya Nishida, Hideki Saga
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Publication number: 20030039192Abstract: 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.Type: ApplicationFiled: October 16, 2002Publication date: February 27, 2003Inventors: Makoto Miyamoto, Tsuyoshi Toda, Masatoshi Ohtake, Motoyasu Terao, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai, Akemi Hirotsune, Tetsuya Nishida, Hideki Saga
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Publication number: 20030039200Abstract: In a multilayered optical disk having n layers of recording layers, it is designed in such a manner that transmittance Ti of the ith layer from a light-incident side fulfills 1 ∏ i = 1 j - 1 ⁢ T i 2 ≥ n - j + 1 nType: ApplicationFiled: February 12, 2002Publication date: February 27, 2003Inventors: Toshimichi Shintani, Motoyasu Terao, Keikichi Andoo
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Patent number: 6436504Abstract: An information recording medium having a substrate, a lower superficial layer formed on the substrate and having a thickness of not more than 25 nm, and a recording layer formed on the lower superficial layer. Information is recorded on the recording layer in accordance with a change of atomic arrangement caused by irradiation of light. The information recording medium includes and an absorption control layer formed on the recording layer.Type: GrantFiled: April 11, 2001Date of Patent: August 20, 2002Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.Inventors: Makoto Miyamoto, Akemi Hirotsune, Keikichi Andoo, Tetsuya Nishida, Motoyasu Terao, Junko Ushiyama, Yumiko Anzai
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Publication number: 20020054556Abstract: 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.Type: ApplicationFiled: December 21, 2001Publication date: May 9, 2002Applicant: Hitachi, Ltd.Inventors: Makoto Miyamoto, Tsuyoshi Toda, Masatoshi Ohtake, Motoyasu Terao, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai, Akemi Hirotsune, Tetsuya Nishida, Hideki Saga
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Publication number: 20020015914Abstract: An information recording medium which includes at least a recording layer, and first and second metallic layers disposed on an opposite side of an energy beam incident side of the recording layer and having different compositions, and in which the first one of the first and second metallic layers located closer to the recording layer contains Al, Ag, Au, Pt and Pd as its main components and a sum of contents of these atoms is 60% or more. Thereby recording and reproducing of information can be realized with a high reliability.Type: ApplicationFiled: September 24, 2001Publication date: February 7, 2002Inventors: Makoto Miyamoto, Motoyasu Terao, Yukio Fukui, Nobuhiro Tokushuku, Keikichi Andoo, Tetsuya Nishida, Akemi Hirotsune, Yasushi Miyauchi, Koichi Moritani
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Patent number: 6343056Abstract: 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.Type: GrantFiled: February 2, 2001Date of Patent: January 29, 2002Assignee: Hitachi, Ltd.Inventors: Makoto Miyamoto, Tsuyoshi Toda, Masatoshi Ohtake, Motoyasu Terao, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai, Akemi Hirotsune, Tetsuya Nishida, Hideki Saga
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Patent number: 6340555Abstract: An information recording medium which includes at least a recording layer, and first and second metallic layers disposed on an opposite side of an energy beam incident side of the recording layer and having different compositions, and in which the first one of the first and second metallic layers located closer to the recording layer contains Al, Ag, Au, Pt and Pd as its main components and a sum of contents of these atoms is 60% or more. Thereby recording and reproducing of information can be realized with a high reliability.Type: GrantFiled: August 15, 2000Date of Patent: January 22, 2002Assignee: Hitachi, Ltd.Inventors: Makoto Miyamoto, Motoyasu Terao, Yukio Fukui, Nobuhiro Tokushuku, Keikichi Andoo, Tetsuya Nishida, Akemi Hirotsune, Yasushi Miyauchi, Koichi Moritani
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Publication number: 20010043538Abstract: 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.Type: ApplicationFiled: February 2, 2001Publication date: November 22, 2001Applicant: Hitachi, Ltd.Inventors: Makoto Miyamoto, Tsuyoshi Toda, Masatoshi Ohtake, Motoyasu Terao, Junko Ushiyama, Keikichi Andoo, Yumiko Anzai, Akemi Hirotsune, Tetsuya Nishida, Hideki Saga