Patents by Inventor Nobuyuki Komura
Nobuyuki Komura 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: 7061703Abstract: A master information carrier capable of manufacturing a magnetic recording medium in which a preformat recording of information signals causing no reproduction signal detection errors arising from a pulse shift of a reproduction waveform is performed. A master information carrier 1 has an array of ferromagnetic thin films 3 arranged according to the pattern of information signals and is used for forming magnetization 4 of a pattern corresponding to the array pattern of the ferromagnetic thin film 3 in a magnetic recording medium by applying a magnetic field while opposing the master information carrier 1 against a magnetic recording medium 2. Each of the ferromagnetic thin films 3 is formed such that each pattern length A becomes equal to a length including a correction amount ? in addition to a length a between magnetic transition areas 6 of the magnetization 4 to be formed in the magnetic recording medium 2.Type: GrantFiled: October 14, 2003Date of Patent: June 13, 2006Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Tatsuaki Ishida, Keizo Miyata, Nobuyuki Komura, Yasuaki Ban, Taizou Hamada, Hideyuki Hashi
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Patent number: 7057834Abstract: A master information carrier capable of manufacturing a magnetic recording medium in which a preformat recording of information signals causing no reproduction signal detection errors arising from a pulse shift of a reproduction waveform is performed. A master information carrier 1 has an array of ferromagnetic thin films 3 arranged according to the pattern of information signals and is used for forming magnetization 4 of a pattern corresponding to the array pattern of the ferromagnetic thin film 3 in a magnetic recording medium by applying a magnetic field while opposing the master information carrier 1 against a magnetic recording medium 2. Each of the ferromagnetic thin films 3 is formed such that each pattern length A becomes equal to a length including a correction amount ? in addition to a length a between magnetic transition areas 6 of the magnetization 4 to be formed in the magnetic recording medium 2.Type: GrantFiled: March 29, 2001Date of Patent: June 6, 2006Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Tatsuaki Ishida, Keizo Miyata, Nobuyuki Komura, Yasuaki Ban, Taizou Hamada, Hideyuki Hashi
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Patent number: 6858329Abstract: A master disc capable of conducting a preformat recording by a magnetic transcription without causing any unevenness over an entire magnetic disc is provided. The master disc is provided with a radial land portion where an array of ferromagnetic thin films is formed and a concave portion against the land portion. The land portion and the concave portion are formed such that the land portion is joined with the surface of the magnetic disc when the present magnetic disc is overlapped on the magnetic disc, and that the concave portion is not contacted with the surface of the magnetic disc, and also that a space surrounded by the surface of the magnetic disc and the concave portion is open to air at a peripheral end portion of the magnetic disc.Type: GrantFiled: March 29, 2001Date of Patent: February 22, 2005Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Taizou Hamada, Hideyuki Hashi, Tatsuaki Ishida, Nobuyuki Komura, Yasuaki Ban, Keizo Miyata, Kiyokazu Tohma
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Publication number: 20040257687Abstract: A master information carrier capable of manufacturing a magnetic recording medium in which a preformat recording of information signals causing no reproduction signal detection errors arising from a pulse shift of a reproduction waveform is performed. A master information carrier 1 has an array of ferromagnetic thin films 3 arranged according to the pattern of information signals and is used for forming magnetization 4 of a pattern corresponding to the array pattern of the ferromagnetic thin film 3 in a magnetic recording medium by applying a magnetic field while opposing the master information carrier 1 against a magnetic recording medium 2. Each of the ferromagnetic thin films 3 is formed such that each pattern length A becomes equal to a length including a correction amount a in addition to a length a between magnetic transition areas 6 of the magnetization 4 to be formed in the magnetic recording medium 2.Type: ApplicationFiled: October 14, 2003Publication date: December 23, 2004Applicant: Matsushita Electric Industrial Co., Ltd.Inventors: Tatsuaki Ishida, Keizo Miyata, Nobuyuki Komura, Yasuaki Ban, Taizou Hamada, Hideyuki Hashi
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Photomask, method of generating resist pattern, and method of fabricating master information carrier
Patent number: 6821869Abstract: A recess for deaeration is formed in the surface of a resist film by using the photolithography technique, a photomask is allowed to come into contact with projections for close contact on both sides or around the recess for deaeration, and evacuation is performed via the recess for deaeration, thereby enhancing close contact between the photomask and the projections for close contact. With the configuration, a resist pattern having an accurate recess while preventing diffraction of light is formed.Type: GrantFiled: May 7, 2002Date of Patent: November 23, 2004Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Terumi Yanagi, Nobuyuki Komura, Tatsuaki Ishida, Keizo Miyata -
Patent number: 6714367Abstract: A master information carrier has a shape pattern corresponding to an information signal array to be recorded on a magnetic recording medium, and the shape pattern is provided by arraying a ferromagnetic thin film deposited on a nonmagnetic substrate surface. The ferromagnetic thin film is either a soft magnetic film or semihard magnetic film having not more than 40 kA/m coercive force in track length direction of the information signals, and residual magnetization of the ferromagnetic thin film in the track length direction of the information signals is greater than coercive force of the magnetic recording medium. As a result, a master information carrier with superior magnetic recording performance can be obtained.Type: GrantFiled: August 7, 2000Date of Patent: March 30, 2004Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Tatsuaki Ishida, Hiroshi Ryonai, Nobuyuki Komura, Keizo Miyata, Kiyokazu Tohma
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Photomask, method of generating resist pattern, and method of fabricating master information carrier
Publication number: 20020168839Abstract: A recess for deaeration is formed in the surface of a resist film by using the photolithography technique, a photomask is allowed to come into contact with projections for close contact on both sides or around the recess for deaeration, and evacuation is performed via the recess for deaeration, thereby enhancing close contact between the photomask and the projections for close contact. With the configuration, a resist pattern having an accurate recess while preventing diffraction of light is formed.Type: ApplicationFiled: May 7, 2002Publication date: November 14, 2002Applicant: Matsushita Electric Industrial Co., Ltd.Inventors: Terumi Yanagi, Nobuyuki Komura, Tatsuaki Ishida, Keizo Miyata -
Publication number: 20020159173Abstract: A master information carrier capable of manufacturing a magnetic recording medium in which a preformat recording of information signals causing no reproduction signal detection errors arising from a pulse shift of a reproduction waveform is performed. A master information carrier 1 has an array of ferromagnetic thin films 3 arranged according to the pattern of information signals and is used for forming magnetization 4 of a pattern corresponding to the array pattern of the ferromagnetic thin film 3 in a magnetic recording medium by applying a magnetic field while opposing the master information carrier 1 against a magnetic recording medium 2. Each of the ferromagnetic thin films 3 is formed such that each pattern length A becomes equal to a length including a correction amount &agr; in addition to a length a between magnetic transition areas 6 of the magnetization 4 to be formed in the magnetic recording medium 2.Type: ApplicationFiled: November 27, 2001Publication date: October 31, 2002Inventors: Tatsuaki Ishida, Keizo Miyata, Nobuyuki Komura, Yasuaki Ban, Taizuo Hamada, Hideyuki Hashi
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Publication number: 20020150794Abstract: A master disc capable of conducting a preformat recording by a magnetic transcription without causing any unevenness over an entire magnetic disc is provided. The master disc is provided with a radial land portion where an array of ferromagnetic thin films is formed and a concave portion against the land portion. The land portion and the concave portion are formed such that the land portion is joined with the surface of the magnetic disc when the present magnetic disc is overlapped on the magnetic disc, and that the concave portion is not contacted with the surface of the magnetic disc, and also that a space surrounded by the surface of the magnetic disc and the concave portion is open to air at a peripheral end portion of the magnetic disc.Type: ApplicationFiled: April 30, 2002Publication date: October 17, 2002Inventors: Taizou Hamada, Hideyuki Hashi, Tatsuaki Ishida, Nobuyuki Komura, Yasuaki Ban, Keizo Miyata, Kiyokazu Tohma
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Patent number: 5612146Abstract: A soft-magnetic multilayer thin film produced by electroplating, wherein an anode-dissolution process is effected by intermittently applying a reverse d.c. bias current with respect to the plating-forward current. Involving the anode-dissolution process allows the formation of a re-dissolution effect layer differing in crystal structure from the plated film layer. A soft-magnetic multilayer thin film characterized by having a multilayer film structure which comprises a plated layer and a re-dissolution effect layer laminated to each other and which the plated layer is at least magnetically isolated. Further, a method of manufacturing a soft-magnetic multilayer thin film having a multilayer film structure magnetically isolated only through plating, which is offered by introducing the anode-dissolution process.Type: GrantFiled: March 5, 1996Date of Patent: March 18, 1997Assignee: Matshushita Electric Industrial Co., Ltd.Inventors: Nobuyuki Komura, Yuuji Omata
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Patent number: 5575897Abstract: A soft-magnetic multilayer thin film produced by electroplating, wherein an anode-dissolution process is effected by intermittently applying a reverse d.c. bias current with respect to the plating-forward current. Involving the anode-dissolution process allows the formation of a re-dissolution effect layer differing in crystal structure from the plated film layer. A soft-magnetic multilayer thin film characterized by having a multilayer film structure which comprises a plated layer and a re-dissolution effect layer laminated to each other and which the plated layer is at least magnetically isolated. Further, a method of manufacturing a soft-magnetic multilayer thin film having a multilayer film structure magnetically isolated only through plating, which is offered by introducing the anode-dissolution process.Type: GrantFiled: October 24, 1995Date of Patent: November 19, 1996Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Nobuyuki Komura, Yuuji Omata