Patents by Inventor Hideki Saga
Hideki Saga 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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Publication number: 20060236024Abstract: Embodiments of the invention provide an easy-to-operate information read/write device that operates with minimum electric power consumption, has an excellent prevention effect against EMI, is small in weight and in physical size, and is particularly suitable for use in hand-held devices. In one embodiment, an information read/write device having a processor A to control a scanning module for a recording medium, a write signal processing module, and a read signal processing module, and a processor B for instructing the processor A to write information onto or read information from the recording medium, is further provided with a memory module which is random-accessible from the processors A and B and into which the information to be written or read is stored.Type: ApplicationFiled: April 10, 2006Publication date: October 19, 2006Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Hideki Saga, Motoyasu Tsunoda, Terumi Takashi
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Patent number: 7054234Abstract: A recording head for decreasing recording noise accompanying malformation of a recorded mark and to form the recorded mark capable of increasing reproduction resolution at the time of magnetic reproduction. The head has a light source and a scatterer for recording information on a recording medium by generating near-field light by application of light from the light source and forming a magnetic domain array on the recording medium, a perimeter of the scatterer defines a plurality of vertices and a distance between a first vertex and a last vertex is shorter than the width of the recording track on the recording medium. The recording head improves recording density and can be used to manufacture a highly reliable information recording and reproducing apparatus having a reduced cost per capacity.Type: GrantFiled: January 30, 2003Date of Patent: May 30, 2006Assignee: Hitachi, Ltd.Inventors: Hideki Saga, Takuya Matsumoto
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Patent number: 7042823Abstract: Recording information is disclosed in which an information recording medium is irradiated with a recording energy beam that is power-modulated into at least a record power level and a record-ready power level lower than the record power level. The information is recorded on the recording medium in the form of length and interval of a mark portion. 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.Type: GrantFiled: June 30, 2005Date of Patent: May 9, 2006Assignee: 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: 7012871Abstract: 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: November 3, 2004Date of Patent: March 14, 2006Assignee: 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: 20050270682Abstract: Embodiments of the invention reduce the peak consumption current of a disk drive and that of its application system, and to minimize the limitation of the consumption current so that the performance deterioration of the disk drive and its application system is minimized. In one embodiment, a monitor terminal is provided to enter the pre-regulated output voltage of the voltage constant power supply. The disk drive is controlled so as to suppress the currents consumed by individual sections in the disk drive if the monitored voltage falls to a predetermined reference voltage.Type: ApplicationFiled: June 2, 2005Publication date: December 8, 2005Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventor: Hideki Saga
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Publication number: 20050259343Abstract: A thermally assisted magnetic recording system is provided to achieve excellent thermal resistance and low noise. In one embodiment, a magnetic recording medium is used, in which the magnetic intergrain exchange coupling is large to let the magnetization be thermally stable by coupling the magnetic grains constituting the recording layer at room temperature (the temperature maintaining the magnetization) and reduced by heating during recording to let the recording magnetization transition slope become steep. Parameter A normalizing the slope around the coercivity of the MH-loop of the medium is 1.5?A<6.0 at room temperature, and it becomes approximately 1.0 with heating.Type: ApplicationFiled: May 19, 2005Publication date: November 24, 2005Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Fumiko Akagi, Masukazu Igarashi, Hideki Saga
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Publication number: 20050259555Abstract: Recording information is disclosed in which an information recording medium is irradiated with a recording energy beam that is power-modulated into at least a record power level and a record-ready power level lower than the record power level. The information is recorded on the recording medium in the form of length and interval of a mark portion. 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.Type: ApplicationFiled: June 30, 2005Publication date: November 24, 2005Inventors: 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: 20050237890Abstract: Recording information is disclosed in which an information recording medium is irradiated with a recording energy beam that is power-modulated into at least a record power level and a record-ready power level lower than the record power level. The information is recorded on the recording medium in the form of length and interval of a mark portion. 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.Type: ApplicationFiled: June 30, 2005Publication date: October 27, 2005Inventors: 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: 20050088943Abstract: 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: November 3, 2004Publication date: April 28, 2005Inventors: 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: 6842415Abstract: 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: June 23, 2003Date of Patent: January 11, 2005Assignee: 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: 6809908Abstract: A light induction type thin film magnetic recording head according to the present invention includes a lower magnetic core (2) formed on a substrate, an upper magnetic core (6) whose front end part is connected to the lower magnetic core through a magnetic gap film and whose rear end part is directly connected to the lower magnetic core with a back contact part (11) formed of a magnetic substance, and an insulating layer (3) formed between the upper magnetic core and the lower magnetic core, characterized in that an optically transparent waveguide part (5) whose width is smaller than the width of the upper magnetic core and whose thickness is thinner than the thickness of the upper magnetic core is buried in the upper magnetic core, and a coil (8) which generates magnetic flux in a magnetic circuit composed of the upper magnetic core, lower magnetic core, magnetic gap, and back contact part is arranged around the back contact part.Type: GrantFiled: May 20, 2002Date of Patent: October 26, 2004Assignee: Hitachi, Ltd.Inventors: Kenchi Ito, Hideki Saga, Hiroaki Nemoto, Tomohiro Okada
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Patent number: 6778471Abstract: In an optical recording and magnetic-head reproducing system, the reproduced output is prevented from starting to decrease, upon the length of record bits getting shorter, in the range of the bit length larger than reproducing resolution of a magnetic reproducing head. When data are recorded magneto-optically on a magnetic recording medium, the radius of curvature of arcs constituting the boundary of recorded magnetic domains is made as large as possible so that the shape of the recorded spot may be substantially rectangular. As a result, it becomes possible to improve the efficiency of magnetic reproduction, and high-output as well as high-SN-ratio reproduction at high linear recording density can be achieved.Type: GrantFiled: June 27, 2000Date of Patent: August 17, 2004Assignee: Hitachi, Ltd.Inventors: Kazuetsu Yoshida, Hiroaki Nemoto, Hideki Saga
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Publication number: 20040085862Abstract: A near-field optical probe and optical near-field generator are provided. A problem of a probe having a scatterer in which optical near-field noises are generated at the parts other than for a point at which an intense optical near-field is generated, is solved. In one example of the probe, a surface of the parts except for a vertex of the scatterer at which the intense optical near-field is generated is etched so that an etching depth becomes not less than a penetration depth of the optical near-field. The probe facilitates control of noises when a sample is observed or recording marks are reproduced.Type: ApplicationFiled: June 6, 2003Publication date: May 6, 2004Applicant: Hitachi, Ltd.Inventors: Takuya Matsumoto, Hideki Saga
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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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Publication number: 20040081031Abstract: To generate a satisfactory recording magnetic domain on a recording medium and to improve the durability of a recording head, an information recording apparatus for generating an optical near field and thermo-magnetically recording information on the recording medium is provided with a light source, a magnetic pole for applying a magnetic field to the recording medium and a diffuser that generates an optical near field in the vicinity of the recording medium when light from the light source is radiated. The diffuser is formed with it in contact with the magnetic pole so that the face which light from the light source irradiates is substantially perpendicular to the recording medium. Thereby, recording density in the information recording apparatus can be increased, simultaneously the reliability can be also enhanced and as a result, the cost can be reduced.Type: ApplicationFiled: October 31, 2003Publication date: April 29, 2004Inventors: Hideki Saga, Takuya Matsumoto, Kei Ishikawa, Hirofumi Sukeda
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Publication number: 20040052178Abstract: An information recording apparatus includes an energy generation device for generating recording energy; a position control device for controlling a position of irradiation on the recording medium with an output of the energy generation device; a drive device for driving the energy generation device; a switching device for switching information based on user data and test information to supply the two kinds of information selectively to the drive device; a reading device for reading the marks recorded on the recording medium; an evaluation device for evaluating a reproduced signal obtained by the reading device; and a recording condition control device for controlling a recording condition on the basis of an evaluation result obtained by the evaluation device, wherein, when the marks used for recording the test information are to be reproduced, controlling operation of the position control device is changed to be different from that used for recording the test information.Type: ApplicationFiled: July 21, 2003Publication date: March 18, 2004Inventor: Hideki Saga
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Patent number: 6683823Abstract: A method for reproducing information on a recording medium includes irradiating electromagnetic energy or light to the recording medium from one side with respect to the recording medium, applying a recording magnetic field to an electromagnetic energy or light irradiated position on the recording medium from the one side of irradiating electromagnetic energy or light, and detecting magnetic leakage flux emerging from the recording medium from the one side of irradiating electromagnetic energy or light.Type: GrantFiled: December 17, 2002Date of Patent: January 27, 2004Assignee: Hitachi, Ltd.Inventors: Hideki Saga, Hiroaki Nemoto, Hirofumi Sukeda, Masahiko Takahashi, Kimio Nakamura, Yohji Maruyama, Hiroshi Ide, Takehiko Hamaguchi
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Patent number: 6678220Abstract: An information recording apparatus includes an energy generation device for generating recording energy; a position control device for controlling a position of irradiation on the recording medium with an output of the energy generation device; a drive device for driving the energy generation device; a switching device for switching information based on user data and test information to supply the two kinds of information selectively to the drive device; a reading device for reading the marks recorded on the recording medium; an evaluation device for evaluating a reproduced signal obtained by the reading device; and a recording condition control device for controlling a recording condition on the basis of an evaluation result obtained by the evaluation device, wherein, when the marks used for recording the test information are to be reproduced, controlling operation of the position control device is changed to be different from that used for recording the test information.Type: GrantFiled: May 31, 2000Date of Patent: January 13, 2004Assignee: Hitachi, Ltd.Inventor: Hideki Saga
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Publication number: 20030223316Abstract: A recording head for decreasing recording noise accompanying malformation of a recorded mark and to form the recorded mark capable of increasing reproduction resolution at the time of magnetic reproduction. The head has a light source and a scatterer for recording information on a recording medium by generating near field light by application of light from the light source and forming a magnetic domain array on the recording medium, a perimeter of the scatterer defines a plurality of vertices and a distance between a first vertex and a last vertex is shorter than the width of the recording track on the recording medium. The recording head improves recording density and can be used to manufacture a highly reliable information recording and reproducing apparatus having a reduced cost per capacity.Type: ApplicationFiled: January 30, 2003Publication date: December 4, 2003Applicant: Hitachi, Ltd.Inventors: Hideki Saga, Takuya Matsumoto
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Patent number: 6614737Abstract: An optical reproduction apparatus includes a light source which irradiates irradiation light onto a recording medium, the irradiation light being reflected by the recording medium to produce reflection light, a modulator which repetitively pulse modulates the irradiation light to produce irradiation light pulses, a photodetector which detects reflection light from the recording medium at more than two timings during each of the irradiation light pulses, and outputs detection signals respectively representative of the reflection light detected at the more than two timings during each of the irradiation light pulses, and an operation circuit which performs an operation between the detection signals outputted from the photodetector during each of the irradiation light pulses.Type: GrantFiled: February 15, 2002Date of Patent: September 2, 2003Assignee: Hitachi, Ltd.Inventors: Harukazu Miyamoto, Hideki Saga, Seiji Yonezawa