Patents by Inventor Tsutomu Aoyama

Tsutomu Aoyama 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).

  • Publication number: 20050220991
    Abstract: At least one ion 6 selected from Nb, Al, Cr and Mo is locally implanted into a thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt and a heat treatment is then carried out, and a portion 7 into which at least one ion 6 selected from Nb, Al, Cr and Mo is implanted becomes a portion 9 having a small coercive force and a portion 8 into which at least one ion 6 selected from Nb, Al, Cr and Mo is not locally implanted becomes a portion 10 having a large coercive force.
    Type: Application
    Filed: February 11, 2005
    Publication date: October 6, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Publication number: 20050214450
    Abstract: A thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt is heat treated and at least one ion 6 selected from B, Cr, Nb and Ga is locally implanted into a film 5 obtained after the heat treatment, and a portion 7 into which at least one ion 6 selected from B, Cr, Nb and Ga is locally implanted becomes a portion 9 having a small coercive force and a portion 8 into which at least one ion 6 selected from B, Cr, Nb and Ga is not locally implanted becomes a portion 10 having a large coercive force.
    Type: Application
    Filed: February 11, 2005
    Publication date: September 29, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Publication number: 20050196546
    Abstract: At least one ion 6 selected from Cr, Al, Nb and Mo is locally implanted into a thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt and a boron ion 20 is then implanted into a whole surface of the thin film subjected to the implantation, and a heat treatment is thereafter carried out, and a portion 7 into which at least one ion 6 selected from Cr, Al, Nb and Mo and the boron ion 20 are implanted becomes a portion 9 having a small coercive force and a portion 8 into which only the boron ion 20 is implanted becomes a portion 10 having a large coercive force.
    Type: Application
    Filed: February 8, 2005
    Publication date: September 8, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Publication number: 20050175790
    Abstract: A boron ion 6 is locally implanted into a thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt and a heat treatment is then carried out, and a portion 7 into which the boron ion 6 is implanted becomes a portion 9 having a large coercive force and a portion 8 into which the boron ion 6 is not locally implanted becomes a portion 10 having a small coercive force.
    Type: Application
    Filed: February 4, 2005
    Publication date: August 11, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Patent number: 6898840
    Abstract: A method of fabricating a magnetic head device comprising a slider having a magnetic head element, a suspension structure made of a thin resilient material and having one end supporting the slider and the other end to be attached to another member, and a head IC chip. The head IC chip is mounted on the suspension structure so as to face a magnetic recording disc and at a position spaced from the slider-supporting one end of the suspension structure by an intervening portion of the suspension structure. The position is selected so that the intervening portion is effective to suppress a temperature increase in the head IC chip due to at least thermal conduction through the intervening portion.
    Type: Grant
    Filed: February 17, 2000
    Date of Patent: May 31, 2005
    Assignee: TDK Corporation
    Inventors: Masashi Shiraishi, Izumi Nomura, Tsutomu Aoyama, Isamu Sato, Masanori Sakai, Tsuyoshi Umehara, Kenichi Takano, Haruyuki Morita
  • Publication number: 20050036224
    Abstract: A disc-shaped magnetic recording medium has magnetic tracks that are arranged thereon substantially concentrically for writing and reading magnetic information. Assuming that a saturation magnetic field in a width direction extending in a radial direction from the center of the disc-shaped magnetic recording medium is HR, and a saturation magnetic field in a circumferential direction perpendicular to the radial direction is HC, HR/HC is set to a value within a range of 0.5 to 0.95 in each of the magnetic tracks, and magnetization information is recorded in the width direction of each magnetic track. In gap portions between the magnetic tracks located adjacent to each other in the radial direction, discrete portions for magnetically separating the adjacent magnetic tracks are formed, respectively. With this configuration, it is possible to realize recording and reproduction in the magnetic track width direction.
    Type: Application
    Filed: November 19, 2003
    Publication date: February 17, 2005
    Applicant: TDK CORPORATION
    Inventor: Tsutomu Aoyama
  • Publication number: 20030211382
    Abstract: The present invention is designed to provide a secondary battery accommodation case with improved exterior surface having no parting line in two or more exterior faces out of four exterior faces encircling the battery accommodation portion. It comprises a substantially rectangular bottom case 11 having a battery accommodation portion 18 for accommodating secondary batteries 13 and a top case 12 to be assembled with the bottom case 11 for closing the battery accommodation portion 18. In the assembled condition of the top case 12 and the bottom case 11, the exterior face of the top case 12 closing the secondary battery accommodation portion 18 is made equal to or lower than two or more open edges 15a˜15d out of four exterior faces 11b˜11e encircling the battery accommodation portion 18 in the bottom case 11.
    Type: Application
    Filed: March 4, 2003
    Publication date: November 13, 2003
    Inventor: Tsutomu Aoyama
  • Patent number: 6620532
    Abstract: A patterned magnetic recording medium has clusters (2) in which minimum magnetic reversal units (21) with an intervening nonmagnetic region (3) are equidistantly arranged in longitudinal and transverse directions to form recording tracks, wherein the clusters (2) are arranged at equal intervals in the recording track longitudinal and transverse directions, the distance between two adjacent minimum magnetic reversal units in the longitudinal direction is UL within the cluster and CL between adjacent clusters, satisfying CL>UL, and the distance between two adjacent minimum magnetic reversal units in the transverse direction is UW within the cluster and CW between adjacent clusters, satisfying CW>UW.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: September 16, 2003
    Assignee: TDK Corporation
    Inventor: Tsutomu Aoyama
  • Patent number: 6541182
    Abstract: A method for forming a pattern in a resist is provided. A resist is formed on a surface of a substrate. A first portion of the resist is exposed to a charged particle beam, such as an electron beam, to alter a first characteristic of the first portion of the resist. A second portion of the resist is exposed to electromagnetic radiation, such as UV light, to alter a second characteristic of the second portion of the resist. The second portion is larger than the first portion. At least part of the first portion is removed using the altered characteristics of the resist such that a remaining portion defines the pattern in the resist. Using this method, fine pattern resists having less than 100 nm resolution may be created at high throughput rates.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: April 1, 2003
    Assignee: TDK Corporation
    Inventors: Isabelle Louis Joseph Dogue, Hitoshi Hatate, Tsuneo Kagotani, Tsutomu Aoyama
  • Patent number: 6522502
    Abstract: There is disclosed a magnetic disc device wherein temperature increase in the head IC chip can effectively suppressed. The magnetic head device comprises a slider having a magnetic head, a suspension structure having one end supporting the slider, and a head IC chip, the head IC chip being mounted on the suspension structure at a side adapted to be faced to a magnetic recording disc. A flow of air produced by the rotation of the magnetic disc cols the head IC chip in operation.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: February 18, 2003
    Assignee: TDK Corporation
    Inventors: Masashi Shiraishi, Izumi Nomura, Tsutomu Aoyama, Isamu Sato, Masanori Sakai, Tsuyoshi Umehara, Kenichi Takano, Haruyuki Morita
  • Patent number: 6495240
    Abstract: In conjunction with a so-called patterned medium comprising recording tracks each having an array of unit minute recording portions of a magnetic material separated by non-recording portions of a nonmagnetic material, the invention aims to prevent the recorded information from being disrupted by contact of a magnetic head slider with the medium. The magnetic recording medium of the invention includes recording tracks each having an array of unit minute recording portions (14) of a magnetic material separated by non-recording portions (16) of a nonmagnetic material. The surface height of the unit minute recording portions (14) is set lower than the surface height of the non-recording portions (16).
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: December 17, 2002
    Assignee: TDK Corporation
    Inventors: Yoshimitsu Wada, Tsutomu Aoyama
  • Patent number: 6420058
    Abstract: The invention aims to prevent inadvertent rewriting or erasure of servo information in a patterned medium based on the perpendicular recording mode. The magnetic recording medium of the invention includes recording tracks each having an array of unit minute recording portions of a magnetic material separated by non-recording portions of a nonmagnetic material. The recording tracks include data regions and servo regions. The unit minute recording portions in the data regions have substantially the same surface area as the unit minute recording portions in the servo regions. The invention satisfies ARS/ARD≧1.5 provided that the unit minute recording portion has an aspect ratio which is the thickness divided by the square root of the surface area, the unit minute recording portion in the data region has an aspect ratio ARD, and the unit minute recording portion in the servo region has an aspect ratio ARS.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: July 16, 2002
    Assignee: TDK Corporation
    Inventors: Susumu Haratani, Tsutomu Aoyama
  • Patent number: 6313969
    Abstract: A magnetic disk medium of the invention comprises a disk form of substrate, a multiplicity of unit minuscule recording areas formed of a magnetic material on the substrate to magnetically record information thereon and located concentrically or spirally at an interval in a peripheral or radial direction, and a non-recording area provided on the substrate and formed of a non-magnetic material that is embedded between the unit minuscule recording areas. Each unit minuscule recording area is in a form having a major axis and a minor axis, wherein the direction of the major axis is aligned with the radial direction of the substrate.
    Type: Grant
    Filed: April 5, 1999
    Date of Patent: November 6, 2001
    Assignee: TDK Corporation
    Inventors: Kazuhiro Hattori, Tsutomu Aoyama, Isamu Sato
  • Publication number: 20010016271
    Abstract: A patterned magnetic recording medium has clusters (2) in which minimum magnetic reversal units (21) with an intervening nonmagnetic region (3) are equidistantly arranged in longitudinal and transverse directions to form recording tracks, wherein the clusters (2) are arranged at equal intervals in the recording track longitudinal and transverse directions, the distance between two adjacent minimum magnetic reversal units in the longitudinal direction is UL within the cluster and CL between adjacent clusters, satisfying CL>UL, and the distance between two adjacent minimum magnetic reversal units in the transverse direction is UW within the cluster and CW between adjacent clusters, satisfying CW>UW.
    Type: Application
    Filed: January 18, 2001
    Publication date: August 23, 2001
    Applicant: TDK CORPORATION
    Inventor: Tsutomu Aoyama
  • Patent number: 6144524
    Abstract: A spin valve magnetoresistance device including a free magnetic layer, a pinned magnetic layer, a non-magnetic layer disposed between them and a permanent magnet film defining a track width x(in .mu.m) and configured to control magnetic domains of the free magnetic layer. The product of the residual magnetization (in .mu.emu/cm.sup.3) of the permanent magnet film times the thickness (in cm) thereof is given by f(x):f(x)=-11.24(1/x.sup.2)+A,where x.ltoreq.2 .mu.m, and 670 .mu.emu/cm.sup.2 .ltoreq.A.ltoreq.900 .mu.emu/cm.sup.2.
    Type: Grant
    Filed: April 7, 1999
    Date of Patent: November 7, 2000
    Assignee: TDK Corporation
    Inventors: Susumu Haratani, Tsutomu Aoyama, Isamu Sato
  • Patent number: 6084746
    Abstract: There is disclosed a magnetic disc device wherein temperature increase in the head IC chip can effectively suppressed. The magnetic head device comprises a slider having a magnetic head, a suspension structure having one end supporting the slider, and a head IC chip, the head IC chip being mounted on the suspension structure at a side adapted to be faced to a magnetic recording disc. A flow of air produced by the rotation of the magnetic disc cols the head IC chip in operation.
    Type: Grant
    Filed: March 3, 1998
    Date of Patent: July 4, 2000
    Assignee: TDK Corporation
    Inventors: Masashi Shiraishi, Izumi Nomura, Tsutomu Aoyama, Isamu Sato, Masanori Sakai, Tsuyoshi Umehara, Kenichi Takano, Haruyuki Morita
  • Patent number: 5698286
    Abstract: A magnetic layer is provided on a nonmagnetic base with a non-ferromagnetic layer interposed between them. Non-ferromagnetic particulate iron oxide is incorporated in the non-ferromagnetic layer. In addition to, or in place of, this iron oxide, non-structural carbon having a mean particle diameter of 10 to 60 nm, a specific surface area of 150 m2/g as measured by the BET method and a DBP oil absorption of 100 ml/100 g or less may be used. This makes it possible to achieve a magnetic recording medium having excellent surface properties and good-enough electromagnetic transducing characteristics.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: December 16, 1997
    Assignee: TDK Corporation
    Inventors: Tsunehiko Ikarashi, Yasufumi Takasugi, Tsutomu Aoyama, Akira Saitoh, Yuko Motegi, Takayoshi Kuwajima
  • Patent number: 5414554
    Abstract: An optical semiconductor amplifier of the present invention comprises an input optical waveguide medium for feeding input light. A first optical branching circuit which is included a first optical coupler splits the input light into two. An optical semiconductor amplifier amplifies one of two light split by the first optical branching circuit. A first photodetector receives the other of the two light and generates a corresponding first electric signal. A second optical branching circuit which is included a second optical coupler splits the light amplified from the optical semiconductor amplifier into two. A second photodetector receives one of two light split by the second optical branching circuit, and generates a corresponding second electric signal. An output optical waveguide receives the other of the two light split by the second optical branching circuit. A feedback control circuit controls an injection current to the optical semiconductor amplifier in response to the first and second electric signals.
    Type: Grant
    Filed: October 13, 1993
    Date of Patent: May 9, 1995
    Assignee: NEC Corporation
    Inventor: Tsutomu Aoyama
  • Patent number: 4794042
    Abstract: A magnetic recording medium wherein a magnetic layer containing a particulate magnetic material and a binder is formed on a substrate exhibits improved performance as magnetic recording tape, disk, and sheet when the particulate magnetic material comprises particles having iron carbide at least on the surface thereof and optional oxide particles, and the particulate magnetic material contains 5 to 90% by weight of iron carbide in the form of Fe.sub.n C.
    Type: Grant
    Filed: October 9, 1986
    Date of Patent: December 27, 1988
    Assignee: TDK Corporation
    Inventors: Yuichi Kubota, Keiji Koga, Kazunori Tamazaki, Tsutomu Aoyama, Akio Watanabe
  • Patent number: 4741977
    Abstract: A magnetic sheet comprising a disk-shaped substrate and a magnetic layer is loaded in a magnetic sheet operating device, typically electronic camera comprising a magnetic head for performing recording and reproducing operations on the sheet while rotating the sheet. The magnetic layer is formed from a composition comprising a magnetic powder and a binder having a specified complex elastic modulus.
    Type: Grant
    Filed: August 14, 1986
    Date of Patent: May 3, 1988
    Assignee: TDK Corporation
    Inventors: Keiji Koga, Keiko Tsuchiya, Kazunori Tamazaki, Tsutomu Aoyama, Yuichi Kubota