Patents by Inventor Masaki Itoh

Masaki Itoh 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).

  • Patent number: 5473583
    Abstract: A magnetooptical recording medium having a higher recording density, improved bit error rate and superior weather resistance and a recording and playback method for the same are provided. The magnetooptical recording medium has a first magnetooptical layer having a high Curie temperature a second perpendicularly magnetizable magnetooptical layer having a low Curie temperature and a third perpendicularly magnetizable magnetooptical layer having an intermediate Curie temperature set between the Curie temperatures of the first and second magnetooptical layers, laminated in this order on a substrate. The first, second and third magnetooptical layers are formed respectively of amorphous alloys containing GdFeCo, TbFeTi and TbFeCoTi as the main component thereof. The first, second and third magnetooptical layers are exchange-coupled at 10.degree. C. to 90.degree. C.
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: December 5, 1995
    Assignee: NEC Corporation
    Inventors: Masaki Itoh, Eizoh Fukami
  • Patent number: 5398219
    Abstract: A magnetooptical recording medium having a higher recording density, improved bit error rate and superior weather resistance and a recording and playback method for the same are provided. The magnetooptical recording medium has a first magnetooptical layer having a high Curie temperature, a second perpendicularly magnetizable magnetooptical layer having a low Curie temperature and a third perpendicularly magnetizable magnetooptical layer having an intermediate Curie temperature set between the Curie temperatures of the first and second magnetooptical layers, laminated in this order on a substrate. The first, second and third magnetooptical layers are formed respectively of amorphous alloys containing GdFeCo, TbFeTi and TbFeCoTi as the main component thereof. The first, second and third magnetooptical layers are exchange-coupled at 10.degree. C. to 90.degree. C.
    Type: Grant
    Filed: December 13, 1993
    Date of Patent: March 14, 1995
    Assignee: NEC Corporation
    Inventors: Masaki Itoh, Eizoh Fukami
  • Patent number: 5362537
    Abstract: For use in recording information by an irradiation of a laser beam, an optical information recording medium comprises a substrate transparent for the laser beam and a first and a second magneto-optical layer which are made of GdFeTi and TbFeCo, respectively. The first magneto-optical layer is between the substrate and the second magneto-optical layer and thermally coupled to the second magneto-optical layer. For carrying out a recording operation, the laser beam is irradiated to the substrate to heat the first magneto-optical layer. A temperature of the first magneto-optical layer is transferred to the second magneto-optical layer. In this condition, the second magneto-optical layer is subjected to a magnetic field representative of information. As a result, the information is recorded as recorded information to the second magneto-optical layer.
    Type: Grant
    Filed: March 30, 1993
    Date of Patent: November 8, 1994
    Assignee: NEC Corporation
    Inventor: Masaki Itoh
  • Patent number: 5292592
    Abstract: In an optical information recording medium comprising a substrate (11) of polycarbonate, a recording layer, and a reflecting layer (14) covering the reflecting layer and containing Al, an alloy layer (17) of a Ni-Cr alloy is deposited on the reflecting layer to sufficiently protect transmission of moisture into the reflecting layer. A covering layer (18) of ultraviolet curable resin may be deposited on the alloy layer. The recording layer is formed on the substrate and includes a magneto-optical layer (13) sandwiched between first and second interference layers (15, 16). For protecting transmission of moisture into the substrate, it is preferable that an additional layer (21) of SiO.sub.2 is deposited on the substrate opposite to the recording layer.
    Type: Grant
    Filed: May 8, 1992
    Date of Patent: March 8, 1994
    Assignee: NEC Corporation
    Inventor: Masaki Itoh
  • Patent number: 4839208
    Abstract: An optical information recording medium according to the present invention is featured by its recording layer which contains a compound of tellurium (Te), selenium (Se) and nitrogen (N). The thickness of the recording layer 2 favorably ranges from about 100 angstroms (.ANG.) to about 1000 .ANG. and more favorably from 180 .ANG. to 400 .ANG.. The content of Se in the recording layer 2 favorably lies within a range from 2 to 40 atomic percent, more favorably from 10 to 30 atomic percent. The content of N is favorably to be from 2 to 20 atomic percent, and more favorably from 2 to 10 atomic percent.
    Type: Grant
    Filed: April 28, 1987
    Date of Patent: June 13, 1989
    Assignee: NEC Corporation
    Inventors: Katsuji Nakagawa, Masaki Itoh, Akio Morimoto, Mitsuru Sakai
  • Patent number: 4775568
    Abstract: An optical information storage medium comprising a transparent substrate and an information carrying layer positioned on one side of the substrate, wherein the information carrying layer contains at least 30 per cent by volume of tin and at least 15 per cent by volume of cobalt oxide. The information carrying layer may be formed directly on one surface of the substrate.
    Type: Grant
    Filed: November 26, 1986
    Date of Patent: October 4, 1988
    Assignee: NEC Corporation
    Inventors: Masaki Itoh, Akio Morimoto
  • Patent number: 4763139
    Abstract: An optical information storage medium comprising a transparent substrate and an information carrying layer positioned on one side of the substrate, wherein the information carrying layer contains at least 30 percent by volume of tin and at least 20 percent by volume of nickel oxide. The information carrying layer may be formed directly on one surface of the substrate. Alternatively, the information storage medium may further comprise a first spacer layer formed on one surface of the substrate and a second spacer layer which intervenes between the first spacer layer and the information carrying layer, wherein the first spacer layer is substantially transparent to a radiation with a predetermined wavelength and is larger in refractive index than the substrate at the aforesaid wavelength and the second spacer layer is substantially transparent to the aforesaid radiation and is smaller in refractive index than the first spacer layer at the aforesaid wavelength.
    Type: Grant
    Filed: August 1, 1986
    Date of Patent: August 9, 1988
    Assignee: NEC Corporation
    Inventors: Masaki Itoh, Akio Morimoto, Sotaro Esho
  • Patent number: 4740447
    Abstract: An optical recording medium such as an optical disc memory, with which data can be stored and reproduced by means of laser beam with a high sensibility is disclosed.The optical recording medium comprises:a substrate transparent to the laser beam;a first spacer layer formed on the substrate, being substantially transparent to the laser beam and having a higher refractive index than the substrate with respect to said laser beam;a second spacer layer formed on the first spacer layer, being substantially transparent to the laser beam and having a lower refractive index than the first layer with respect to said laser beam; anda recording layer formed on the second spacer layer and for storing data therein by the radiation of laser beam.
    Type: Grant
    Filed: December 2, 1985
    Date of Patent: April 26, 1988
    Assignee: NEC Corporation
    Inventor: Masaki Itoh
  • Patent number: 4726060
    Abstract: A line circuit for driving a ringer and a service indicating lamp in a telephone set, including a high frequency transformer (T.sub.2), a switching circuit (22) for intermittently disconnecting a D.C. voltage applied to the primary winding of the transformer (T.sub.2), and a control signal generating circuit (23). The control signal generating circuit generates a first control signal having high frequency and having a first duty ratio when the ringer is to be rung; and generates a second control signal having the same frequency but having a second duty ratio smaller than the first duty ratio when the service indicating lamp is to be lit. The first or the second control signal is applied to the switching circuit so that the high frequency transformer generates a ringing signal or a D.C. voltage to light the lamp. Since the high-frequency transformer is commonly used for generating the ringing signal and the D.C. voltage for the lamp, the line circuit can be made small and light.
    Type: Grant
    Filed: December 27, 1985
    Date of Patent: February 16, 1988
    Assignee: Fujitsu Limited
    Inventors: Masaki Itoh, Junichi Koike, Yoshishige Tanaka
  • Patent number: 4504548
    Abstract: An optical recording medium is disclosed which allows information to be recorded thereinto and read thereoutof by means of semiconductor laser light. The recording medium comprises at least a substrate and a recording layer formed on one or both sides of the substrate. Information is recorded into and read from the recording layer by laser light. The recording layer comprises an organic film of a naphthoquinonoid dye corresponding to the following molecular formula or an organic film whose major component is the naphthoquinonoid dye: ##STR1## where R is a first auxochrome and R' a second auxochrome. The first auxochrome is a hydroxyl group, an amino group, or an alkyl substituted amino group, while the second auxochrome is a hydroxyl group, an amino group, an alkyl substituted amino group or ##STR2## where X' is a hydrogen atom, an alkyl group, an amino group, a substituted amino group or an alkoxyl group.
    Type: Grant
    Filed: June 23, 1983
    Date of Patent: March 12, 1985
    Assignee: NEC Corporation
    Inventors: Sotaro Esho, Masaki Itoh, Masaru Matsuoka
  • Patent number: 4501384
    Abstract: A device for mounting a container box on the upper rear side of a large-size motorcycle. The container box is slidably mounted so that position of the container box can be adjusted in the back and forth direction by the fellow passenger without using any special tool. The fellow passenger is relieved from fatigue in long-distance touring because he can change the position of his body by the adjustment of the position of the container box which serve as a back rest.
    Type: Grant
    Filed: March 25, 1983
    Date of Patent: February 26, 1985
    Assignee: Kawasaki Jukogyo Kabushiki Kaisha
    Inventor: Masaki Itoh
  • Patent number: 4279986
    Abstract: A lithographic resist for use in microfabrication comprising a negative-type resist containing a radical scavenger capable of preventing post-irradiation reaction.
    Type: Grant
    Filed: July 23, 1979
    Date of Patent: July 21, 1981
    Assignee: Nippon Electric Co., Ltd.
    Inventors: Yoshitake Ohnishi, Masaki Itoh, Kenji Mizuno, Hiroshi Gokan
  • Patent number: 4084656
    Abstract: The device prevents starting of the engine of a two-wheeled motorcycle even if the two-wheeled motorcycle is brought to an upright position and an attempt is made to start the engine, unless the stand is in an inoperative position. A stand switch is opened by the stand when the latter is in a neutral position so that the ignition circuit for the engine cannot be rendered operative, thereby to prevent actuation of the engine. When the stand is in either the inoperative position or the operative position, the stand switch is closed to permit the engine to be started. A normally open manually-operated switch shunts the stand switch and is capable of operating the ignition circuit regardless of whether the stand switch is closed or open.
    Type: Grant
    Filed: April 21, 1977
    Date of Patent: April 18, 1978
    Assignee: Kawasaki Jukogyo Kabushiki Kaisha
    Inventors: Masaki Itoh, Yorio Yamasaki