Patents by Inventor Yasuo Hira

Yasuo Hira 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: 5191624
    Abstract: An optical waveguide is comprised of an optical substrate and an optical thin-film optical waveguide layer and formed such that ##EQU1## where .theta. is an output angle, n.sub.o1 is an ordinary refractive index of the optical substrate for an ordinary beam, n.sub.e1 is an extraordinary refractive index of the optical substrate for an extraordinary beam, n.sub.o2 is an ordinary refractive index of the optical thin-film optical waveguide layer for the ordinary beam and n.sub.e2 is an extraordinary refractive index of the optical thin-film optical waveguide layer for the extraordinary beam, and an electrode for generating a surface acoustic wave for diffracting light is formed on the optical waveguide to construct a collinear optical deflector.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: March 2, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Kenchi Ito, Kazumi Kawamoto, Naoya Kanda, Yasuo Hira, Hidemi Sato, Atsuko Fukushima, Masataka Shiba, Akira Inagaki, Minoru Yoshida
  • Patent number: 5125740
    Abstract: A sample is located so as to be close to a prism and a light beam coming from a light source is projected to the prism while varying the incident angle to the prism as a parameter. The incident light beam to the prism is propagated therein and light emerging from the bottom surface of the prism, which is in contact with the sample, is projected to the sample. At the same time the intensity of light reflected by the bottom surface of the prism is measured. Optical constants such as the refractive index, the film thickness, the distribution of the refractive index, etc. are obtained by calculation, starting from measured values thus obtained.
    Type: Grant
    Filed: February 15, 1990
    Date of Patent: June 30, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Hidemi Sato, Yasuo Hira, Atsuko Fukushima, Hiroshi Asao, Kazumi Kawamoto, Kenchi Ito, Ryuichi Funatsu
  • Patent number: 5070488
    Abstract: An optical integrated circuit and an optical apparatus used in optical communication or an opto-electronics apparatus such as an optical disk recording apparatus, in which various kinds of aberration caused by wavelength variation of a light source when a semiconductor laser is used as the light source. An aberration correcting grating having such grating pitches as to nearly satisfy the Bragg condition preferably with respect to a certain wavelength of the semiconductor laser beam is used. As a result, lowering of incidence (entrance) and radiation (exit) coupling efficiencies of the grating coupler and aberration such as chromatic aberration can be prevented. Even if a multi-mode semiconductor laser is used as a light source, the characteristics of the optical integrated circuit and optical apparatus do not vary largely.
    Type: Grant
    Filed: June 28, 1989
    Date of Patent: December 3, 1991
    Inventors: Atsuko Fukushima, Yasuo Hira, Hidemi Sato, Kazumi Kawamoto, Kenchi Ito, Masataka Shiba, Akira Arimoto
  • Patent number: 4927044
    Abstract: Cases for automobile air conditioners or car-loaded refrigerators are molded in an integrated structure of a body part and fixing parts by reaction injection molding from a mixture of a liquid A comprising 20-60% by weight of an aliphatic amine-based polyol, 30-60% by weight of a PO adduct of 4,4'-diaminodiphenylmethane and 15-40% by weight of an ordinary polyol and further containing a foam-controlling agent, a foaming agent and a catalyst and a liquid B comprising polyisocyanate as obtained through impingement.
    Type: Grant
    Filed: February 28, 1985
    Date of Patent: May 22, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Masao Gotoh, Yasuo Hira, Kenichi Waragai, Shozo Nakamura, Hitoshi Yokono
  • Patent number: 4906063
    Abstract: This invention relates to a wave guide type optical device as an integrated optical device having formed thereon lens and grating having particularly high efficiency and a fabrication method thereof. The present invention is characterized in that a wave guide type optical device having high efficiency and high stability can be fabricated efficiently by forming a buffer layer made of a dielectric substance on a optical wave guide formed near the surface of a substrate having an acousto-optic effect, then forming a light wave control loading layer and finely working the loading layer and the buffer layer to a predetermined shape of a desired optical device.
    Type: Grant
    Filed: January 29, 1988
    Date of Patent: March 6, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Hidemi Sato, Yasuo Hira, Shigeru Sasaki, Atsuko Fukusima, Kazumi Kawamoto
  • Patent number: 4904037
    Abstract: A waveguide type optical device in which a waveguide layer for propagating light is provided on the front surface of a substrate, and a compensation layer having a coefficient of thermal expansion substantially equal to that of the waveguide layer formed on the front surface is provided on the rear surface of the substrate.
    Type: Grant
    Filed: July 28, 1988
    Date of Patent: February 27, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Katsuyuki Imoto, Hirohisa Sano, Yasuo Hira
  • Patent number: 4544462
    Abstract: The present invention provides a process for removing a metal surface oxide from a metallic substance by contacting the metal surface oxide layer with a deterging liquid to introduce electrons into the metal surface oxide in contact with the deterging liquid to dissolve the metal surface oxide, which process is characterized in that a metal piece or carbon piece is immersed in the deterging liquid into which gaseous hydrogen has been introduced and the metal piece or carbon piece is electrically connected to the metal surface oxide on the metallic substance. The metal piece is preferably platinum or vanadium. A preferred deterging liquid is one having a pH of about 5 to 7 and containing a complexing agent.
    Type: Grant
    Filed: June 13, 1984
    Date of Patent: October 1, 1985
    Assignees: Hitachi, Ltd., Hitachi Engineering Co., Ltd.
    Inventors: Yasumasa Furutani, Yasuo Hira, Takashi Hasegawa, Akira Minato, Saburo Shoji, Osao Sumita
  • Patent number: 4514270
    Abstract: A cleaning fluid such as a chemical decontamination solution originally containing one or more cleaning or decontamination reagents in low concentrations and deteriorated after a cleaning or decontamination treatment step by containing metal oxides therein can be regenerated by introducing such a deteriorated cleaning fluid into an electrolytic cell, passing a direct current through said cleaning fluid between two electrodes, and removing said metal oxides by depositing dissolved metal ions on the cathode as metals from the cleaning fluid.
    Type: Grant
    Filed: September 24, 1982
    Date of Patent: April 30, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yasumasa Furutani, Yasuo Hira, Takashi Hasegawa, Akira Minato, Osao Sumita, Hisao Itow
  • Patent number: 4478902
    Abstract: A screen for projection television set comprising a foamed support and a reflective film adhered to the concave side of the support, said support having the outer layers with a high density such as 0.7 to 1.2 g/cm.sup.3 and the inner portion with a low density so as to make the density of the foamed support as a whole 0.2 to 0.5 g/cm.sup.3, has good projection properties, surface hardness with sufficiently strong support. When said support is foam molded by using a polyurethane having special polyol components, its heat resistance is remarkably increased and can be foam molded at high temperatures without deformation.
    Type: Grant
    Filed: September 1, 1981
    Date of Patent: October 23, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Susumu Tsuzuku, Yasuo Hira, Masao Gotoh, Hitoshi Yokono, Yoshihisa Hosoe
  • Patent number: 4473662
    Abstract: In a composition for producing polyurethane foam which comprises an organic polyisocynate compound, a compound having at least one active hydrogen atom in the molecule, a foaming agent and a catalyst as essential components, an aminoalkylsilane represented by the following general formula is contained: ##STR1## wherein n is 1 or 2, and R.sub.1 to R.sub.5 are alkyl groups. By use of such a catalyst polyurethane foam having a even color distribution and excellent mechanical properties is produced.
    Type: Grant
    Filed: November 30, 1982
    Date of Patent: September 25, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Hira, Susumu Tsuzuku, Masao Gotoh, Hitoshi Yokono
  • Patent number: 4444704
    Abstract: Integral skin polymethane foams can be produced in a short time by impingement mixing a solution comprising polyols containing as an essential component a polyol derived from aromatic amine, a blowing agent and a special catalyst of tertiary amine salt having a hetero ring in the molecule, with a solution comprising one or more polyisocyanates, followed by injection into a closed mold and foaming and curing therein.
    Type: Grant
    Filed: January 19, 1982
    Date of Patent: April 24, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Hira, Susumu Tsuzuku, Masao Gotoh, Hitoshi Yokono, Reishi Naka
  • Patent number: 4409341
    Abstract: A composition for polyurethane foam comprising (a) polyols containing at least one of alkylene oxide adducts of aniline-formaldehyde condensates and alkylene oxide adducts of reduced compounds of nitrated toluenes in an amount of 30 to 70% by weight of the polyols, (b) at least one isocyanate of the formula: ##STR1## a fire retardant, together with one or more conventional catalysts, foam stabilizers, blowing agents and the like additives, can give fire retardant, high impact and heat resistant urethane foams.
    Type: Grant
    Filed: December 31, 1981
    Date of Patent: October 11, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Hira, Susumu Tsuzuku, Makoto Iida, Masao Gotoh, Hitoshi Yokono, Yoshikazu Kimura, Kazumi Iijima
  • Patent number: 4342842
    Abstract: Rigid polyurethane foams having excellent heat resistance and impact resistance can be produced with good workability due to good flow properties by using a composition comprising a polyol, a polyisocyanate, a blowing agent and a reaction accelerator as essential component, characterized by using as the polyol, a mixture of (a) an alkylene oxide adduct of 4,4'-diaminodiphenylmethane having OH value of 280-600 mg KOH/g, (b) an aliphatic polyether having a hdyroxyl value of 450-800 mg KOH/g and 3 or 4 hydroxyl groups in the molecule, and (c) a polyether having a hydroxyl value of 30 to 100 mg KOH/g and 2 or 3 hydroxyl groups in the molecule, in limited amounts.
    Type: Grant
    Filed: July 6, 1981
    Date of Patent: August 3, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Hira, Susumu Tsuzuku, Masao Gotoh, Hitoshi Yokono, Hiroshi Kaneko, Yoshihisa Hosoe
  • Patent number: 4145369
    Abstract: Flame-retardant epoxy resin compositions comprising a polyepoxide, an acid anhydride curing agent, an imidazole curing accelerator, aluminum trihydrate powder and red phosphorus powder or red phosphorus powder coated by a thermo-setting resin have a lower viscosity and therefore show a longer pot life and better workability on casting as compared with prior art resin compositions. Also, a fly-back transformer coil produced by casting of said flame-retardant epoxy resin compositions is flame-retardant. Even if it burns slightly, no toxic gas is produced. Therefore, the coil has advantages in that a magnet wire is not corroded and voids are difficult to be formed and thereby partial discharge is difficult to occur, resulting in a long life and a stable output voltage.
    Type: Grant
    Filed: September 19, 1977
    Date of Patent: March 20, 1979
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Hira, Ryoichi Sudo, Issei Takemoto, Tokio Isogai