Patents by Inventor Minoru Imaeda

Minoru Imaeda 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).

  • High sensitivity optical magnetic field sensors having a magnetooptical garnet-type ferrite polycrystal
    Patent number: 5140156
    Abstract: A high sensitivity optomagnetical sensor comprising a light source, a magnetic field-detecting section, a light-receiving section for receiving light emitted from the light source through the magnetic field-detecting section, a measurement-controlling section for controlling the light source, the magnetic field-detecting section, and the light-receiving section, and for measuring an intensity of light received by the light-receiving section, and light transmission paths using optical fibers for optically connecting the light-source section and the magnetic field-detecting section and optically connecting the magnetic field-detecting section and the light-receiving section. The magnetic field-detecting section is constituted by a polarizer, an analyzer and a magnetooptical element arranged between the polarizer and the analyzer. A garnet type ferrite polycrystal is used as a magnetooptical element of the sensor. The ferrite polycrystal has a Verdet constant of not less than 1 deg/cm.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: August 18, 1992
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Imaeda, Emi Asai, Katsunori Okamoto