Patents by Inventor Ichizo Ogawa

Ichizo Ogawa 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).

  • Method and apparatus for distance measurement using electromagnetic waves
    Patent number: 5044744
    Abstract: Times t.sub.1 and t.sub.2 required for two electromagnetic waves having different wavelengths to propagate from a reference point to a target point are measured. Necessary meteorological conditions along the path are also measured to determine refractivities N.sub.1 and N.sub.2 of the path for the two electromagnetic waves as:N.sub.1 =.alpha..sub.1 .multidot..rho..sub.s +.beta..sub.1 .multidot..rho..sub.wN.sub.2 =.alpha..sub.2 .multidot..rho..sub.s +.beta..sub.2 .multidot..rho..sub.wwhere .rho..sub.s and .rho..sub.w are densities of dry air and water vapor in the path, respectively. Length of the path D is calculated using the following formula:D=[t.sub.1 +{(.alpha..sub.1 +.beta..sub.1 .multidot..rho..sub.w /.rho..sub.s).multidot.(t.sub.2 -t.sub.1)}/{(.alpha..sub.1 +.beta..sub.1 .multidot..rho..sub.w /.rho..sub.s)-(.alpha..sub.2 +.beta..sub.2 .multidot..rho..sub.w /.rho..sub.s)}].multidot.C.where C is the speed of an electromagnetic wave in vacuum.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: September 3, 1991
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Ichizo Ogawa, Yoshihisa Warashina, Yoshihiko Mizushima, Koji Ichie, Morio Takeichi, Akira Takeshima