Patents by Inventor Shuhji Yaneyama

Shuhji Yaneyama 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).

  • Zoom lens system
    Patent number: 5221995
    Abstract: A zoo comprises, in order from the object side, a first lens group having a positive refractive power that moves along the optical axis for focusing, a second lens group having a negative refractive power that moves along the optical axis for zooming, a third lens group having a negative refractive power that moves along the optical axis for compensating for the image plane that varies upon zooming, and a fixed, imaging fourth lens group having a positive refractive power. The fourth lens group has an aperture and comprises a first sub-group having a positive refractive power and a second sub-group having a positive refractive power, which fourth lens group further satisfies certain conditions.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: June 22, 1993
    Assignee: Asahi Kogaku Kogyo K.K.
    Inventor: Shuhji Yaneyama