Patents by Inventor Junichi Ohmoto

Junichi Ohmoto 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 and image pickup apparatus having the same
    Patent number: 8441738
    Abstract: A zoom lens includes, in order from the object side to the image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a rear group including one or more lens units. An aperture stop is included on the image side of the second lens unit, and the second lens unit and at least one of the lens units included in the rear group move during zooming. The Abbe number ?dj1 and the partial dispersion ratio ?gFj1 of a material of a refractive optical element j1 having a negative refractive power included in the second lens unit, the focal length fj1 of the refractive optical element j1, the focal length f2 of the second lens unit, and the anomalous partial dispersion ratio ??gFj1 of the refractive optical element j1 are set appropriately.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: May 14, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Junichi Ohmoto
  • ZOOM LENS AND IMAGE PICKUP APPARATUS HAVING THE SAME
    Publication number: 20120200940
    Abstract: A zoom lens includes, in order from the object side to the image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a rear group including one or more lens units. An aperture stop is included on the image side of the second lens unit, and the second lens unit and at least one of the lens units included in the rear group move during zooming. The Abbe number ?dj1 and the partial dispersion ratio ?gFj1 of a material of a refractive optical element j1 having a negative refractive power included in the second lens unit, the focal length fj1 of the refractive optical element j1, the focal length f2 of the second lens unit, and the anomalous partial dispersion ratio ??gFj1 of the refractive optical element j1 are set appropriately.
    Type: Application
    Filed: February 2, 2012
    Publication date: August 9, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Junichi Ohmoto