Patents by Inventor Hiromu Umeda

Hiromu Umeda 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: 5875060
    Abstract: A zoom lens system includes, in order from the object side to the image side, a first lens unit, having a negative refractive power, which moves along an optical axis during a zooming operation, a stop diaphragm which moves along the optical axis with the first lens unit at one body during the zooming operation, and a second lens unit having a positive refractive power.
    Type: Grant
    Filed: February 21, 1996
    Date of Patent: February 23, 1999
    Assignee: Minolta Co., Ltd.
    Inventor: Hiromu Umeda
  • Patent number: 5327290
    Abstract: A new compact-size, light-weight and low-cost zoom lens system having a high optical quality with a very simple structure including, from the object side to the image side, a front lens group having a positive refractive power and a rear lens group having a negative refractive power. The zoom lens system is operated by changing the axial air distance between the front and rear lens groups during a zooming operation. The zoom lens system uses aspherical surfaces whose low-cost manufacturing has been enabled by the recent progresses in plastic molding technology and glass molding technology. Many embodiments of the lens compositions according to the present invention, and further more specific examples of the embodiments are described with figures and data that show compactness and high optical performance.
    Type: Grant
    Filed: October 10, 1990
    Date of Patent: July 5, 1994
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Akira Fukushima, Takashi Okada, Junji Hashimura, Hiromu Umeda, Hisayuki Masumoto, Hisashi Tokumaru
  • Patent number: 5249079
    Abstract: A lens system comprises a plurality of lens elements, including a deflecting lens group, to stabilize a blurred image at a focal plane. The deflecting lens group moves slightly in a circular orbit around a predetermined central point on an optical axis of the lens system, resulting in the deflecting lens group being decentered in a direction perpendicular to the optical axis of the lens system and at the same time an optical axis of the deflecting lens group being inclined relative to the optical axis of the lens system.
    Type: Grant
    Filed: August 28, 1990
    Date of Patent: September 28, 1993
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventor: Hiromu Umeda
  • Patent number: 5168403
    Abstract: A zoom lens system comprises from the object side, a front lens group having a refractive power of a predetermined sign and a rear lens group having a refractive power of different sign from that of the front lens group. The front lens group is shiftable along the optical axis of the lens system in a zooming operation, and movable perpendicularly to the optical axis for decreasing a blur caused by a hand shake. The rear lens group is shiftable along the optical axis in the zooming operation.
    Type: Grant
    Filed: December 6, 1990
    Date of Patent: December 1, 1992
    Assignee: Minolta Camera Co., Ltd.
    Inventors: Hiromu Umeda, Akira Fukushima, Takashi Okada, Junji Hashimura, Hisayuki Masumoto
  • Patent number: 5153777
    Abstract: A compact-size, light-weight, low-cost zoom lens system with high optical quality is achieved by using a ray restrictor placed at the most object side of the zoom lens system. In one type, the ray resistor shifts toward the object at a speed different from that of the most object side lens of the zoom lens system as the zoom lens system is zoomed toward the longest focal length, which effectively blocks harmful rays causing coma flare in the peripheral area. In another type, the aperture diameter of the ray restrictor varies according to a zooming operation. The ray restrictor of any type is especially effective when used in a zoom lens system composed of two lens groups. By introducing one or more aspherical surfaces satisfying a certain condition (or conditions) in the zoom lens system, various aberrations are further favorably corrected.
    Type: Grant
    Filed: December 5, 1990
    Date of Patent: October 6, 1992
    Assignee: Minolta Camera Co., Ltd.
    Inventors: Takashi Okada, Akira Fukushima, Hiromu Umeda, Hisashi Tokumaru, Junji Hashimura, Hisayuki Masumoto