Patents by Inventor Arai Norikazu

Arai Norikazu 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).

  • Objective lens for optical disk
    Patent number: 4613212
    Abstract: An objective lens for an optical disk, particularly a lens of the type which is directly driven for tracking will suffice to be satisfied with a spherical aberration and additional sine conditions. However, it is required that working distance is long and cost is low. These requirements are satisfied by designing an objective lens as a single lens, selecting a shape and thickness of the lens and making one surface thereof aspherical.Let r.sub.1 be the radius of curvature of the lens surface, n the refractive index, f the focal distance, NA the numerical aperture and .DELTA.
    Type: Grant
    Filed: February 12, 1985
    Date of Patent: September 23, 1986
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventor: Arai Norikazu