Patents by Inventor Tadafumi Sakata

Tadafumi Sakata 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: 9751793
    Abstract: A method of manufacturing a glass molded product includes the steps of preparing a lower die including a lower die surface and a space forming surface formed to extend downward away from an outer edge end portion of the lower die surface with the outer edge end portion being defined as a starting point, preparing an outer frame including an annularly formed inner circumferential surface, arranging the lower die on an inner side of the outer frame, dropping a prescribed amount of molten glass droplet onto the lower die surface such that a surface of the molten glass droplet connects the outer edge end portion and a portion of the inner circumferential surface located above a position of the outer edge end portion to each other and the molten glass droplet does not wet-spread over the space forming surface, and pressurizing and molding the molten glass droplet.
    Type: Grant
    Filed: May 9, 2013
    Date of Patent: September 5, 2017
    Assignee: KONICA MINOLTA, INC.
    Inventors: Kazuyuki Ogura, Yoshihiro Kamada, Tadafumi Sakata
  • Patent number: 9156196
    Abstract: Provided is a method for manufacturing optical elements, the method including the following processes: a process to determine the wave-front aberration for a lens fabricated using a reference die, and then choose the integer multiple of a predetermined constant that is closest to the difference between a lens design value and the wave-front aberration for the lens fabricated using the reference die; and a process to determine the amount of aberration correction that cancels out the aforementioned integer multiple aberration, change the lens design so that either the low-order spherical aberration or the low-order astigmatism therefor becomes equal to the aberration correction, and fabricate a correction die from either a first or a second die, with the shape of the molding surface thereof changed on the basis of the changed design value. Then the die design value is decided upon, yielding a final die.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: October 13, 2015
    Assignee: KONICA MINOLTA OPTO, INC.
    Inventors: Tadafumi Sakata, Youichi Ogawa, Kazunari Tada
  • Publication number: 20150135771
    Abstract: A method of manufacturing a glass molded product includes the steps of preparing a lower die including a lower die surface and a space forming surface formed to extend downward away from an outer edge end portion of the lower die surface with the outer edge end portion being defined as a starting point, preparing an outer frame including an annularly formed inner circumferential surface, arranging the lower die on an inner side of the outer frame, dropping a prescribed amount of molten glass droplet onto the lower die surface such that a surface of the molten glass droplet connects the outer edge end portion and a portion of the inner circumferential surface located above a position of the outer edge end portion to each other and the molten glass droplet does not wet-spread over the space forming surface, and pressurizing and molding the molten glass droplet.
    Type: Application
    Filed: May 9, 2013
    Publication date: May 21, 2015
    Inventors: Kazuyuki Ogura, Yoshihiro Kamada, Tadafumi Sakata
  • Publication number: 20120007262
    Abstract: Provided is a method for manufacturing optical elements, the method including the following processes: a process to determine the wave-front aberration for a lens fabricated using a reference die, and then choose the integer multiple of a predetermined constant that is closest to the difference between a lens design value and the wave-front aberration for the lens fabricated using the reference die; and a process to determine the amount of aberration correction that cancels out the aforementioned integer multiple aberration, change the lens design so that either the low-order spherical aberration or the low-order astigmatism therefor becomes equal to the aberration correction, and fabricate a correction die from either a first or a second die, with the shape of the molding surface thereof changed on the basis of the changed design value. Then the die design value is decided upon, yielding a final die.
    Type: Application
    Filed: March 11, 2010
    Publication date: January 12, 2012
    Inventors: Tadafumi Sakata, Youichi Ogawa, Kazunari Tada
  • Publication number: 20110016920
    Abstract: In an optical element manufacturing method for press molding in which primary molten glass droplets are caused to collide with a plate to separate some of the droplets and fine droplets of a secondary molten glass that have passed through an opening are dropped onto a lower die to perform press molding, by setting the diameter of the opening of the plate in the range of 50-100% of the effective diameter of the optical functional surface provided for the lower die, manufacturing conditions for the secondary molten glass droplets can be set easily and properly, and optical elements with satisfactory quality of both appearance and optical performance can be manufactured reliably.
    Type: Application
    Filed: March 24, 2009
    Publication date: January 27, 2011
    Applicant: Konica Minolta Opto, Inc.
    Inventors: Shunichi Hayamizu, Tadafumi Sakata
  • Publication number: 20100192635
    Abstract: A molding die with a simple structure, which produces an optical element of a low eccentricity degree, without narrowing the option for materials of the molding die and a method for producing an optical element by using the molding die are provided. The molding die includes a top die, bottom die, guiding member having a guiding surface kept in contact with the side faces of the top die and bottom die during the press molding of glass material, an expansion member for pressing the top die and bottom die against the guiding surface by thermal expansion by heating, and a supporting member for supporting the guiding member and expansion member. Among these members, the expansion member has the greatest thermal expansion coefficient. The press molding is applied to the glass material while the top die and bottom die are pressed against the guiding member by the thermal expansion of the expansion member.
    Type: Application
    Filed: July 22, 2008
    Publication date: August 5, 2010
    Inventor: Tadafumi Sakata
  • Patent number: 7415842
    Abstract: The present invention relates to a manufacturing method for an optical glass element, in which molten glass 9 is pressed between a lower mold 1 and an upper mold 8, and the pressing process is carried out while maintaining a space 10 between a border area (5, 6) of a molding face 2 belonging to the lower mold 1 and a circumferential face 3 located on the periphery thereof and glass 9, and an optical glass element manufactured by such a method.
    Type: Grant
    Filed: September 14, 2004
    Date of Patent: August 26, 2008
    Assignee: Konica Minolta Opto, Inc.
    Inventors: Tadafumi Sakata, Tadashi Sugiyama
  • Publication number: 20070180861
    Abstract: A preform is supplied between a pair of molding dies, followed by heating, softening and pressing. A smallest radius of curvature in the preform is smaller than a radius of a globular member having a volume equal to that of the preform. In this fabricating method, -an abutment portion between the molding die and the preform is located at a curved surface or the center of the molding die, thereby preventing any local abutment of the preform against the molding die.
    Type: Application
    Filed: January 22, 2007
    Publication date: August 9, 2007
    Applicant: KONICA MINOLTA OPTO, INC.
    Inventors: Shunichi Hayamizu, Tadafumi Sakata, Tadashi Sugiyama
  • Publication number: 20070157669
    Abstract: A manufacturing apparatus of a glass product, comprising: a plurality of lower molds; a nozzle for allowing a molten glass droplet to drop therefrom; and a shifting unit for successively shifting any one of lower molds, selected among the lower molds, to a dropping position at which the molten glass droplet drops from the nozzle in synchronized timing with dropping of the molten glass droplet, which can efficiently press-mold molten glass droplets that are allowed to drop from a nozzle of a melting tank; and a manufacturing method applied to the apparatus.
    Type: Application
    Filed: January 10, 2007
    Publication date: July 12, 2007
    Inventors: Shunichi Hayamizu, Yoshihiro Kamada, Tadafumi Sakata
  • Publication number: 20050247081
    Abstract: The present invention relates to a manufacturing method for an optical glass element, in which molten glass 9 is pressed between a lower mold 1 and an upper mold 8, and the pressing process is carried out while maintaining a space 10 between a border area (5, 6) of a molding face 2 belonging to the lower mold 1 and a circumferential face 3 located on the periphery thereof and glass 9, and an optical glass element manufactured by such a method.
    Type: Application
    Filed: September 14, 2004
    Publication date: November 10, 2005
    Inventors: Tadafumi Sakata, Tadashi Sugiyama
  • Patent number: 6707026
    Abstract: An SIM (solid immersion mirror) made principally of a light-permeable high-refractive-index medium has a lower surface which is produced by rotating a parabola about a symmetry axis, and an upper surface which is a perpendicular bisector surface of a line segment connecting the vertex and the focus of the parabola. The upper surface has the property of transmitting collimated light incident in a direction perpendicular thereto and reflecting the light reflected from the lower surface. Such a structure of the SIM facilitates the design of the upper surface and the lower surface both of which are reflecting surfaces, and allows the light to be incident on a light focusing point uniformly from therearound, thereby to form a proper light spot at the light focusing point. Additionally, the SIM allows the light to enter the medium through the entire upper surface, to achieve effective use of light.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: March 16, 2004
    Assignee: Minolta Co., Ltd.
    Inventors: Hiroshi Hatano, Tomoko Miyaura, Tadafumi Sakata
  • Publication number: 20020014575
    Abstract: An SIM (solid immersion mirror) made principally of a light-permeable high-refractive-index medium has a lower surface which is produced by rotating a parabola about a symmetry axis, and an upper surface which is a perpendicular bisector surface of a line segment connecting the vertex and the focus of the parabola. The upper surface has the property of transmitting collimated light incident in a direction perpendicular thereto and reflecting the light reflected from the lower surface. Such a structure of the SIM facilitates the design of the upper surface and the lower surface both of which are reflecting surfaces, and allows the light to be incident on a light focusing point uniformly from therearound, thereby to form a proper light spot at the light focusing point. Additionally, the SIM allows the light to enter the medium through the entire upper surface, to achieve effective use of light.
    Type: Application
    Filed: July 31, 2001
    Publication date: February 7, 2002
    Inventors: Hiroshi Hatano, Tomoko Miyaura, Tadafumi Sakata