Patents by Inventor William E. Seden

William E. Seden 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: 5578332
    Abstract: A mould for cast moulding a contact lens includes a first cup member having a male mould surface and a second cup member with a female mould surface. The two cup members form a piston and cylinder and are used in a pressure vessel so as to apply loading pressure to deflect the mould surfaces to maintain the surfaces in contact with a lens being cast. The mould is opened with the mould surface facing upwardly. Hydrating fluid is added to the first cup member and a cover sealed to the top of the first cup member.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: November 26, 1996
    Assignee: British Technology Group Ltd.
    Inventors: Ronald S. Hamilton, William E. Seden
  • Patent number: 5573108
    Abstract: A mould for cast moulding a contact lens includes a first cup member having a male mould surface and a second cup member with a female mould surface. The two cup members form a piston and cylinder and are used in a pressure vessel so as to apply loading pressure to deflect the mould surfaces to maintain the surfaces in contact with a lens being cast. The mould is opened with the mould surface facing upwardly. Hydrating fluid is added to the first cup member and a cover sealed to the top of the first cup member.
    Type: Grant
    Filed: April 26, 1994
    Date of Patent: November 12, 1996
    Assignee: British Technology Group Ltd.
    Inventors: Ronald S. Hamilton, William E. Seden
  • Patent number: 5293186
    Abstract: To improve its gas-permeability, a contact lens, which may be of any normal material, even a gas-impermeable material such as polymethylmethacrylate, is microperforated with 66000 holes distributed in equispaced sectors leaving unperforated the central (optically important) part and the outermost rim of the lens. With a smaller hole size, some one million holes can be accommodated. In a modification, some or all of the holes go only part way through the thickness of the contact lens.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: March 8, 1994
    Assignee: British Technology Group Ltd.
    Inventors: William E. Seden, Ronald S. Hamilton
  • Patent number: 5143660
    Abstract: A mould for cast moulding a contact lens comprises a first cup member having a male mould surface and a second cup member with a female mould surface. The two cup members form a piston and cylinder and are used in a pressure vessel so as to apply loading pressure to deflect the mould surfaces to maintain the surfaces in contact with a lens being cast. The mould is opened with the mould surface facing upwardly. Hydrating fluid is added to the first cup member and a cover sealed to the top of the first cup member.
    Type: Grant
    Filed: December 3, 1990
    Date of Patent: September 1, 1992
    Assignee: National Research Development Corporation
    Inventors: Ronald S. Hamilton, William E. Seden
  • Patent number: 5036971
    Abstract: A polyolefin mould for casting contact lenses from a polymerizable monomer composition which shrinks on polymerization, said mould comprising: male (50) and female (51) mould halves at least one of which has a flexible diaphragm portion (53, 54) which is shaped to provide a surface corresponding to a lenticular surface, said mould halves (50, 51), when closed together, cooperating to define a mould cavity (52) for receiving a volume of said monomer composition, at least one of said mould halves (50, 51) having a shoulder portion (55, 56) surrounding said cavity and shaped to engage with said other mould half to define an edge moulding portion of said cavity: whereby in use said diaphragm (53, 54) is deflected into said cavity under forces exerted on said mould by said monomer composition when polymerized in said closed cavity (52), thereby compensating for the shrinkage occurring on polymerization and avoiding the formation of bubbles or voids in the resulting lenses.
    Type: Grant
    Filed: December 6, 1989
    Date of Patent: August 6, 1991
    Assignee: CooperVision Optics, Ltd.
    Inventors: William E. Seden, David W. J. Shepherd, Peter Henderson
  • Patent number: 4955580
    Abstract: A polyolefin mould for casting contact lenses from a polymerizable monomer composition which shrinks on polymerization, said mould comprising: male (50) and female (51) mould halves at least one of which has a flexible diaphragm portion (53, 54) which is shaped to provide a surface corresponding to a lenticular surface, said mould halves (50, 51), when closed together, cooperating to define a mould cavity (52) for receiving a volume of said monomer composition, at least one of said mould halves (50, 51) having a shoulder portion (55, 56) surrounding said cavity and shaped to engage with said other mould half to define an edge moulding portion of said cavity; whereby in use said diaphragm (53, 54) is deflected into said cavity under forces exerted on said mould by said monomer composition when polymerized in said closed cavity (52), thereby compensating for the shrinkage occurring on polymerization and avoiding the formation of bubbles or voids in the resulting lenses.
    Type: Grant
    Filed: November 4, 1987
    Date of Patent: September 11, 1990
    Assignee: CooperVision Optics Limited
    Inventors: William E. Seden, David W. J. Shepherd, Peter Henderson