Contact lens mould
AssigneeBritish Technology Group Limited
InventorsRonald S. Hamilton, William E. Seden
Life of this patent
Estimating the term…
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.
Claims9
A mould usable only once in a cast molding operation for cast moulding a contact lens, comprising:
- i) a first mould part comprising
- a first base portion including a male mould surface surrounded by an annular surface defining a trough region on one side of the first base portion,
- an annular wall extending away from said annular surface defining the trough region on said one side of the first base portion,
- a flange extending from an end of said annular wall and adapted for receiving a sealing cover to sealingly cover the contact lens within said first mould part to form a commercial package for said contact lens after said cast moulding operation;
- and
- ii) a second mould part comprising
- a second base having a female mould surface formed on one side thereof, said female mould surface being cooperable with said male mould surface to define a mould cavity therebetween, and
- an annular wall extending perpendicularly from the second base,
- the annular walls of the first and second mould parts being engageable in sliding relation to enable the two mould parts to function as a piston and cylinder to open and close the mould.
Dependencies are inferred from the claim text.