Methods, devices, and systems for injection molding contact lenses

摘要

Methods, devices, and systems for manufacturing ophthalmic lenses using direct injection molding are described. The present methods, devices, and systems include a mold block having a first mold insert and a second mold insert defining a lens-shaped cavity between them. A raised non-uniform region that projects into the lens-shaped cavity is incorporated in a peripheral zone of the molding surface of at least one of the mold inserts. When an ophthalmic lens is formed using the described mold block, at least one depression is produced in the lens. A gate placed at the non-uniform region allows the depression to hide any gate witness that may form when the mold is closed or separated.

主权项

1. A method of manufacturing a contact lens, comprising:
providing a first mold insert comprising a body section; said first mold insert comprising a lens forming surface including a raised non-uniform region having an opening formed through the lens forming surface in the location of the raised non-uniform region, and a fluid channel passing through the body section and in fluid communication with the opening; placing the first mold insert into a mold block so that the lens forming surface of the first mold insert and the raised non-uniform region form part of a lens-shaped cavity; providing a lens forming composition through the fluid channel and the opening so that an amount of the lens forming composition is deposited in the lens-shaped cavity; allowing the lens forming composition to form a contact lens body retaining the shape of the lens-shaped cavity; removing the contact lens body from the mold block and the mold insert; washing the contact lens body; inspecting the contact lens body; placing the contact lens body in a package with a packaging solution; sealing the package containing the contact lens body and the packaging solution; and sterilizing the package containing the contact lens body and the packaging solution to produce a finished contact lens.