Mold for producing lens, using mold recesses to aid in lens release
AssigneeHoya Corporation
InventorsShinichiro Hirota, Kishio Sugawara, Kenji Okamura
Life of this patent
Estimating the term…
Abstract
A mold for use in producing a lens comprises a pair of first and second mold portions which are arranged in opposed relation to each other. At least one of the first and second mold portions is movable toward and away from the other. Molding surfaces of the respective first and second mold portions have their respective areas which are located radially outwardly of an effective aperture of the lens. A plurality of recesses are formed in the molding surface of at least one of the first and second mold portions and are located in the area of the molding surface of the at least one mold portion. These recesses separate the lens from the molds.
Claims19
A mold for use in producing a lens having an effective aperture, comprising:
- a pair of first and second mold portions arranged in opposed relation to each other, at least one of said first and second mold portions being movable toward and away from the other, said first and second mold portions having respective molding surfaces, said molding surfaces having respective areas located radially outwardly of the effective aperture of the lens during molding thereof;
- and
- means including a plurality of recesses formed in said molding surface area of at least one of said first and second mold portions for forming, during molding, a plurality of projections on the lens outwardly of its effective aperture whereby shrinkage of the lens during molding causes the projections to ride up respectively in said recesses to establish a gap between the lens and the molding surface of said one mold portion, thereby allowing for easy lens removal from said at least one mold portion.
A mold for use in producing a lens having an effective aperture, comprising:
- a pair of first and second mold portions arranged in opposed relation to each other, at least one of said first and second mold portions being movable toward and away from the other, said first and second mold portions having respective molding surfaces, said molding surfaces each having a respective area located radially outwardly of the effective aperture of the lens;
- a plurality of recesses formed in the molding surface area of at least one of said first and second mold portions;
- and
- said recesses being discontinuous to each other peripherally of said molding surface area of said at least one mold portion.
A mold for producing a concave lens, comprising:
- first and second molding surfaces for molding lens material disposed between said molding surfaces;
- at least one of said first and second molding surfaces being movable toward and away from the other of said first and second molding surfaces;
- at least one of said first and second molding surfaces having means including circumferentially spaced recesses formed therein for receiving the lens material for forming projections, during molding, on the lens material between said molding surfaces whereby shrinkage of the lens during molding causes the projections to move out of said recesses to facilitate removal of the lens from between said first and second molding surfaces.
Dependencies are inferred from the claim text.