| 摘要 |
Plastic contact lenses are formed in a casting process in which the required amount of lens-forming material is charged into a mold half, the mating lens half is inserted but only far enough to contact at least the surface of the lens-forming material. Next the inserted part is allowed to dwell or is slowly withdrawn for a sufficient distance to cause the liquid lens-forming material to move to the center of the two molding surfaces and to approximate a column between the two molding surfaces. The moveable mold portion is then quickly inserted into the mold pushing the lens-forming material uniformly outwardly and displacing any air between the two molding surfaces to form a contact lens devoid of air bubbles and entrained air.
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