Patent ID: 7718098

Claim:
A method of obtaining an optical lens from a polymerizable material, comprising: providing a mold ( 1 ) that is formed of two facing and spaced shells ( 2 , 3 ) and an annular seal ( 4 ) comprising means ( 10 , 11 ) for cooperating with the periphery of said shells ( 2 , 3 ) to define a molding cavity, said seal ( 4 ) being adapted to be compressed elastically when said shells ( 2 , 3 ) are moved toward each other; filling said molding cavity with said polymerizable material; polymerizing the material filling the molding cavity; prior to the polymerizing the material filling the molding cavity, applying an external mechanical force to move said shells toward each other; and prior to the polymerizing, releasing said force, the force producing a compression of the seal ( 4 ) and the shells ( 2 , 3 ), wherein a filling hole ( 19 ) is provided in said annular seal ( 4 ), away from said means ( 10 , 11 ) for cooperating with the periphery of the shells ( 2 , 3 ), in that during said filling stage said material is introduced into the cavity through said filling hole ( 19 ), and in that said material is introduced after said step of applying a mechanical external force to move said shells toward each other and before said step of releasing said force, wherein a plug ( 5 ) is provided for plugging said filling hole ( 19 ) in said seal ( 4 ) and said filling step comprises, after introducing said material and before said step of releasing said force, a step of plugging said filling hole ( 19 ) with said plug ( 5 ), the only hole in said annular seal ( 4 ) is said filling hole ( 19 ), and said filling hole comprises a first section ( 21 ) and a second section ( 22 ), the first section ( 21 ) extending between a first end opening into said molding cavity and a second end at which it is joined to a first end of said second section ( 22 ), in that said plug ( 5 ) is provided for plugging said filling hole and comprises a body ( 25 ) having a first portion adapted to fit tightly into said first section ( 21 ) of the filling hole ( 19 ) to plug the filling hole ( 19 ), and the body ( 25 ) of the plug ( 5 ) has a second portion to define with said second section ( 22 ) of the filling hole ( 19 ) a chamber ( 26 ) around said second portion of the body ( 25 ), with said first portion of the body ( 25 ) having a free end, and in that said cavity and said first section ( 21 ) of the hole ( 19 ) are filled during said step of introducing the polymerizable material into the cavity.