Process and Installation for Molding an Optical Lens

摘要

The object of the invention is a process for molding an optical element such as a lens ( 2 ). According to the invention, the element is obtained by a reaction injection molding process comprising the steps of mixing at least two polymerizing reactants and forcing the obtained reacting mixture by an injection duct ( 5 ) for filling under pressure a scaled mold cavity ( 4 ) having an entry side ( 43 ) provided with a casting opening ( 42 ) and an evacuation side ( 44 ) and providing a laminated flow of mixture in a spout ( 6 ) having a progressive enlarging transversal section between the outlet opening ( 52 ) of the injection duct ( 5 ) and the casting opening ( 42 ) of the mold cavity ( 4 ), for avoiding any turbulent area in said laminated flow, said evacuation side ( 44 ) being provided with means ( 45 ) for evacuating air contained in the mixture during mold filling. The invention also covers the molding installation adapted for using such a process.