Contact Lenses can be manufactured by either a mold, or cut by a specially designed lathe.  A contact lens can be given to eye doctors by the manufacturer.  These lenses can come in a finished stage, but if the doctor prefers  to fit the lenses themselves, they can receive semi-finished lenses(lenses that haven't been fitted.

 A semi-finished lens has only the refracting curves, that is the central anterior curve, and the central posterior curve.  Lenses such as these can be molded, or they can be cut on a specially designed lathe.

 There are four molding processes that still exist today.  These four processes are injection molding, casting, compression molding, and sheet forming.  The injection process is done by injecting melted plastic into a mold under pressure.  Casting lenses has a lot of free pouring melted plastic into a mold involved.

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