Optical component formation method

Abstract

A method of forming an optical component wherein imperfections in molding the optical component, such as a lens, are removed by: heating an optical material to its plastic state; forming the optical material into the desired shape by employing a mold apparatus and applying a molding pressure; releasing all pressure from the shaped optical material by separating sections of the mold in order to relieve internal stress in the optical material while the optical material is at its plastic state temperature; slowly and controllably reducing the temperature of the optical material. At the time of, or shortly after commencing the slow and controlled reduction in temperature of the optical material, applying a more moderate pressure on the optical material while it is still in its plastic state; either maintaining the moderate pressure on the optical material during its controlled, gradual cooling until a solid state temperature is reached, or alternatively, after a period of time gradually reducing the pressure applied to the mold until a solid state temperature is reached; and, after said solid state temperature is reached, exposing the mold with enclosed optical material to ambient or room temperature without adding heat to thereby rapidly cool the optical material while applying a light pressure on the optical material. A light pressure, corresponding to that produced by the weight of the upper mold when supported by the optical material, can be applied for a time when the optical material is in its plastic state coincident with the molding pressure being released, or application of the molding pressure can be preceded by successive steps of increased pressure. Further, after applying the moderate pressure, the pressure can be gradually relieved as the temperature of the optical material is gradually lowered.