Patent ID: 9481596
Filing Date: 2016-11-01
CPC Classification: C03B

Claim Text:
1. An optical element manufacturing method, comprising: placing an optical material in a cavity of a mold comprising upper and lower dies, the upper die exerting a self weight on the optical material; during a first period, exerting a first weight, greater than the self weight exerted by the upper die, on the optical material while the optical material is positioned in the cavity between the upper die and the lower die; during a second period, heating and softening the optical material by introducing a heated gas into the cavity at a first flow rate; and during a third time period, molding the optical material into the optical element by exerting a second weight, larger than the first weight, on the optical material while introducing the heated gas into the cavity at a second flow rate which is higher than the first flow rate; wherein the heated gas is introduced into the cavity during the second time period by moving a movable gas nozzle from a first position remote from the cavity to a second position closer to the cavity than the first position.