Patent ID: 8245608

Claim:
A method for making a mold core for molding lenses, the method comprising: providing a first fixture and a mold block, the first fixture defining a first cavity therein, a center of the first fixture located within the first cavity and deviated from a center of the first cavity; providing a lathe comprising a rotatable spindle and a drill bit aligning with the rotatable spindle; installing the blank in the first cavity of the first fixture with a center of the blank aligning with the center of the first cavity, and mounting the first fixture to the spindle with the center of the first fixture aligning with a center of the spindle; machining a first mold cavity in the blank using the drill bit while rotating the first fixture together with the mold block; uninstalling the blank from the first cavity and reinstalling the blank in the first cavity by revolving the blank 180 degrees; and machining a second mold cavity in the blank using the drill bit while rotating the first fixture together with the mold block, thereby obtaining a mold core having the first and the second mold cavities.