OPTICAL ELEMENT FORMING DIE

摘要

PROBLEM TO BE SOLVED: To provide an optical element forming die which allows a good transfer of an asymmetrical optical function surface and facilitates the manufacture of an optical element. SOLUTION: The optical element forming die 1 for forming the optical element having the asymmetrical optical function surface by thrusting a heated preform 4 has an upper die 2 having a transfer surface 24 for forming the optical function surface on the preform 4 and a lower die 3 which has a caving 34 arranged with the preform 4 at a position facing the transfer surface 24, is formed with the side wall part of the cavity 34 to a step form so as to expand the upper die 2 side and of which the surface on the innermost side of the side wall part is an external form reference plane 35 for forming part of the flank of the optical element.