Molding die for optical element with lens-barrel
A molding die for an optical element with a lens-barrel in which the lens-barrel is set in the molding die includes a tubular guide die, a upper die and a lower die sliding in the guide die Also an optical raw material is placed in the lens-barrel and the optical element is sandwiched, heated and pressurized between the upper die having a transfer surface and the lower die having a transfer surface, thereby integrally forming the optical element in the lens-barrel. Outside diameter portions designed to be equal to the inner diameter of the guide die are provided for the upper die and lower die, wherein the outside diameter portion is fitted in the guide die so as to be able to slide only in the axial direction.
1. A molding die for an optical element with lens-barrel being set in the molding die and receiving an optical material, said die comprising:
a tubular guide die;
upper and lower die;
said upper and lower die being axially slidable in said guide die so that center axises of said upper and lower die are coincident with a center axis of said tubular guide and lens-barrel;
outside diameter portions of said upper and lower die equaling an inner diameter of said guide die;
a reference surface being disposed on an outer periphery of a top surface of said lower die for supporting the lens-barrel;
said lower die including an axially and centrally projecting fitting portion, said fitting portion projecting into an inner periphery of said lens-barrel and positioning said lens-barrel, and said reference surface perpendicularly intersecting with an outer peripheral surface of said fitting portion;
a lowermost surface of said upper die and an uppermost surface of said lower die having opposing axially and centrally projecting transfer surfaces, said transfer surfaces respectively projecting into respective upper and lower openings of the lens-barrel and engaging upper and lower surfaces of the optical raw material; and
said upper and lower die sandwiching, heating, and pressurizing the optical element between said transfer surfaces so that the optical element is integrally formed in the lens-barrel.