Method of molding optical element and optical element molding die

A method of molding an optical element to obtain the molded optical element, the method comprising:

• preparing a die set including an upper die having an upper molding surface, a lower die having a lower molding surface, a side die in which a through hole serving as a side molding surface is formed, and a sleeve configured to accommodate the upper die, the lower die, and the side die;
• disposing a mold material on the lower molding surface after inserting the lower die into the through hole of the side die in order for the lower molding surface to be positioned in the through hole of the side die;
• heating the mold material disposed in the through hole of the side die;
• press molding the mold material with the upper die and the lower die by pushing the side die upward using the lower die to integrally move the side die and the lower die with respect to the upper die and the sleeve in a state where a position of the lower molding surface in the through hole of the side die is maintained at a predetermined position;
• and
• pushing the optical element upward by raising the lower die with respect to the side die and the sleeve to move the lower molding surface in the through hole of the side die to a position which is higher than the predetermined position and at which a part of the optical element after molding protrudes from an upper surface of the side die.