Resin Molded Article For Optical Element Manufacturing Apparatus And Method Of The Same

A manufacturing apparatus of a resin molded article for an optical element, having a first mold, a second mold removable in a mold clamping direction with respect to the first mold, and a movable part movable in the mold clamping direction and a direction opposite to the mold clamping direction with respect to one of the first mold and the second mold, wherein the resin molded article for the optical element having a hollow section inside is formed by injecting a molten resin in a cavity configured with the first mold, the second mold and the movable part, the manufacturing apparatus, comprising:

• a pressurized fluid charging device to charge a pressurized fluid into the molten resin injected into the cavity to form the hollow section;
• and
• a bias member to bias the movable part in the mold clamping direction,
• wherein by charging the pressurized fluid into the cavity, an inside mold pressure is increased so as to move the movable part in the opposite direction to the mold clamping direction with respect to the first mold or the second mold against a bias force of the bias member, and by discharging he pressurized fluid in the cavity the inside mold pressure is decreased so as to move the movable part in the mold clamping direction with respect to the first mold or the second mold by the bias force of the bias member.