PREFORM FOR PRECISION PRESS FORMING, FORMING DIE, GLASS COMPACT MANUFACTURING METHOD USING THE DIE, AND OPTICAL ELEMENT MANUFACTURING METHOD

摘要

molten glass lumps in the injury state by cooling and molding glass mold for the molded body to get to the start. The mold is provided with a concave shape with a side wall of the glass molding is installed upright so as to surround the periphery of the bottom and the bottom, the bottom part has a gas ejection port for ejecting a gas for applying a wind pressure to the glass mass portion. By leakage of the molten glass, separating a molten glass mass, and by forming and cooling the glass mass in floating state from the glass forming portion provided in a mold is disclosed a manufacturing method of a glass molded article to obtain a glass shaped body. By using a mold of the present invention, it is possible to mold the preform of the present invention. Having a rotational symmetry, also discloses the two end faces and having one side connected to the outer periphery of the two end faces, the preform for precision press molding of the glass and intersecting the rotational axis of symmetry, respectively. And the two end surfaces of blood press surface, and a plane convex independently or concave surface, having an axis corresponding to the rotational symmetry axis, and when hayeoteul assuming a hypothetical circumference circumscribed to the preform, of the height h of the cylindrical diameter ratio ( / H) is more than one and is less than three, the volume V of the peripheral ₀ ratio (V / V of the volume V of the pre-forms for ₀ ) is not less than 68%. A preform for precision press molding using a press mold is disclosed a method of manufacturing the optical element, which comprises a precision press molding. ; mold, the bottom base member, forming the bottom portion, side wall forming members, the magnet, the inner wall