Patent ID: 8087264

Claim:
An apparatus for forming a glass substrate for an information recording medium, the apparatus comprising: a first die having a mounting surface for mounting molten glass; and a second die having a flat press surface for pressing glass so as to face the mounting surface, wherein the second die includes: a heat exchange chamber, a part of the inner wall of the heat exchange chamber being an opposite press surface for cooling the press surface; and a heat-exchanging-fluid-introducing tube that introduces a heat-exchanging fluid for exchanging heat with a part that surrounds the heat exchange chamber, the tube connecting an outside of the apparatus for forming a glass substrate to a substantial center of the opposite press surface, and the second die is constructed such that a wall thickness of the opposite press surface decreases continuously or stepwisely from an outside of the opposite press surface to an inside of the opposite press surface, in a direction perpendicular to the press surface.