Glass substrate forming mold and production method for glass substrate

A method for manufacturing a glass substrate comprising:

• a first step of placing a glass material in a forming die including a pair of upper and lower dies and a control member for controlling a space between the upper and lower dies;
• a second step of heating and softening the glass material;
• a third step of molding the glass material into a glass substrate in a shape of a parallel plate by pressure;
• a fourth step of cooling the glass substrate;
• and
• a fifth step of taking out the glass substrate,
• wherein a coefficient of thermal expansion of the control member is smaller than a coefficient of thermal expansion of the glass material.

A method for manufacturing a glass substrate comprising:

• a first step of placing a glass material on a saucer;
• a second step of heating and softening the glass material;
• a third step of placing the glass material, which rests on the saucer, in a forming die including a pair of upper and lower dies and a control member for controlling a space between the upper and lower dies;
• a fourth step of molding the glass material into a glass substrate in a shape of a parallel plate by pressure;
• a fifth step of cooling the glass substrate;
• and
• a sixth step of taking out the glass substrate,
• wherein a coefficient of thermal expansion of the control member is smaller than a coefficient of thermal expansion of the glass material.