Optical element shaping mold set and optical element manufacturing method

An optical element shaping mold set comprising:

• a first shaping mold and a second shaping mold that face each other;
• and
• a tubular third shaping mold which is located around the first shaping mold and the second shaping mold and in which at least one of the first shaping mold and the second shaping mold slides,
• wherein:
• heating, pressing, and cooling are conducted with a shaping-target material accommodated between the first shaping mold and the second shaping mold,
• the third shaping mold has a slit formed on at least one end in a sliding direction of the at least one of the first shaping mold and the second shaping mold,
• the third shaping mold has a linear expansion coefficient that is smaller than a linear expansion coefficient of the first shaping mold and smaller than a linear expansion coefficient of the second shaping mold,
• a clearance exists between the first shaping mold and the third shaping mold and also between the second shaping mold and the third shaping mold when the heating is started, and
• the linear expansion coefficients of the first shaping mold, the second shaping mold, and the third shaping mold are set so that the clearance becomes zero at a temperature for the pressing and a temperature for the cooling.