| 摘要 |
PURPOSE:To form a disk of a uniform thickness and prevent a dispersion of the quality of a disk by a method wherein a back plate of a required board thickness is detachably provided on the opposite surface to a cavity surface of each of a stationary mirror platen and a movable mirror platen for correcting the thickness of these mirror platens. CONSTITUTION:A stationary mirror platen block 26 is composed of a stationary mirror platen 24 and a back plate 20, both of which can be attached/detached through a bolt 22. Similarly, a movable mirror platen block 48 is composed of a movable mirror platen 42 and a back plate 46, both of which can be attached/detached through a bolt 44. For example, if a cavity surface 28 of the stationary mirror platen 24 is damaged and repaired by grinding and polishing, the thickness of the stationary mirror platen 24 is reduced by an amount t1. However, only by replacing the back plate 20 with a back plate 20a increasing in board thickness by the reduced amount, a dimension D between cavity surfaces 28 and 56 is not changed. In addition, this mold can correspond to a need for changing a thickness of a disk to be molded only by replacing the back plates 20, 46. |
