| 摘要 |
PURPOSE:To obtain the excellent recording disk with less birefringence and high bit density made of plastic by reducing the outer diameter of a forming body when/after said forming body is formed by presurizing with the stamper having, on the surface, information signal formed by recesses and proteusions. CONSTITUTION:The formed body which preliminarily has a larger diameter than the final diameter of a disk and is provided with the central hole for a spindle in center, is formed by pressurizing by using a mother model having information signal formed by recesses and protrusions on its surface. Then, at forming or after forming, the peripheral part of the disk is cut off by melting cut or machining cut, and the outer diameter of the disk is reduced, whereby the disk with less birefringence and high bit density is obtained. |
