| 摘要 |
PURPOSE:To eliminate eccentricity between a center hole and a tracking guide even when a glass disk is used as a substrate by fitting a plastic in the center hole of the glass disk and boring a center hole for disk driving in the plastic. CONSTITUTION:The tracking guide 2 is arranged on the surface of the glass disk 1 as the substrate. The center hole 3 is bored in the glass disk 1 at the center part and the plastic 6 is fitted in the center hole 3. Then, the center hole 5 for disk driving is bored in the plastic 6. When this center hole 5, a green plastic 6 is fitted in the center hole 3 of the glass disk 1 and adhered fixedly, and while an optical adjustment is made by utilizing the tracking guide so as to obtain concentricity with the tracking guide 2, the plastic 6 is ground to, for example, a 15mm. diameter, thereby suppressing the eccentricity of the center hole 5 for disk driving from the tracking guide 2 to <=100mum. |
