| 摘要 |
PROBLEM TO BE SOLVED: To facilitate sheet mounting and to improve the dynamic balance of an optical disk after mounting by providing an optical disk substrate with a sheet introducing projection on the side inner than its signal recording surface. SOLUTION: The disk substrate 1 is provided with the sheet introducing projection 3 which projects to the circumference of a central hole 2 and is tapered at its outer periphery on the inner peripheral side of the signal recording part of the substrate. A UV curing resin is dropped onto the front surface on the outer peripheral side thereof and a doughnut-like transparent sheet 5 is mounted thereon. As a result, the misalignment between the sheet 5 and the disk substrate 1 is prevented. A spinner for uniformly developing the UV curing resin 6 and regulating the film thickness to a proper thickness by removing the air bubbles is rotated. The spinner is rotated in the manner described above and at the point of the time the UV curing resin attains the desired thickness, the rotation is stopped and, thereafter, the disk substrate 1 is taken out by holding its outer peripheral end, etc., by a disk substrate take-out device. The disk substrate 1 is transported to a UV curing device and is cured, by which the disk substrate 1 is completed. |
