| 摘要 |
A non-circular optical disc includes a center hole (21) formed at a center of the optical disc, a clamping portion (22) concentric to the center hole and having a predetermined width, an information storing area portion (24) concentric to the center hole and having a predetermined width, and a non-circular outer shape portion (25) extended along an outer circumference of the information storing area portion, which are formed on a lower surface of the optical disc, and a print layer (26) formed on an upper surface of the optical disc, in which at least two points which are the farthest from the center hole and have the same length exist in the outer shape portion, an outer contact portion (27) corresponds to an inner circumferential surface of a circular disc accommodation groove (17), and the respective neighboring outer contact portions are arranged at an angle of 180¡AE or less with respect to the center point of the center hole. |
