| 摘要 |
PURPOSE:To obtain a thin sticking type optical disk with which the parallelism of mounting surfaces for an information recording and reproducing device and information recording and reproducing region surfaces are easily obtainable. CONSTITUTION:A pair of substrates 10a, 10b and hubs 36a, 36b which are vertically symmetrical are stuck to each other via adhesive layers 12. These substrates have clamping zones 14 and format zones 16 having a difference in level. The adhesive layers 12 are disposed only between the format zones 16. Respective flanges 41 of bases 38 of hubs 36a, 36b are interposed between these clamping zones 14. These hubs 36a, 36b are adhered to the corresponding substrates 10a, 10b via the respective flanges 42. The hubs 36a, 36b are not adhered to each other. The information recording and reproducing regions 24 are formed on the inner side of the format zones 16 and the mounting surfaces 22 are formed on the outer side of the clamping zones 14. These surfaces are parallel with each other. |
