摘要 |
A method for producing a record copy disc by cutting a spiral groove into an original provided with a centering formation centered relative to the spiral groove, electrochemically transferring the groove pattern from the original to a master and forming the copy disc from the master, the step of transferring is performed so as to reproduce the centering formation electrochemically on the master, and the step of forming the copy disc is performed so as to form a centering formation on the copy disc from the reproduced centering formation on the master.
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