| 摘要 |
PROBLEM TO BE SOLVED: To manufacture an optical disk master disk in which the pit width is reduced while keeping a proper asymmetry value by adding a concave pulse to a recording signal when forming a pit having a prescribed length. SOLUTION: A recording signal generating part 30 generates a recording signal in which the relation between the voltage Vp of the rising and falling of a pulse and at least a part of middle voltage Vm is made into Vm<Vp. A modulation part 9 modulates recording light by using the recording signal generated by the recording signal generating part 30. A glass master disk on which a photoresist is applied is irradiated with recording light. In addition, the relation of Vm<Vp is attained provided that the spot diameter ϕw of the recording light used for the pattern exposure of a pit sequence is in the relation of ϕw>=0.65 ϕr with respect to the spot diameter ϕr of reproducing light. |
