Patent ID: 7593310

Claim:
A method for manufacturing a multilayered disk, the method comprising: forming at least two recording layers in the multilayered disk, wherein a space between the two recoding layers is set to less than 10 μm to refrain from an interference at the adjacent layer when one of the recording layers is recorded or regenerated, and wherein the reflective signal is set to less than D L ⁢ d ⁢ 2 ⁢ ⁢ π ⁢ ⁢ P , D refers to a beam size in a photo detector. L refers to a photo detector size and D/L is set to 0.7, P refers to a ratio of a main light reflected from a layer to access to a noise light reflected from the adjacent layer and is set to less than 1%, and d refers to a space between the recording layers.