| 摘要 |
PURPOSE:To reduce the influence of the identification signal to the tracking error signal TE and to improve the tracking stability, by providing a continuous groove part between the identification signals which are written into an identification signal part by plural times. CONSTITUTION:A guide track 1 formed by grooves having the optical depth other than lambda/4 is formed to an identification signal part of an optical disk. Then, a continuous groove part 3 of the same forms as the track 1 is formed between an ID1 and an ID2 that wrote twice the identification signals to the identification signal part. At the same time, a guide track 5 is provided between the grooves 7 having the optical depth other than lambda/4 of the optical disk and the ID1 and ID2 to which the identification signals are written twice to the identification signal part according to the presence or absence of a pit 8 having optical depth lambda/4. Then, a continuous groove part 6 of the same form as the track 5 is formed between the ID1 and ID2. The light is transmitted over the identification signal part for detection of a tracking error signal TE. In this case, the residual tracking error DELTAX can be corrected at a part where no groove exists. Thus, it is possible to prevent occurrence of the TE and to improve the tracking stability. |
