| 摘要 |
PURPOSE:To enhance the control accuracy of a developing level and to improve the information reproducibility of the master disk by providing a groove exposing region for monitoring development exposed at the same pitch as the pitch of an information pit region exposed with information pits to the region exclusive of said information pit region. CONSTITUTION:The master disk 1 for the optical disk is formed of the information pit exposing region 2 exposed with the information pits 11, the unexposing region 3, and the groove exposing region 4 for monitoring development where the grooves are exposed at the same pitch as the pitch of the pits 11. The diffracted light of the intensity higher than the intensity of the diffracted light from the region 2 is obtd. if the region 4 is irradiated with an He-Ne laser in order to monitor the developing state. The accurate control of the developing level is, therefore, executed by using the diffracted light from the region 4 as the signal for monitoring the development and the reproducibility of the shape of the information pits on the master disk after the development is enhanced. |
