DISK MASTERING PROCESS WITH AN ALL-SOLID-STATE ULTRAVIOLET-LASER

The mastering process of the optical disk is demonstrated using an all -solid-state ultraviolet laser for the first time. A 355-nm emission i s obtained by the nonlinear frequency mixing between 1064 nm and 532 n m using beta-BaB2O4 crystal in an external resonator. The laser head i s efficient hence it does not require welter cooling. A 30% improvemen t over the argon ion gels lasers is obtained in the track pitch variat ion with the 0.74 mu m-pitch-tracks. The absence of the water flow for the cooling is the reason for the improvement. The optics designed at 351 nm turned our to be compatible with the 355-nm laser source.