Abstract
Simulations have been performed to evaluate the effect of a thermal-induced mask on the performance of an optical disk. For simplicity and also so as not to lose generality, we first assume that the thermal-induced mask can be represented by an ellipse with variable shape and a relative position with respect to the center of the readout laser spot. Simulation results reveal that the optical disk exhibits a maximum response when almost half the laser spot is covered by the mask. With a conventional single-beam readout technique, however, this can hardly be achieved. The possibility of achieving this by use of an assistant beam with a modified beam profile is discussed. We show that this method allows us to obtain a maximum response in the track direction without any degradation in the radial direction.
© 1997 Optical Society of America
Full Article | PDF ArticleMore Like This
Jia-Reuy Liu, Pei-Yih Liu, Nai-Yuan Tang, and Han-Ping D. Shieh
Appl. Opt. 37(35) 8187-8194 (1998)
Chubing Peng
Appl. Opt. 40(23) 3922-3931 (2001)
Takaya Tanabe
Appl. Opt. 34(29) 6769-6774 (1995)