【摘要】 为进一步提高光存储密度,利用固体侵没透镜(SIL)与数值孔径为0.55的长工作距离物镜对飞秒激光脉冲进行聚焦,完成了PMMA及石英介质上的存储实验,并对聚焦物镜焦点与SIL底面离焦时的介质内焦点位置和系统的数值孔径进行了模拟。实验结果表明:当聚焦物镜焦点与SIL底面适当离焦时,实际聚焦在介质内的焦点深度不断加深,且系统的有效数值孔径不断增大。利用这一结果,在距PMMA表面20μm的地方得到了点间距1μm,层间距2.5μm的6层空间点阵;在距石英介质表面15μm的地方获得了点间距为0.6μm,层间距为2.5μm的5层空间点阵,其存储密度可达1.1×1012b its/cm3。更多还原

【Abstract】 Solid immersion lens(SIL) was employed to increase the optical writing density.The position of foci and numerical aperture of the focusing system with SIL were simulated,and the three-dimensional optical data storage was conducted.The simulation result shows that the depth actually focused into the media is increased and the effective numerical aperture is enlarged with the suitable off-focus distance between the foci of focusing objectives and the bottom plane of SIL.With this result,a SIL with n=1.55 was positioned under a 0.55 NA micro objective to focus a 150 fs Ti∶sapphire pulse laser at 800 nm,and a 5-layer reading and writing of data were achieved with 2.5 mm separation between two layers and 0.6 mm separation between two bits.Accordingly,the storage density of 1.1×1012 bit/cm3 was obtained in this way.更多还原