近场光存储的深亚微米微型飞行头设计

Ultra submicron flying head design for near-field optical storage

为提高固体浸没透镜(SIL)和盘面之间的近场耦合效率,设计并研制了一种基于流体力学微流动理论的近场光存储深亚微米微型飞行头。建立了承载微飞行头的力学模型,并借助有限体积法对飞行头的动态特性进行了数值仿真。该微型飞行头将聚焦透镜和SIL集成于一个承载微飞行头,克服了光盘高速旋转过程中,二者距离改变而导致离焦的影响;微型飞行头采用了正负压力并存的结构,极大提高了飞行头的承载刚度,并有效消除了工作过程中气流的不断变化对飞行高度的影响,增加了飞行头的动态稳定性;将SIL作为承载微飞行头轨道的设计获得了良好的近场耦合效率。试验表明,微型飞行头在转速18m/s时,承载达到88mN,飞行高度小于65nm,满足近场光存储系统的需要。

A microsize flying head was developed based on the micro fluid theory of hydrodynamics to improve the coupling efficiency between solid immersion lens (SIL) and disk for near-field optical recording. A mechanical model for the head flying characteristics was solved using the finite volume method. The lens and SIL were integrated on the flying head to overcome the defocusing effect during disk rotation. Both positive and negative pressures were generated by the air bearing of the flying head, with the stiffness and motion stability enhanced by the negative pressures. The SIL moves on a rail under the slider which provides sub-micron spacing from the disk surface. The experimental tests were successful with a flying height less than 65 nm from the surface. The carrying capacity exceeded 80 mN. The flying head provides an excellent design for near-field optical systems.