Cumming Benjamin P, Debbarma Sukanta, Luther-Davis Barry, Gu Min
Centre for Micro-Photonics and CUDOS, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, Hawthorn, Australia.
Opt Express. 2013 Aug 12;21(16):19135-41. doi: 10.1364/OE.21.019135.
One of the challenges in laser direct writing with a high numerical-aperture objective is the severe axial focal elongation and the pronounced effect of the refractive-index mismatch aberration. We present the simultaneous compensation for the refractive-index mismatch aberration and the focal elongation in three-dimensional laser nanofabrication by a high numerical-aperture objective. By the use of circularly polarized beam illumination and a spatial light modulator, a complex and dynamic slit pupil aperture can be produced to engineer the focal spot. Such a beam shaping method can result in circularly symmetric fabrication along the lateral directions as well as the dynamic compensation for the refractive-index mismatch aberration even when the laser beam is focused into the material of a refractive index up to 2.35.
使用高数值孔径物镜进行激光直写时面临的挑战之一是严重的轴向焦伸长和折射率失配像差的显著影响。我们展示了通过高数值孔径物镜在三维激光纳米加工中对折射率失配像差和焦伸长的同时补偿。通过使用圆偏振光束照明和空间光调制器，可以产生复杂的动态狭缝光瞳孔径来设计焦斑。这种光束整形方法即使在激光束聚焦到折射率高达2.35的材料中时，也能实现沿横向的圆对称加工以及对折射率失配像差的动态补偿。
