Recent advances in near-field optics: instrumental and applications

We present a recently constructed near field scanning optical microscope. This microscope features an ultrafine tip/sample approach using a 4:1 mechanical gear reduction of an 80 pitch thread giving an effective pitch of 320. The piezo-driven 12 /spl mu/m x-y scan range is complimented by a generous 4 mm coarse mechanical translation range in each direction. The construction materials used in the feedback loop have been carefully chosen for thermal compatibility to reduce differential expansion and contraction between the tip and sample. A novel pressure-fit sample mounting allows for quick and reliable sample exchange.