Subwavelength Nano-imaging with a Microbottle Lens

A dielectric microbottle lens constituted by circular glass microcylinder and parabolic-shaped polymer covering layer is demonstrated here. The microbottle lens is fabricated by transferring, wetting and photocuring of UV-curable polymer on a tapered optical microfiber. By using such microbottle lens, periodic grating structures with subwavelength pitch of 360 nm can be imaged in two different imaging modes. When the pitch of the grating structures decreases to 260 nm, clear imaging of the grating structures can only be achieved in the case that the grating stripes are parallel to the microfiber axis of the microbottle lens. The results are analyzed and discussed by finite element simulation.