Magnification and resolution of microlenses with different shapes

In this reported work, three types of microlenses, the whole microsphere solid lens (W-SL), the melted microsphere solid lens (M-SL) and the microsphere solid lens semi-immersed in SU-8 resist (S-SL), have been fabricated from mircospheres with a diameter of 2.87 μm. Their imaging properties on the nanosphere arrays with diameters of 280-600 nm were experimentally studied. It was found that the shape of the microlens plays an important role in the imaging properties. The imaging resolution of the S-SL is the best as more high Fourier components of the object can be coupled into the lens, while the magnification (~2.0×) of the M-SL is the largest.