Polymer microlens fabrication techniques that enable easy integration with VCSELs are presented. We have developed a high-tolerance coupling structure with microlenses formed on both sides of the optical components for inter-chip optical interconnections, and have developed two types of drop-on- demand techniques for producing microlenses: an ink-jetting method and a dispensing method. Both methods use the surface tension of liquid UV-curable epoxy polymer. We have fabricated various microlenses that have a geometrical diameter from 20 $mu@m to over 1 mm with F/1 to F/12 by controlling the volume and viscosity of the droplets and their wettability to the substrate. The measured uniformity in arrayed lenses was within $POM 1 percent in lens diameter and $POM 3 $mu@m in pitch. Examples of how we have integrated microlenses with VCSELs are also presented. An ink-jetted microlens ona VCSEL coupled to a single-mode fiber enabled highly efficient coupling: 4 dB greater than without the microlens. A dispensed microlens on a VCSEL coupled to a multimode fiber increased the coupling efficiency by 20 dB compared to without a microlens. In the multimode case, large tolerances of $POM 2 mm in axial misalignment and $POM 10 $mu@m in lateral misalignment were obtained for a coupling loss increase of 1 dB.
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