Fabrication of a micro-lens array with a nonlayered method in projection microstereolithography

A fabrication method which is to make micro-lens arrays (MLAs) without a stacking process in projection microstereolithography is described. This method has two merits. First, the fabrication time can be reduced due to the use of one cross-sectional image. Second, the surface quality can be improved due to non-layer fabrication. A photocurable resin, which has low yellowing for adaption to a micro-lens, is synthesized. For precise fabrication of micro-lens arrays, the fabrication condition is estimated through curing experiments. Each micro-lens of the array is individually fabricated with a specific exposure time because the light intensity is not uniformly distributed. To verify this method, micro-lens arrays are fabricated in various dimensions. The limitations of such fabrication are also investigated.

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