Abstract
We propose a dual step mu-3D printing (two-photon lithography) strategy, which is the 3D version of the classic lithography etching-mask strategy, to achieve selective gold metallization for the realization of reflective micro-optics. We apply this strategy to obtain right-angle prism micro-mirrors used to create dynamic counterpropagating optical traps for biological samples in a holographic optical trapping setup with a single low-NA objective. We print the prisms on standard glass coverslips to create integrated optical trapping chips. We show the automatization of alignment between prisms and masks by a computer vision software.