Assessment of Vacuum Casting Replication Technology for Refractive and Diffractive Micro Opto-Mechanical Components

摘要

In this paper we assess the replication of micro-optical structures through vacuum casting. To that aim we have replicated, besides optical components and structures fabricated with DLP a variety of other optical components: micro-jet lenses, glass gratings, glass lenses and hybrid integrated systems. Shrinkage is always present on the replicated elements and therefore must be compensated in the master element, if one wants to have correct final dimensions. Furthermore it is of great importance that the replica is crystal-clear and without flow lines or other distortions. This can be obtained by tuning the different process parameters and by working with different types and qualities of polyurethane. In this paper we will highlight our findings on the assessment of the vacuum casting technology with respect to shrinkage, replication quality and transmission efficiency.