Results of workpackage 1 – Reliable Precision Tooling Main results obtained so far are listed below: The simulation tool simulates the moulding process at high temperatures enabling a shrinkage error compensation in the range of 1 µm e.g. for aspherical lenses. This not only increases significantly the lens quality, it also reduces the production time dramatically. Typically several iteration loops have to be accomplished in order to compensate geometrical deviations caused by shrinkage. This iterations can be eliminated by applying the developed simulation tool.Ultra precision grinding and diamond turning technologies are the most important processes for the mould manufacturing. This technologies have been developed and several process strategies have been evaluated. Based on this knowledge optimal process strategies have been identified in order to manufacture different geometries in highest accuracies: rotational symmetrical spheres and aspheres, cylindrical lens arrays and diffractive structures. Surface roughness of 5 nm Ra and shape accuracy below 250 nm are reached. Mould coating plays a decisive role regarding the life time of a mould. Therefore a nano-coating facility has successfully been established in order to produce approximately 300 nm thick optical coating. Different coatings are being tested and Pt/Ir has proven to be the most suitable coating material for the optical applications. A nanocrystalline tungsten carbide with grain size of approximately 200 nm and almost no Co binder was developed as a substrate material for the moulds. It has proven its potential and established its position on the mould manufacturing market. All results of WP1 are directly linked to the demonstrator manufacturing in WP7. Therefore the developed manufacturing processes will enable the replicative production of complex glass optics in highest accuracies.
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