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Contactiess embossing of microlenses (CEM) is a new fabrication technique for the production of refractive microlens arrays. The basic idea is that the surface of the microlenses has no contact with the compression molding tool during the shaping of the surface relief. A high precision matrix of holes made by LIGA microfabrication is used as a compression molding tool. This tool is pressed onto a thermoplastic sample which is heated close to the material's transformation temperature. The material bulges into the openings of the molding tool due to the applied pressure. If process conditions are properly set, the material forms lens-like spherical structures. Microlenses and arrays of microlenses with lens diameters between 30 im and 500 im have been fabricated in thermoplastic material (PMMA). Besides highly accurate microlens arrays, CEM also provides the potential of cost-effective production and high precision mounting concepts.