Active and passive components of 3D integrated optics

The potential of 3D integrated optics based on different technological schemes is investigated. Theoretical and experimental results for waveguide geometries with stacked waveguide layers and with waveguide circuits prepared on topological structures are reported as well. Within waveguide geometries including individual guides in a sequence of stacked layers directional coupler arrays allow for short length passive signal distribution, and various schemes of single and multipath switching can be identified. Cost effective preparation technologies as spin coating of polymer and PECVD of SiON layers and their patterning by UV- exposure or RIE, respectively, have been prove to fulfill the critical tolerance requirements of a simultaneous directional coupling in two transversal directions. To realize waveguides with smooth height variation gray scale lithography was used to produce topological surfaces. Upon those surfaces waveguide paths and devices can be defined subsequently, which are useful e.g. for non-planar to planar fan out structures or interferometer configurations for sensing applications. The topological surfaces can be replicated very efficiently by reaction molding, a technology widely used for micro-optical structures, too

Microoptical concepts for miniaturised scanners and switches from design to realisation

We have developed different approaches for optical beam deflection on the base of transmittive microoptical components and miniaturised piezoelectric actuators for high-speed translation of at least one component in the deflection system. Some of these concepts have been further specified for the realisation of special laser beam scanners and fibre optic switches. For these concepts optical design calculations have been performed in order to determine the optimum component parameters of the appropriate microoptical systems. It is very important to know the possibilities of the microoptics technologies when doing the optical design in order to create a realistic microoptical system. Different techniques have been used for the fabrication of the required microoptical components: graytone lithography for one- and two-dimensional rnicroprism arrays, melting resist technique for one- and two-dimensional microlens arrays, precision replication techniques both for cylindrical and spherical le ns arrays and also microprism arrays and ion-beam etching in quartz and silicon. By using optimised microoptical components a series of prototypes for new types of products has been built up and tested with respect to the achievable optical parameters. Special mounting techniques and equipment has been utilised for the system prototype realisation. Considerable effort has to be undertaken in this field for future medium scale production of these systems