A spherical artificial compound eye which is comprised of an imaging microlens array and a pinhole array in the focal plane serving as receptor matrix is fabricated. The arrays are patterned on separate spherical bulk lenses by means of a special modified laser lithography system which is capable of generating structures with low shape deviation on curved surfaces. Design considerations of the imaging system are presented as well as the characterization of the comprising elements on curved surfaces, with special attention on the homogeneity over the array. The assembled system is the first spherical compound eye able to capture images. It is evaluated by analyzing resolution and cross-talk between the single channels.

An extensively modified laser-lithography system specially developed for realization of micro-optical profiles on non-planar surfaces is presented. This extended system offers new possibilities of fabricating micro-optical elements without the technology related restriction of surface shape that existed so far. A diffractive lens on a convex spherical substrate is designed and fabricated as an example for hybrid achromatic refractive-diffractive elements to demonstrate the functionality of the system and the wide range of possible new applications.

Laterally displaceable microlens array telescopes allow for variable and fast beam deflection. The generation of spurious light usually leads to a reduction of transfer efficiency with increasing displacement. We present the introduction of an array of field lenses on the back side of a recollimating microlens array that results in a reduced deflection angle dependency of transfer efficiency. A paraxial matrix formalism is used to prove the theoretical elimination of spurious light by use of a field lens array. The fabrication of well-aligned double-sided lens arrays by UV replication is discussed. Measurements of transfer efficiency with and without the use of field lens arrays are compared with the results of numerical wave-optic simulations.

No abstract

No abstract