Utilization of multiphoton absorption has led to important advances in microscopy and photofabrication. Herein, our recent results on precise immobilization of molecules within 3D polymeric matrices by means of multiphoton grafting are presented. Assessment of nonlinear absorption properties of difunctional aromatic azide, selected for this purpose was performed by the Z-scan technique. It indicates that a three-photon absorption process is responsible for photolysis of this compound. Successful photografting for production of 3D patterns with lateral resolution down to 4 µm was achieved. Our results demonstrate the potential of the developed three-photon grafting method for precise 3D site-specific functionalization of different materials.

Abstract-By considering the geometry of the Bennett 3R open-chain linkage it is possible to predict the possible configuration spaces of 6R closed loop mechanisms formed by joining pairs of Bennett linkages. Attention is confined to cases where the configuration space can be described by the intersection of three quadric surfaces in a three-dimensional projective space. There are just five possibilities which contain a component of dimension one. Two of these possibilities correspond to well-known constructions for forming mobile overconstrained 6R mechanisms from Bennett linkages. The geometry shows that these configuration spaces must also contain a number of isolated configurations, a result we believe to be new. Finally we are able to show that one of the other five geometric possibilities cannot occur as the configuration space of a double Bennett mechanism.