Three-dimensional biodegradable structures fabricated by two-photon polymerization.

Two-photon polymerization has been employed to fabricate three-dimensional structures using the biodegradable triblock copolymer poly(epsilon-caprolactone-co-trimethylenecarbonate)-b-poly(ethylene glycol)-b-poly(epsilon-caprolactone-co-trimethylenecarbonate) with 4,4'-bis(diethylamino)benzophenone as the photoinitiator. The fabricated structures were of good quality and had four micron resolution. Initial cytotoxicity tests show that the material does not affect cell proliferation.

Shrinkage of microstructures produced by two-photon polymerization of Zr-based hybrid photosensitive materials.

An investigation of the shrinking behaviour of a zirconium-based sol-gel composite micro-structured by two-photon polymerization is presented and a simple, straightforward methodology allowing the evaluation of shrinkage is suggested. It is shown that volume reduction is directly related to the average laser power (irradiation dose) used for the microfabrication and becomes a critical issue near the polymerization threshold. It is demonstrated that this shrinkage can be employed beneficially to improve the structural resolution.

Micro lens fabrication by means of femtosecond two photon photopolymerization.

We report the fabrication of micro lens using an alternative annular scanning mode with continuous variable layer thickness by two-photon polymerization after multi-parameter optimization. Laser scanning mode and scanning pace parameter are optimized to achieve good appearance. As examples of the results, a 2 x 2 micro spherical lens array with diameter of 15 microm and a micro Fresnel lens with diameter of 17 microm are fabricated.