Executing Organisation: AiF Projekt GmbH, Program: ZIM – Central Innovation Program SME of the Federal Ministry of Economic Affairs and Energy
The aim of the project is the development, implementation and validation of a process chain for the individualized production of hydrophilic intraocular lenses (IOL) by means of two-photon polymerization (2PP). The three success factors are (i) a reliable computation of geometry data for “on-site” production of an individualized IOL, (ii) suitable storable 2PP processable monomer mixtures preformulated in polymerization cells, and (iii) a laser based 2PP system that can meet the high geometric requirements of the IOLs. The final IOL prototypes must meet all the requirements for a medical device. Finally, a production in the clinic (“on site”) will be developed and investigated.
For the development of the laser-assisted 2PP system, a femtosecond laser (Origami-10 XP) with a wavelength of 515 nm, a microscope objective with a NA of 0.75 and a high-precision positioning system are used. To selectively polymerize the liquid sample in the laser focus by the effect of two-photon absorption, the femtosecond laser pulses are focused into the material which is actually transparent for the green wavelength. By positioning the laser focus relative to the sample, finally, any three-dimensional structure can be generated. Subsequently, the not-used, still liquid material is removed by a developer solution.
Previous results indicate that three-dimensional structures can be generated by the use of medium NA microscope objectives for two-photon polymerization. Die in der untenstehenden Abbildung gezeigten Strukturen wurden aus einem Hybridpolymer (ORMOCER®) erzeugt, welches Acrylate als organisch vernetzbare Gruppen enthält.