Protein-based soft micro-optics fabricated by femtosecond laser direct writing

摘要

Scientists have used direct laser writing to fabricate flexible and biocompatible optical elements from a protein hydrogel. Yun-Lu Sun and co-workers from Jilin University in China and Pohang University of Science and Technology in Korea say that the miniature optical components produced using this approach could be useful for use in photonic implants or as stretchable optical devices. They fabricated soft, phase-type diffractive lenses with diameters of 50–100 µm by focusing femtosecond pulses from a Ti:sapphire laser into an aqueous ‘protein ink’ comprising a mixture of bovine serum albumin and the photosensitizer methylene blue. Irradiated regions underwent two-photon polymerization to form a soft protein hydrogel. By moving both the laser beam and the sample, the researchers successfully fabricated a three-dimensional optic featuring the desired series of concentric rings needed to act as a phase-type lens.