Prof. Harald Giessen: "3D printed microoptics: State of the art and future challenges"

3D printed microoptics: State of the art and future challenges

3D printing using femtosecond lasers gives submicron resolution when polymerizing plastics by two-photon absorption. The small voxel size well below the diffraction limit and the combination with high-speed scanners and high-precision piezo stages allows for the creation of millimeter-sized 3D optics with unprecedented design freedom. We will demonstrate that such complex optics with aspherical and freeform surfaces without rotational symmetry can lead to novel miniature optics with wavefront aberrations as small as lambda/10. Multiple materials can be combined with different refractive indices and dispersions, thus allowing for Fraunhofer-type achromats. Diffractive optics can be 3D printed as well, and stacking several Fresnel-type surfaces leads to aplanatic imaging systems. Hybrids that combine diffractive and refractive surfaces as well as transparent and opaque materials enhance the imaging capabilities even further. When combined with imaging fibers or CMOS imaging sensors, an entire new class of miniature optical devices can be created which will revolutionize augmented and virtual reality as well as self-driving cars. Fiber-based optical trapping, side-looking OCT endoscopes, the smallest imaging endoscope in the world, as well as applications in quantum technology pave the way towards future functionalities and applications [1-9].