MERATE (LC) – Bachelor/Master – Technological thesis – Direct laser writing on thiol based photopolymer for tailored holographic patterns

Thiol based photopolymer is a simple and effective substrate for holographic optical elements (HOEs).
The possibility to use the direct laser writing (DLW) to transfer the patterns is highly desirable because it is highly versatile and it allows for obtaining different computer generated holograms with different functionalities on the same substrate. This approach can be efficiently exploited in integrated optics and sensors.

The goal of this thesis work is the optimization of the writing conditions to have holograms with high efficiency and good pattern fidelity.
The writing speed, irradiance and duty cycle are optimized. Target holograms are gratings, Fresnel lenses, both symmetric and grayscale patterns.
The holograms are characterized in terms of diffraction efficiency, morphology (AFM) and composition (UV-vis and vibrational spectroscopy).

[Image Credit: INAF-OAB]