Many imaging techniques, such as light sheet microscopy (LSM), require complex light, which has to be generated using special optics. Commonly used are spatial light modulators (SLM). However, they require polarized light, are bulky and are expensive. Therefore, in this work, we propose replacing the SLM by a phase element that generates the desired complex light. Phase elements can be refractive, diffractive or based on meta-optics. We explore optical metasurfaces due to their various advantages. We successfully designed, fabricated and tested an 8-level dielectric, polarization-independent meta- elements that generate Airy and Bessel beams. As there are 8 phase levels, the fabrication needed careful optimization. These results will be presented.
In the second part, we design an element that will generate a Bessel beam with suppressed sidelobes (SBB). Such beams are important, as conventional Bessel beams have sidelobes that lead to photo bleaching while imaging. This SBB has more depth of focus compared to a Gaussian beam and retains the useful properties of the BB, namely its diffraction-free and self-healing nature.