Investigation of three-dimensional scanning microscope employing adaptive lenses and tunable prisms for zebrafish studies

This thesis introduces, for the first time, an additional scanning technique that combines adaptive lenses and tunable prisms to control the focal spot both axially and laterally. The adaptive lenses with two degrees of freedom allow for compensation of axial focus shift without mechanical movement and for the simultaneous correction of sample-induced aberrations, while the tunable prisms avoid the beam folding issues present in conventional lateral scanning mechanisms, enabling a compact lateral scanning system. However, the demands for monitoring adaptive lenses to achieve desired behavior, particularly for those with large tuning ranges or multiple degrees of freedom, can be high. In this thesis, partitioned aperture wavefront (PAW) sensing is successfully used to characterize a novel adaptive lens that allows for the tuning of focal length and spherical aberrations. To verify the capabilities of adaptive lenses and tunable prisms to be combined with scan objectives, a designed telecentric f-theta scan objective provides a solution. It represents the first successful integration of adaptive lenses and tunable prisms in a compact system utilizing only a single 4F conguration, which minimizes the number of optical components while still achieving 3D scanning. Volumetric measurements of the transgenic fluorescence of the thyroid of a zebrash embryo and mixed pollen grains provide evidence of the volumetric imaging capabilities of this approach. In conclusion, the research based on the control of adaptive lenses and tunable prisms provides a viable solution to improve large-range volumetric imaging in compact transmissive systems. This is also one of the key research focuses of the Biomedical Computational Laser Systems (BIOLAS), enabling flexible 3D scanning.