Spatially selective fluorescent microscope based on electrically tunable liquid crystal lenses

The use of a large-aperture liquid crystal device in a fluorescent microscope is demonstrated to obtain a spatially selective excitation with an order of magnitude enhancement of the efficiency of the local fluorescence. Better than 1 µm lateral resolution of excitation is achieved by generating local electrically tunable lenses that can be moved to continuously scan the entire field of view. Changing their optical powers also allows for the continuous depth scanning of the excitation point. The proposed approach can be integrated into commercial microscopes as an "add-on" light source.