Tunable, Low-Cost, Multi-Channel, Broadband Liquid Crystal Shutter for Fluorescence Imaging in Widefield Microscopy.

Bistable liquid crystal (LC) shutters have attracted much interest due to their low energy consumption and fast response time. In this paper, we demonstrate an electrically tunable/switchable biostable LC light shutter in biological optics through a three-step easy-assembly, inexpensive, multi-channel shutter. The liquid crystal exhibits tunable transparency (100% to 10% compared to the initial light intensity) under different voltages (0 V to 90 V), indicating its tunable potential. By using biomedical images, the response time, resolution, and light intensity changes of the LC under different voltages in three common fluorescence wavelengths are displayed intuitively. Particularly, the shutter's performance in tumor images under the near-infrared band shows its application potential in biomedical imaging fields.