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In this work, we propose and experimentally demonstrate an improved cylindrical liquid crystal (LC) lens that allows for lateral shifting of the optical axis by use of a simple electrode design. The proposed cylindrical LC lens has potential applications in various fields, such as light sheet imaging, beam shaping, 3D displays, and laser scanning. The lens is composed of two substrates with comb-type electrodes of equal width on their inner surfaces. The comb-type electrodes are arranged in parallel and aligned with each other. Each comb-type electrode is applied with two driving voltages, generating a parabolic and a linear voltage distribution respectively. The voltage difference (VD) between two electrodes contains a quadratic and a linear term, so the symmetrical axis of VD can be shifted by adjusting the four driving voltages. By controlling the VD across the aperture within the linear response region of the LC material, the parabolic VD generates a parabolic phase profile, and the optical axis shifts as the symmetrical axis of VD shifts. The driving method of four voltages to adjust the optical power and the position of the optical axis is described in detail. The combtype electrodes are developed using a standard photolithography process, and a cylindrical LC lens with an aperture width of 2 mm and LC layer of 50 μm is prepared. The results demonstrate that the optical axis can be shifted in the aperture with high precision while maintaining near-ideal phase profiles.
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