Description
In this work, we use a programmable liquid crystal display spatial light modulator to provide nearly complete polarization control of the undiffracted order for the case where the beam only makes a single pass through the liquid crystal element. This is done by programming and modifying a diffraction grating on the liquid crystal display, providing the amplitude and phase control necessary for polarization control. Experiments show that for the undiffracted order we can create linearly polarized light at nearly any angle, as well as elliptically polarized light. Furthermore, the versatility of the liquid crystal display allows for the screen to be sectioned, which we utilize for the creation of radially polarized-type beams. Such polarization control capabilities could be useful to applications in optical communications or polarimetry. Through the experiments, we also uncover the disadvantages of the single pass system, which include some limitations on the range of linear polarization angles, large intensity variations between different polarization angles, and the inability to create a pure radially polarized beam. These experiments provide a foundation for future work where greater polarization control could be obtained through the use of a dual-pass system, including control of other diffracted orders rather than just the undiffracted order.
