Quantitative Phase Microscopy (QPM) is a technique frequently used in microscopy togather information about transparent objects that provide a phase shift relative to their background. We propose a technique that employs a liquid crystal in a common-path configuration to provide quasi-real-time 3D information in a single shot. This technique involves using circularly polarized light and a polarized camera to produce 4 images corresponding to 4 different angles of linear polarization. These images can be combined to produce a phase map that contains 3D information about the object. This technique has the benefits of being robust to vibration, space-efficient, and relatively inexpensive.