An inspection system is provided. The inspection system comprises a light source, a grating, a phase shifting unit, an imager, and a processor. The light source is configured to generate light. The grating is in a path of the generated light and is configured to produce a grating image after the light passes through the grating. The phase shifting unit is configured to form and reflect a plurality of phase shifted patterns of the grating image onto an object surface to form a plurality of projected phase shifting patterns. The imager is configured to obtain image data of the projected phase shifted patterns. The processor is configured to reconstruct the object surface from the image data. An inspection method and a phase shifting projector are also presented.