Modified Fourier transform method for 3D profile measurement without phase unwrapping

An algorithm based on the Fourier transform method without phase unwrapping is proposed to measure the 3D profile of objects. Phase unwrapping is essential and time consuming in conventional fringe projection techniques. To avoid this step, the method utilizes a color fringe pattern to substitute a gray-level fringe pattern. Intensity information can be used to extract the wrapped phase, while color information can be used to calculate the phase shift range. Combining the two parts, real phase value can be obtained without phase unwrapping. Experiments are conducted to verify the feasibility of this method.