A measurement system comprising a light source unit, a projection unit and an optics unit is disclosed. The light source unit is configured to generate a plurality of modulated phase shifted light beams. The projection unit is configured to reflect the modulated phase shifted light beams onto an object surface. The optics unit is configured to capture the modulated phase shifted light beams from the object surface. The measurement system further comprises a photodetector and a processor. The photodetector is configured to receive the modulated phase shifted light beams from the optics unit to generate electrical signals. The processor is configured to retrieve position information of the object surface based on the electrical signals from the photodetector. A measurement method is also presented.