一种改进的载频交叠重构干涉术在光纤干涉投影三维面形测量中的应用

he Carrier squeezing interferometry (CSI) algorithm based on spatial-temporal fringes can eliminate phase-shifting error of small range. In this paper an improved phase extraction method based on CSI algorithm is proposed, which can eliminate any order phase-shifting error in principle.In this paper, this method was applied in the environmentally sensitive 3-D shape measurement of phase-shifting fiber-optic interferometer projection to eliminate the parasitic fringe caused by phase-shifting error and high-frequency noise caused by interference fringe speckle and so on in test result. The simulation result shows thatthe measurement accuracy of suggested method is near hundred fold than four-step phase shifting method at ±20°random phase error. In addition, we recover surface 100 times in different grades of phase-shifting error to solve averageError Root Mean Square (ERMS) value. For example, in the measuring process of four-step phase shifting method, the ERMS value can be controlled within 1.31×10-3 mm when phase-shifting error of every step is less than ±18°.