Abstract: The phase measurement deflection technique can measure the surface shape of mirror and specular objects with high accuracy,but for transparent objects with high transmittance and large curvature,only part of the surface shape can be measured based on the principle of reflection.At the same time,the effect of parasitic reflection on the rear surface should be eliminated.For a transparent object with large curvature,two methods,normal consistency constraint and refraction parallax,are proposed based on the measurement principle of（PMD）and stereo vision to complete the 3D surface measurement.The measurement system consists of two cameras and a monitor which displays sinusoidal grating.First,the stereo system is calibrated,and the internal and external parameters are obtained.Then,a tested transparent object is placed between the display and the cameras,and the position of the deflected light caused by the tested object can be obtained by the phase-shifting technique.If the light rays deflect only once and the refractive index of the object is known,the 3-D shape of the object can be calculated according to the principle of stereo vision and the normal consistency.In the computer simulation,the upper surface shape of the plano-convex lens with focal length of 242.857 1 mm is restored,and the reconstruction error is distributed in ±5 μm.Computer simulation confirms these feasibility.The feasibility of the proposed method is further verified by the preliminary measurement of the object.This method is especially suitable for the measurement of 3-D shape of transparent objects with large curvature.