The depth quality of a time-of-flight (ToF) camera is influenced by many systematic and non-systematic errors<sup>1</sup>. In this paper we present a simple method to correct and reduce these errors and propose a multi-phase approach to improve the depth acquisition accuracy. Compared with traditional calibration methods, we take the position of light source into account, and calibrate the light source together with the camera to reduce depth distortion. To ameliorate the sensor errors caused in the manufacturing process, a Look-up Table (LUT) is used to correct pixel-related errors. Besides, we capture images with multiple phases and apply FFT to get the true depth. By the proposed approach, we are able to reconstruct an accurate 3D model with RMSE of the measured depth belowing 1.2mm.