The most commonly used single point active alignment method (SPAAM) is based on a static pinhole camera model, in which it is assumed that both the eye and the HMD are fixed. This leads to a limitation for calibration precision. In this work, we propose a dynamic pinhole camera model according to the fact that the human eye would experience an obvious displacement over the whole calibration process. Based on such a camera model, we propose a new calibration data acquisition method called the region-induced data enhancement (RIDE) to revise the calibration data. The experimental results prove that the proposed dynamic model performs better than the traditional static model in actual calibration.