This paper presents a new design of a wide angle augmented reality (AR) system and an effective registration method using a single image. The AR system is designed to meet three requirements: (1) the field of view (FOV) of the AR system must be wide enough to view reference constructions in outdoor scenes; (2) the precise registration of virtual objects should be guaranteed at any position of the image; and (3) the registration should be valid after motion of the camera. We use camera calibration and calibration-free methodologies in our approach. The internal parameters of the camera are determined roughly by the camera calibration and how the distortion coefficient of the camera lens is refined. The external parameters are determined by the calibration-free approach. At least four coplanar points forming a projected parallelogram are needed to construct the affine coordinates that are used for the registration. The only presumed condition is that the user specifies some projected parallelogram lines of the reference object interactively. The experimental results demonstrate the display prototype of the wide angle AR system with the distorted images removed and registration of 3D virtual models in static and dynamic camera environments.