We discuss the lens distortion of the mobile device camera as one of notes of the proposed synchronization method. Since the method is based on analog physical quantity, the measurement error by a lens distortion directly links to the synchronization error time. A lens distortion is a phenomenon where non-linear displacement according to the distance from the optical axis in the radial direction for an ideal pinhole camera is generated. In our system of augmented TV, processing that a lens distortion affects are as follows: