In this study, a relation between the displacement and the pixels considering the projection distortion which occurs when projecting the 3D displacement of the object onto the 2D image sensor is formulated. T he error caused by the displacement in the longitudinal direction can be suppressed to 10% or less when considering camera posture and a ngle of view A method for estimating the multi point synchronous displacement of bridges during train passage is proposed by using single high resolution camera with w ide angle lens . The proposed method is applied to three actual bridges and compared with the results of Doppler laser displacement sensor s . V ibration modes contributing resonance phenomenon of the entire bridge deformation can be identified by the method.
