Calibration Method for Line Structured Light Vision Sensor Based on Vanish Points and Lines

Line structured light vision sensor (LSLVS) calibration is to establish the location relationship between the camera and the light plane projector. This paper proposes a geometrical calibration method of LSLVS based on the property of vanish points and lines, by randomly moving the planar target. This method contains two steps, (1) the vanish point of the light stripe projected by the light plane is found in each target image, and all the obtained vanish points form the vanish line of the light plane, which is helpful to determine the normal of the light plane. (2) one 3D feature point on the light plane is acquired (one is enough, surely can be more than one) to determine d parameter of the light plane. Then the equation of the light plane under the camera coordinate system can be solved out. Computer simulations and real experiments have been carried out to validate our method, and the result of the real calibration reaches the accuracy of 0.141mm within the view field of about 300mm×200mm.