3D laser measurement technique of solder paste

A 3D measurement system of solder pastes was established. The system aims to extract the height and other values of solder paste, and realize the quality control of Surface Mount Technology (SMT). 3D laser measurement technique was applied to this system. The calibration process is divided into two steps, the internal parameters of CCD camera are obtained by the RAC method of Tsai, and the laser plane parameters are calibrated with one special multi-arris block. The scanning technique fulfills the acquisition of final 3D profile. Experimental results at the product line prove that the system is a more easily operated device with high performance, and its repeatable precision reaches ±1 µm.