Calibration Method Applied On Mechanical Precision Of LED Die Quality Inspection Equipment

LED die quality inspection equipment is generally named for machine which is used to probe the optical and electrical parameters of die and then sort them before packa ging. In order to identify the precision of core components and provide credible data related to inspection processes, this equipment need to be calibrated. Data reliability depends on the accuracy of measurement methods and subsequently affect arrangement precision of bin. Improve calibration efficiency is also in favor of industrialization. In this thesis, for the study of calibration methods of mechanical precision of the transfer system, it mainly focus on standardizing the calibration procedures, impro ving accuracy and efficiency. The major content is as follow:First of all, analyzed the specification of mechanical precision calibration based on the process of probe and sort, meanwhile, the structure of electromechanical drive chain was also taken into account. Then, discussed the feasibility of different methods for each item.Proposed a complete solution to X- Y table position deviation test and then analyzed the measurement errors of laser interferometry systematically. With the purpose of reducing both errors due to instrument fix and time for mirror alignments, designed special fixtures for simplification. Then, compensated the axis position error based on PMAC position control system. All these meet the requirements.To determine the position curve of the follower of the eccentric cam mechanism, presented laser triangular surveying and contact measurement respectively. Researched the influence of non-cooperative surface scattering properties on precision of laser triangular measurement and then designed the measuring auxiliary, on the one hand, it ameliorated the scattering properties and on the other hand it achieve the goal to measure different objects on the same station and to adjust quickly the distance between laser head and the target.At last, calibrated the force to pick and place the die by different type of nozzles with the arm which provided credible data for the position and force control.