A method for inspecting solder dip coating condition of a DIP IC has been developed. In this method, solder dip coating conditions are detected from the reflection intensity of the lighted surface of a lead. For accurate detection, a vision system has been constructed which regards the difference in the inclination of the solder surface as the difference in the intensity of the reflected light.
The system consists of a dichroic mirror and two linear sensors having sources of light which different wavelength for rapid image detection. An IC lead is simultaneously illuminated from the upper left and upper right directions, and the linear sensors take the image of reflected light in each direction. The areas and distributions of the incline and flat regions of the lead are calculated from the intensity of the reflected light.
Using the developed vision system and new inspection algorithm, a prototype inspection system has been developed. The experiments using the prototype system were performed with 1600 samples, and the efficiency of this method has been demonstrated.
J-STAGEがリニューアルされました! https://www.jstage.jst.go.jp/browse/-char/ja/
