Fujikura is pushing forward of implementation of the smart factory with AI and IoT for improving the productivity and production quality. In this presentation, we will present visual inspection system incorporating deep learning in the production process of semiconductor lasers. Not only OK/NG classification, but also multiple NG mode classification was performed. The inspection accuracy of 95 % that is equivalent to skilled workers' accuracy was achieved by optimizing the data set and the hyper parameters of a CNN model. The activation map was used for reliability and validity assurance. We will present the difficulty in our practical application in manufacturing industry, such as the small number of some category and small defect/chip size ratio, and also introduce our countermeasures.  Back