Intelligent Micron Optical Character Recognition of DFB Chip Using Deep Convolutional Neural Network

The microcharacter recognition on the distributed feedback (DFB) laser chip is critically essential but a challenging task for the quality control in the incoming chip inspection and optical device manufacturing lines. Hence, this article proposes, designs, and implements a micro-optical character recognition system based on the microscopic imaging system and deep convolutional neural network to facilitate the microcharacter recognition of DFB chips. The proposed micron optical character recognition (MOCR) contains four components, namely, a microscopic imaging system-based visual-based measurement (VBM), character detection, orientation correction, and character recognition. In particular, data augmentation methods considering limited datasets and some chip character features are studied so as to accommodate complex industrial environments and tiny DFB chips. Experiments from the DFB image dataset of a real optical device manufacturing line showed that it reached the accuracy of 98.8%, which took a high speed of over 12.8 fps coping with DFB chip images, and saved 72% of the labor in the inspection position compared to traditional methods. To the best of our knowledge, there are no existing reports focused on MOCR on DFB chips. So, the first realization and successful application of MOCR played a key role in the intelligent manufacturing and quality traceability of DFB chips and devices in the field of optical communications, which is also of great significance for further accelerating the development of the industrial Internet.