Enhancing and up-scaling of integrated photonic 4F convolution neural networks

Convolution neural networks (CNNs) have garnered significant attention in today's digital world due to their remarkable ability to analyze medical images, recognize speech, translate languages, and make intelligent decisions. However, the convolution operation, which plays a vital role in neural networks, imposes a high computational cost, increasing power consumption and latency, particularly when dealing with large matrices. Integrated photonics presents an exciting opportunity to drastically accelerate CNNs with its virtual O(1) cost and speed-of-light latency, by leveraging the properties of Fourier optics. In this study, we propose the design, fabrication and testing of an integrated photonic system for convolutional neural networks based on the 4F system. Moreover, we introduce an innovative backscattering method to accurately adjust the phase of each micro-disk modulator (MDM), ensuring precise on-chip Fourier transform operations. Furthermore, we demonstrate the system's potential for achieving higher speeds through its scalability with multiple wavelengths and optical buffers.