The paper develops a virtual simulation experiment system for optical interference and diffraction based on the MATLAB App Designer platform. The system consists of three core modules: optical interference, optical diffraction, and knowledge expansion. The interference and diffraction module provides dynamic demonstrations of theoretical principles, adjustable experimental simulation operations with key parameters, and real-time data processing and result analysis functions. The knowledge expansion module guides students to understand practical applications of interference and diffraction phenomena through case studies (e.g., resolution limits of optical instruments, optical sensors in wearable devices). Featuring visual interfaces, dynamic processes, and interactive exploration, the system transforms abstract theories and complex experiments into intuitive digital teaching resources. It effectively overcomes limitations of traditional teaching and physical experiments, providing strong support for promoting deep learning, enhancing experimental inquiry skills, and fostering innovative thinking.