Sumitomo Electric Industries (SEI) is a leading company in optical communication industry. Its products enable high-capacity data transmission, serving as the foundation of modern communication infrastructure. SEI also develops related equipment and systems like multi-core fibers, high-frequency GaN devices, and access network equipment, and FTTH systems. Its business for future network, such as 5G and 6G, improves mobile network efficiency and performance, meeting rapidly evolving communication demands. Furthermore, SEI contributes to energy-efficient communication networks by promoting sustainable product and technology development.