An optical module usually consists of an optical transmitting device (TOSA, including a laser), an optical receiving device (ROSA, including a photodetector), functional circuits,main control circuit board (PCBA), housing and optical (electrical) interface and other components. The optical module serves as a crucial component in optical fiber communication systems, operating at the physical layer, which is the lowest layer in the OSI model. Its primary function is to achieve optoelectronic conversion by converting electrical signals into optical signals and vice versa. Operating at the physical layer of the OSI model, optical modules are core devices in optical. Optical modules are essential components in modern communication networks, enabling high-speed data transmission over fiber optic cables. As the demand for faster and more reliable internet and data services grows, understanding these devices becomes increasingly important. This guide will explore. The optical module is one of the core devices of the optical communication system, and its development has a vital impact on its related industrial chain, from the upstream industry chip substrate, PCB to the downstream telecom market and data communication market, and the field of lidar driverless. In the era of 5G, AI, and high-speed data centers, optical modules serve as the core bridge for converting electrical signals to optical signals (and vice versa), enabling fast, reliable data transmission across networks. Among various optical module form factors, SFP (Small Form-Factor Pluggable).