An optical module is mainly composed of optoelectronic devices (including the optical transmitter and optical receiver), functional circuitry, and optical interfaces. Whether in 5G base stations, hyperscale data centers, or long-haul telecom networks, these modules convert electrical signals into optical ones — and back again — to ensure fast, stable, and. An optical module is a component that completes electrical/optical conversion on an optical network. Figure 2-62 shows the structure of an optical module.