An optical module typically consists of an optical transmitter (TOSA, Transmitter Optical Sub-Assembly, containing a laser diode), an optical receiver (ROSA, Receiver Optical Sub-Assembly, containing a photodetector), functional circuits, and optical (electrical) interfaces. The working principle of optical modules is illustrated in the diagram shown in the Optical Module Working Principle Diagram. Optical modules typically have an electrical interface on the side that connects to the inside of the system and an optical interface on the side that connects to the outside. 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. An optical module works at the physical layer of the OSI model and is one of the core components in the fiber communication. Modern communication networks rely on optical transceivers to transfer data at the speed of light.
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