Which side of the optical module is the receiving end

The receiving end of an optical module is the ROSA (Receiver Optical Sub-Assembly) side, which converts incoming optical signals into electrical signals.Overview of Optical Module StructureAn optical module typically has two main functional sides:Transmitting end (Tx): Contains the TOSA (Transmitter Optical Sub-Assembly), which converts electrical signals into optical signals for transmission over fiber.Receiving end (Rx): Contains the ROSA (Receiver Optical Sub-Assembly), which includes a photodiode and associated circuitry to convert incoming optical signals back into electrical signals for the system . The module also has an electrical interface that connects to the host system and an optical interface that connects to the fiber optic cable .Identifying the Receiving EndThe receiving end can be identified by the following characteristics:ROSA assembly: Contains a photodetector (PD) and a transimpedance amplifier (TIA) that converts light into voltage signals .Optical port labeling: Many modules label the ports as "Rx" for receive and "Tx" for transmit. Correct polarity requires connecting the Tx of one device to the Rx of the other .Function in the network: The Rx port is where the module receives optical signals from the fiber, which are then processed internally and sent to the host system as electrical signals .Polarity ConsiderationsIn fiber optic networks, proper alignment of Tx and Rx is critical. The receiving end of the module must be connected to the transmitting end of the opposite device to ensure correct signal flow. Misalignment can cause data errors or network downtime .SummaryTo summarize, the receiving end of an optical module is the ROSA side, which is responsible for converting incoming optical signals into electrical signals. It is typically labeled as "Rx" and must be connected to the transmitting end (Tx) of the corresponding device to maintain proper polarity and ensure reliable data transmission .