This article provides an in-depth analysis of two key performance indicators of optical modules: transmitter power and receiver sensitivity. The optical module is a core component in optical fiber communication systems, and its performance parameters directly impact the transmission rate, stability, and reliability of the entire system. Transmitter power characterizes the average optical power output from the laser under rated conditions, while receiver sensitivity indicates the minimum. The Transmitter Optical Sub Assembly (TOSA) is responsible for the emission of light. Its primary function entails converting electrical signals into optical signals.