This article will analyze key performance parameters such as transmission rate, wavelength, numerical aperture (NA), output power, and receive sensitivity of optical modules. It will also discuss how to choose suitable optical modules based on practical requirements. Transmitter power characterizes the average optical power output from the laser under rated conditions, while receiver sensitivity indicates the minimum. Whether you're selecting an optical transceiver module for short-range multimode applications or long-haul coherent transmission, understanding these parameters ensures reliability and performance. We'll cover everything from physical form factors to spectral characteristics, modulation formats. Optical modules are crucial for today's communication systems as they convert electrical signals into light signals for rapid data transfer. Subsequently, the driver semiconductor laser.