Connect the light source and power meter with a high-quality reference cable. Set the reference by pressing “Set Ref” or “Zero” on the meter. This step establishes a 0 dB measurement. Most optical power meters in use today are based on diode sensors made of either silicon, germanium or indium gallium arsenide. Power On: Ensure the device is charged or properly connected to a power source. The working principle of an optical power meter follows a clear sequence: Set the wavelength to match the input. Finding ways to optimize the performance of test equipment is one of the primary issues for managers, yet maintaining a large inventory of test and measurement equipment requires a systematic and efficient approach.