Measurement of Optical Power & Loss

   
          There is a difference between the power coupled into a component like a cable or a connector and the power that is transmitted through it. This difference is what we call optical loss and defines the performance of a cable, connector, splice, etc.

• Measuring power

Power in a fibre optic system is like voltage in an electrical circuit. To measure power, attach the meter to the cable that has the output you want to measure. Turn on the transmitter/source and note the power the meter measures.

• Testing Loss

Following two methods are used to measure loss. Optical Loss Test Sets houses a light source and power meter in the same unit. For both methods two units of loss test sets (one at each end of the fibre under test) are required.

• Single Ended Loss (Laser Source and Power Meter)

This test is initiated from one end and result is displayed at far end unit.

• Double Ended Loss (FasTest Method)

In this test Laser source is initiated from one end and the results are displayed at both ends simultaneously.