To measure the opening (split ratio) of a 1:8 optical splitter, use an optical power meter and a calibrated reference cable to measure the optical power at each output port relative to the input.

Step-by-Step Measurement

1. Prepare Equipment
   • Optical power meter calibrated for the splitter's operating wavelength (typically 1310 nm or 1550 nm)
   • Launch/reference fiber cable
   • The 1:8 optical splitter to be tested
2. Set Up the Test
   • Connect the launch cable to the optical source and calibrate the power meter to set a 0 dB reference at the input.
   • Connect the input of the splitter to the launch cable.
3. Measure Each Output Port
   • Connect the power meter to the first output port and record the optical power.
   • Repeat for all eight output ports. Each port should ideally receive 1/8th of the input power for a uniform 1:8 split .
4. Calculate Split Ratio and Insertion Loss
   • Split Ratio (SR): $SR=\frac{P_i}{P_t}\times 100\%$, where $P_i$ is the power at a single output port and $P_t$ is the total input power .
   • Insertion Loss: Compare the measured output power to the expected ideal split. Excess loss includes manufacturing losses and connector losses .
5. Optional Tests
   • Test at multiple wavelengths to check wavelength dependence.
   • Compare outputs to ensure uniformity.
   • Check for crosstalk by applying a signal to one output and observing other outputs .

Practical Notes

• PLC splitters provide highly uniform splits, while FBT splitters may have slight variations.
• Always use clean connectors and calibrated equipment to minimize measurement errors .
• Document the measured values for each port to verify compliance with specifications and for network planning purposes. By following this method, you can accurately determine the split ratio and insertion loss of a 1:8 optical splitter, ensuring proper performance in a passive optical network.