A standard optical power meter cannot emit light; it only measures optical power, but when combined with a light source in an Optical Loss Test Set, the system can both emit and measure light.

Standard Optical Power Meter Function

An optical power meter (OPM) is designed to measure the power of light signals in fiber optic systems or other optical devices. It typically consists of a calibrated sensor (often a photodiode), a measuring amplifier, and a display to show the optical power in units such as watts or dBm. The OPM detects incoming light and converts it into an electrical signal for measurement, but it does not generate or emit light itself .

Combined Instruments with Light Sources

While a standalone OPM cannot emit light, it is often used in conjunction with a light source—such as a laser or LED—to test fiber optic cables. When the OPM is paired with a light source, the combination is called an Optical Loss Test Set (OLTS). In this setup:

• The light source emits light into one end of the fiber.
• The optical power meter measures the received light at the other end.
• This allows technicians to calculate optical loss and verify the performance of the fiber link . Some advanced instruments may integrate both the power meter and the light source into a single handheld or bench-top device, but the emission of light is always performed by the dedicated light source component, not the power meter itself .

Summary

• Standalone OPM: Measures optical power only; cannot emit light.
• OLTS or combined devices: Include a light source for emission and a power meter for measurement.
• Practical use: The OPM is essential for verifying signal strength, loss, and network performance, but light emission requires a separate or integrated source . In conclusion, if your goal is to emit light for testing purposes, you need a light source; the optical power meter alone cannot perform this function.