Exploration of the Diverse Applications of a PM Fiber

A PM fiber, as a high-performance optical fiber material, plays a crucial role in numerous high-tech fields due to its unique polarization-maintaining characteristics.

Interferometers: The Foundation of Precision Measurement

In the application of interferometers, a PM fiber demonstrates its outstanding performance. Interferometers, as precision measurement tools, are widely used in telecommunications, medicine, sensing, and other fields. The introduction of a PM fiber ensures that the light traveling through the signal arm and the reference arm of the interferometer always recombines with the same polarization state, effectively preventing signal attenuation.

This characteristic significantly improves the measurement accuracy of the interferometer. If conventional single-mode fibers are used, the polarization state of the light would vary independently over time, causing the recombined signal to fade between maximum and zero. A PM fiber effectively avoids this issue. Therefore, in optical interferometric measurements, phase modulation, and optical sensing, the application of a PM fiber is key to achieving high-precision measurements.

Fiber Optic Gyroscopes: A High-Precision Model for Rotation Measurement

The fiber optic gyroscope (FOG) is a leader among interferometric optical fiber sensors, and its basic principle is to measure rotational angular velocity using the Sagnac Effect.

The design of the FOG fully demonstrates the primary advantages of optical fibers as intrinsic optical sensing elements: fibers not only guide light but also bend, allowing ultra-long light paths to be confined within a small physical volume. These longer path lengths amplify relatively weak optical effects, creating very compact and high-precision sensors. A typical FOG sensing loop is made up of several hundred to several thousand meters of PM fiber, and its performance is already sufficient to rival the precision of laser gyroscopes. FOGs are widely used in aerospace, marine navigation, and other fields.

Doppler Laser Anemometers and Velocimeters: A New Option for Non-Contact Measurement

Doppler laser velocimeters (Laser Doppler Anemometry, LDV) and wind speed meters use the Doppler shift principle to achieve non-contact measurement of fluid flow velocity. In LDV and wind speed meters, a PM fiber serves as the transmission medium, ensuring stable light transmission and the formation of interference fringes. By measuring the Doppler frequency shift of light scattered from the fluid, the flow velocity can be determined.

This technology has broad application value in wind tunnel experiments, biomedical research, industrial production, and other fields.

With the continuous development of technologies such as the Internet of Things (IoT), artificial intelligence, and big data, the application prospects of a PM fiber will be even broader. Its unique polarization-maintaining characteristics allow a PM fiber to demonstrate extraordinary application potential across various high-tech fields.