Introduction of PM Fiber and PM Fiber Assemblies

What is PM Fiber?

Polarization-maintaining fiber, abbreviated as PM fiber, is a special type of optical fiber that can maintain the polarization state of light in fiber optic communication and sensing systems. The design and manufacturing of this fiber aim to address the issue where the polarization state of traditional optical fibers is easily affected by external factors such as temperature, bending, and stretching during transmission. The principle and application of PM fiber represent a significant breakthrough in the field of fiber optic technology, greatly expanding the application scope of optical fiber technology and improving the stability and performance of the system.

The Principle of PM Fiber

The working principle of PM fiber is based on the phenomenon of birefringence. Ideally, the circular symmetrical structure of the fiber would not produce birefringence, meaning light would travel at the same speed in any polarization state. However, in practice, fibers exhibit birefringence due to manufacturing defects or external factors, causing changes in the polarization state of light. PM fiber introduces strong birefringence through special design treatments, thereby offsetting the effects of external factors on the polarization state of light.

Manufacturing of PM Fiber

There are two main methods for manufacturing PM fiber: stress type and shape type. Stress-type PM fiber achieves birefringence by introducing geometrically asymmetric stress within the fiber core, usually accomplished by incorporating stress rods made of different glass assemblies on either side of the fiber core. Shape-type PM fiber achieves birefringence by using an elliptical core shape, which generates a certain degree of birefringence even without mechanical stress.

The Structure of PM Fiber

The structure of PM fiber mainly includes elliptical cladding, bow-tie, and panda types. These structures maintain the light's polarization state through specific designs. For example, the panda-type PM fiber embeds specific stress rods in the fiber core to form a strong birefringence effect, thus maintaining polarization stability.

Applications of PM Fiber

PM fiber has a wide range of applications in various fields. In fiber optic communication systems, PM fiber can be used for connections between lasers and modulators because modulators typically require input light with a specific polarization state. Moreover, PM fiber is widely used in fiber optic sensing technologies, such as fiber gyroscopes and hydrophones, which are highly sensitive to polarization states. PM fiber can also be used in interferometers and fiber lasers, where polarization stability is crucial for improving system performance.

MEISU's Fiber Assemblies

MEISU offers a series of custom optical assemblies, including 2D fiber arrays, linear fiber arrays, PM fiber assemblies, high-temperature optical elements, and optical switches for coherent optical communication, sensing, biophotonics, and quantum communication. As a leading manufacturer of PM fiber assemblies, MEISU provides PM fiber assemblies designed for high-performance interference sensors, integrated optics, and communication.

MEISU's fiber assemblies are increasingly being applied in fields beyond traditional optical communication. MEISU will continue to strive to develop new optical devices to meet and lead market trends, providing more solutions for customers. From standard universal SM fiber arrays initially used for PLC splitters to custom-designed 2D fiber arrays for astronomical optics, from simply packaged items to sealed and high-temperature resistant items, MEISU will continue to explore and progress.