What is an optic fiber coupler? It is an optical device connecting the fiber ends for transmission light waves. These waves are then diverted into different paths. It is capable of combining two or more inputs into a single output and also divides a single input into two or more outputs. The optical coupler is constructed by fusing and tapering the fibers. What does it do otherwise? It splits optical signals between two fibers. The fused coupler is developed using fusing technique and polarization maintaining fiber coupler.
They are manufactured in such a way that a high polarization extinction ratio (PER) is launched along the slow axis of the fiber. Certain applications for PM couplers include optical sensors, optical amplifiers, and fiber gyroscopes. They provide an improved PER (≥20 dB including connectors) and a wide -40 °C to 85 °C operating range. The couplers undergo extensive testing and verification of the PER and they are available with 2.0 mm narrow key FC/PC and FC/PC connectors.
Let us now look at the characteristics and applications for PM Fiber Fused Coupler
- It features Low Insertion Loss
- Also, it has higher extinction ratio
- Available in compact In-Line Packaging
- 100% stability and reliability is ensured
- Uniformity is maintained with high directivity
- The wavelengths vary from 780 nm-2005 nm
- Most preferred for fiber optic instruments and fiber sensors
- Researchers use them in the best possible way and coherent detection is enabled
What is the use of Polarization Maintaining Fiber Coupler?
They are more useful in optical communication and transmission. The availability is in the configuration of 1×2, 2×2, 1×3 (monolithic) and 1×4 (compact cascaded). They are also monolithic in character with operational wavelength up to ±20 nm for 1550 nm region devices. Fused PM splitters are also available on smaller core fibers for various wavelengths like 1064 nm, 980 nm, and other wavelengths.
Additional features of PM Fiber Coupler………..
- Evanescent Wave Coupling
- Compact Silicone Rubber Package
- Advanced wavelength
- Multiple coupling ratios
The IL will be 0.3dB higher and RL will be 5 dB for devices with connectors. The manufacturers of fiber couplers offer custom coupler configurations with other wavelengths, fiber types, coupling ratios, alignment axes, or port configurations. The values are specified with a slow axis launch at room temperature without connectors. The extinction ratio is also specified in the same way and they are aligned to the slow axis of the fiber. The manufacturing process is commended with measurement of the connectors.