A fiber optic coupler may be the optical device that could connect fiber ends for transmission of light waves. These light waves are transferred or diverted into multiple paths and it's effective at combining two or more inputs in to a single output. Also, it divides just one input into two or more outputs.
The fused coupler is employed to split optical signals between two fibers into one and they're constructed by fusing & tapering the fibers together. This approach is useful for making a simple and rugged way of splitting. Polarization maintaining fused coupler is created using unique fusing technique and Polarization Maintaining Coupler maintains fiber.
Characteristic of Polarization Maintaining Fiber Coupler
The operating wavelength of fused PM Splitter is up to ±20 nm for 1550 nm region devices. If you are buying fused coupler for operations within the typical bandwidth or splitter, it is best to order a standard center wavelength. Fused PM splitters may also be on smaller core fibers for various wavelengths like 1064 nm, 980 nm, and other wavelengths. The operating temperature is -5 to +7 and the storage temperature is -40 to +85. The IL will soon be 0.3dB higher and RL will soon be 5 dB for devices with connectors. The connector key and PM fiber are aligned to the slow axis, whereas the fast axis is blocked.
Characteristics and applications for PM Fiber Fused Coupler
1. It incorporates Low Insertion Loss
2. It has high extinction ratio
3. Available in compact In-Line Package
4. It enables high stability and reliability
5. It maintains good uniformity with high directivity
6. Wide variety of wavelengths 780 nm-2005 nm
7. It's useful for fiber optic instruments and fiber sensors
8. It can also be used in research works and enables coherent detection
Optical couplers are important devices in optical communication and there are numerous types of optical couplers with different transmission characteristics. Fused PM splitters have a wide variety of options with the typical configuration of 1x2, 2x2, 1x3 (monolithic) and 1x4 (compact cascaded). They've a monolithic structure which means all of the fibers are fused together. You will find manufacturers developing the PM fused couplers and the coupling ratio may be selected according to the customer's request. They are smaller in dimensions with the low excess loss.