Optical fiber is considered to be a high-quality carrier for high-speed data transmission due to its high-efficiency transmission capacity. Optical fiber connector assemblies play a very key role in optical fiber communications. Data transmission requires grinding the end face of the connector to maximize its performance. The grinding of the end face of the connector determines its light wave transmission quality. For the vast majority of glass fibers with a cladding diameter greater than 200 microns, end face grinding is a common method to ensure the quality of optical transmission. Generally, the grinding quality is judged by the following five indicators.
ZR Cable Fiber Connector
echo reflection
Currently, the industry standard for echo reflection is <-55dB. Since the expected high data rates encounter data bit errors after signal deformation, this high level of echo reflections will cause system transmission problems that depend on the speed and clarity of the fiber optic system. Usually, what we call a connector is represented by PC, SPC, UPC and APC. These English abbreviations describe the end face type of the connector and are related to the design of echo reflection.
Insertion loss
Insertion loss refers to the amount of power lost when two connectors are mated. Causes of high insertion loss include: misaligned fiber mating, poor connections, and lapping quality of the connector end face. Currently, insertion loss is specified as <0.5db, but the general expectation has become <0.3db.
vertex offset
The "apex" refers to the highest point of the connector end face. Apex Offset is the measured distance between the core and the highest point after the connector has been ground. Excessive vertex offset results in high insertion loss and high echo reflections.
Radius of curvature
The radius of curvature is an indicator of the curvature of the connector end face. An appropriate diameter plus an acceptable amount of fiber recess will optimize fiber-to-connector crimping. The industry specification for the radius of curvature is 10-25mm. This range achieves the maximum performance of the connector.
Fiber sag/protrusion
Sag measures how far the fiber sinks inside the connector pin, however, it is also possible that part of the fiber remains outside the pin. Both of these conditions are directly dependent on the grinding process and can be measured by an interferometer. A typical specification for fiber pitting is greater than 50 nm. Fiber notches can affect return reflection and insertion loss.
When the connector is aligned, the ferrule material around the fiber is compressed, maximizing the tight contact of the fiber with the proper amount of depression/protrusion. There will be air gaps between fibers that are not tightly connected. Air gaps can cause unacceptable values of echo reflections and insertion loss.
