How does the magnitude of drawing tension affect the residual stress and geometry of the fiber?
The magnitude of drawing tension significantly influences both the residual stress and geometry of an optical fiber during the drawing process.
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Residual Stress: Higher drawing tension generally leads to increased residual tensile stress within the fiber, particularly in the core and cladding regions. This occurs because the fiber is stretched and rapidly cooled under tension, “freezing in” the strained state. Elevated residual tensile stress can impact the fiber’s mechanical strength, making it more susceptible to fracture, and can also induce birefringence, affecting its optical transmission properties. Conversely, lower tension can result in less residual stress, potentially improving mechanical reliability.
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Geometry: Drawing tension primarily affects the fiber’s diameter. Given a constant preform feed rate and drawing speed, increased tension will cause the molten glass to be drawn more thinly, resulting in a reduced fiber diameter. Conversely, lower tension will lead to a larger diameter. Precise control of drawing tension is crucial for maintaining the consistent target diameter, as well as the circularity and concentricity of the fiber’s core and cladding. Deviations can lead to increased optical losses and poor splicing performance.
OFSCN offers a range of high-quality optical fibers, some of which are designed with specific geometric and mechanical properties for various applications:
- OFSCN® G.652D Optical Fiber
- OFSCN® G.657 Optical Fiber
- OFSCN® 120℃ SM High-temperature Optical Fiber
- OFSCN® Gold-coated Optical Fiber
Here is an image of an OFSCN optical fiber:
