Optical Fiber Draw Tension Control for Axial Uniformity
Solution Overview
Problem
Conventional optical fiber manufacturing processes face challenges in achieving axial uniformity of optical properties due to variations in process steps like soot deposition, making it difficult to reduce axial variations in optical fibers, which affects manufacturing yield and costs.
Innovation Solution
A method involving the use of a time-varying draw tension during the fiber drawing process to reduce axial variations in optical properties, where a reference optical fiber is drawn with constant tension, and the tuned optical fiber is drawn using a varying tension to minimize property variations along the fiber length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional soot deposition process is used to form preform, then manufacturing cost is reduced, but axial variation in optical properties increases
Solution Approach 1:
The patent applies parameter changes by varying the draw tension during the fiber drawing process to compensate for axial variations in the preform. By dynamically adjusting the draw tension parameter, the method compensates for non-uniformities in soot deposition, thereby reducing axial variations in optical properties without requiring more expensive deposition processes.
2Manufacturing precision
If constant draw tension is used during fiber drawing, then process simplicity is maintained, but axial variation in optical properties increases
Solution Approach 1:
The patent implements dynamics by transitioning from constant draw tension to time-varying draw tension control. The draw tension is dynamically adjusted during the fiber drawing process based on the axial position, allowing compensation for preform non-uniformities. This dynamic control approach improves optical property uniformity while adding manageable system complexity.
Solution Approach 2:
The method employs feedback control by measuring the actual draw tension and comparing it with the target time-varying tension profile. The feedback loop adjusts the draw tension in real-time to maintain the desired profile, ensuring accurate compensation for axial variations in the preform and improving manufacturing precision.
3Productivity
If multiple burners are used in deposition subsystem, then deposition rate increases, but non-uniformity in soot deposition increases
Solution Approach 1:
The patent applies preliminary anti-action by proactively compensating for the non-uniformities introduced by multiple burners. Instead of trying to eliminate the non-uniformities at the deposition stage, the method applies a counteracting measure during fiber drawing by using time-varying draw tension to offset the axial variations caused by non-uniform soot deposition, thereby recovering manufacturing precision while maintaining high productivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively reduces axial variations in optical properties, improving manufacturing yield and reducing costs by ensuring consistent optical fiber quality over longer lengths.
Implementation Method 1
using a time-varying draw tension, the time-varying draw tension reducing the variation in the optical property as a function of axial position
Data Source
AI summary
A method of manufacturing a tuned optical fiber includes providing a first preform from a set of like preforms each having substantially the same refractive index profile, including amount of axial variation relative to a target refractive index profile. The method includes drawing a reference optical fiber from the first preform and measuring a variation in an optical or physical property as a function of axial position. The method also includes drawing from a second preform from the set of like preforms the tuned optical fiber. The drawing includes using a time-varying tension that reduces the amount of variation of the optical or physical property of interest. The time-varying tension is defined by an amount of axial stress imparted to the tuned fiber needed to alter the refractive index profile and the at least one optical or physical property based on a stress-optic effect.