Optical Fiber Bundle with Removable Bridging Element for Pump Coupling

Solution Overview

Problem

Existing double-clad fiber devices face challenges in efficiently coupling low-brightness pump sources into the inner cladding without increasing costs, and maintaining stable signal coupling, especially with the adoption of large-mode area or multimode fibers, which requires careful management to avoid core size variations and mode mixing.

Innovation Solution

A bundle of optical fibers is created using a workable and removable longitudinal bridging element that attaches fibers lengthwise, allowing for the integration of pump light injection during manufacturing to minimize core size variations and eliminate separate coupler modules, enabling efficient pump light distribution along the fiber length without additional signal splices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If traditional separate coupler modules are used to couple pump light into double-clad fibers, then pump coupling efficiency can be improved, but device complexity and manufacturing cost increase

Engineering Contradiction:

Improvepump coupling efficiencyVSAvoiddevice complexity

Core Design Contradiction:

Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The patent integrates the pump coupling function directly into the fiber structure by forming a fused bundle of pump fibers and signal fiber during the fiber drawing process itself. This eliminates the need for separate coupler modules that would otherwise be required to couple pump light into the double-clad fiber, thereby reducing device complexity while maintaining pump coupling efficiency.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The pump fibers and signal fiber are bundled and fused together during the preliminary fiber drawing process, before the fiber is deployed in the laser system. This preliminary integration ensures that the pump coupling structure is already in place when the fiber is manufactured, eliminating the need for additional coupling components and assembly steps later.

Inventive Principle:

Principle #10Preliminary action

2Manufacturing precision

If multiple separate manufacturing steps are used to create fiber bundles, then manufacturing precision can be improved, but productivity decreases

Engineering Contradiction:

Improvemanufacturing precisionVSAvoidproductivity

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

The pump fibers and signal fiber are bundled and fused together during the preliminary fiber drawing process, before the fiber is deployed in the laser system. This preliminary integration ensures that the pump coupling structure is already in place when the fiber is manufactured, eliminating the need for additional coupling components and assembly steps later.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent integrates the pump coupling function directly into the fiber structure by forming a fused bundle of pump fibers and signal fiber during the fiber drawing process itself. This eliminates the need for separate coupler modules that would otherwise be required to couple pump light into the double-clad fiber, thereby reducing device complexity while maintaining pump coupling efficiency.

Inventive Principle:

Principle #5Merging (Combining)

3Use of energy by moving object

If additional signal splices are added to integrate pump coupling, then pump light distribution can be improved, but beam quality deteriorates due to core size variations and mode mixing

Engineering Contradiction:

Improvepump light distributionVSAvoidbeam quality

Core Design Contradiction:

Use of energy by moving objectVSManufacturing precision

Solution Approach 1:

The pump fibers and signal fiber are bundled and fused together during the preliminary fiber drawing process, before the fiber is deployed in the laser system. This preliminary integration ensures that the pump coupling structure is already in place when the fiber is manufactured, eliminating the need for additional coupling components and assembly steps later.

Inventive Principle:

Principle #10Preliminary action

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 simplifies and cost-reduces the manufacturing of high-power fiber lasers and amplifiers, enhances beam quality, and allows for efficient energy transfer from pump to signal fibers, while maintaining mechanical stability and reducing operational steps.

Implementation Method 1

at least two of the optical fibers are attached to each other lengthwise by means of at least one longitudinal bridging element

Methodology Applied

Scientific EffectMechanical bonding: Mechanical Fastener

Data Source

PatentUS7813608B2Optical fiber fabrication

Publication Date: 2010.10.12 LIEKKI OY

AI summary

The invention relates to a bundle of optical fibers and a process for its preparation, wherein at least two of the optical fibers are at least partly attached to each other lengthwise by means of a removable longitudinal bridging element. Typically, the bridging element is an open one-hole capillary.