Cladding Light Stripper With Transversal Notches For High-Power Fiber Lasers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cladding light strippers for high-power fiber lasers face challenges in efficiently removing cladding light while maintaining even temperature distribution and avoiding overheating, with limitations in power handling capacity and optical power scalability due to the use of high-index polymers and roughened surfaces.
Innovation Solution
A cladding light stripper with transversal notches on the outer surface of the inner cladding allows for controlled light escape and even heat dissipation, using a polymer-free design and an optional heat sink to absorb and dissipate heat, enabling scalable high-power handling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If high-index polymer layers are used to strip cladding light, then cladding light removal efficiency is improved, but temperature distribution becomes uneven and overheating occurs
Solution Approach 1:
The cladding light stripper structure is segmented into multiple functional layers: a polymer layer for light coupling, a notched layer with periodic notches for controlled light extraction, and a heat sink layer for thermal management. This segmentation allows each layer to perform its specific function optimally, distributing the light stripping process along the fiber length rather than concentrating it at one location, thereby improving temperature distribution uniformity while maintaining removal efficiency.
Solution Approach 2:
The notched layer acts as an intermediary between the polymer layer and the heat sink layer. It provides controlled coupling points where cladding light is extracted from the polymer layer and directed toward the heat sink, preventing direct concentrated heating of the polymer while ensuring efficient light removal. The notches mediate the energy transfer process, distributing thermal load across multiple extraction points.
2Productivity
If roughened surfaces are used to strip cladding light, then light removal is achieved, but power handling capacity is limited
Solution Approach 1:
The invention changes the physical parameters of the cladding stripper by introducing periodic notches with controlled depth, width, and spacing. These geometric parameters are optimized to match the modal characteristics of the cladding light, enabling efficient coupling out of cladding modes. The notched structure provides predictable and controllable light extraction compared to random roughening, allowing the device to handle higher power levels by distributing the extraction process across multiple controlled interfaces.
3Reliability
If more cladding light is stripped, then light purity is improved, but heat generation increases causing overheating risks
Solution Approach 1:
The invention converts the harmful effect of cladding light (which needs to be removed for purity) into a beneficial process by implementing controlled extraction at multiple notched locations. The cladding light that would otherwise be wasted or cause heating is systematically extracted through the notched layer and directed to the heat sink, where the thermal energy is managed. This transforms the light stripping process from a potentially harmful concentration of energy into a controlled energy management system that simultaneously achieves purity and thermal management.
Solution Approach 2:
The heat sink layer serves as an intermediary that intercepts the extracted cladding light before it can cause overheating of the polymer or fiber components. By providing a dedicated thermal management interface, the heat sink mediates the energy transfer, allowing high power handling while maintaining component temperatures within safe operating limits.
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
The solution achieves efficient cladding light removal with improved temperature distribution and heat management, allowing for higher optical power handling and flexible control of heat dissipation, reducing the risk of overheating and fiber damage.
Implementation Method 1
cladding light propagates in the much smaller core... The core is doped with ions of a rare-earth element... and is surrounded by the inner cladding, which guides the pump light
Implementation Method 2
an opaque screen or heat sink disposed adjacent the stripped portion of the outer cladding, for absorbing light escaped the inner cladding, and for dissipating heat produced by the absorbed light
Data Source
AI summary
A cladding light stripper may include a double-clad optical fiber having a core for guiding signal light, an inner cladding surrounding the core, and an outer cladding surrounding the inner cladding. The optical fiber may include a stripped portion forming an exposed section. The exposed section may include a plurality of spirally-arranged transversal notches disposed along the optical fiber to enable light to escape the inner cladding upon impinging on the plurality of notches. A circumferential segment of the optical fiber may include a single notch of the plurality of notches. Each of the plurality of notches may have a depth of only a partial distance to the core.