Fiber Laser Aiming System Backward Radiation Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-power industrial fiber lasers face damage from backward-propagating radiation, which existing solutions like WDM devices are costly and inefficient to manage effectively.
Innovation Solution
A fiber laser assembly with a multi-clad fiber optically coupled to a light source, featuring a protective element such as a dichroic filter to reflect or absorb backward-propagating radiation, preventing it from coupling into the light source, thereby reducing damage and maintaining reliable operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a WDM device is used to protect the visible light source from backward-propagating radiation, then the light source is protected from damage, but the device cost and complexity increase significantly
Solution Approach 1:
The patent extracts the protective function from the complex WDM device and implements it using a simple dichroic filter that only needs to reflect the specific laser wavelength while transmitting visible light. This separates the protection function from the costly WDM infrastructure.
Solution Approach 2:
The patent replaces expensive, complex WDM protection devices with inexpensive dichroic filters that can be easily replaced if needed. The filter is a low-cost optical component compared to WDM systems.
2Ease of manufacture
If a dichroic filter is used instead of WDM, then the cost is reduced, but the effectiveness in blocking backward-propagating radiation may be compromised
Solution Approach 1:
The dichroic filter is designed with specific local optical properties - it reflects only the specific laser wavelength (e.g., 1064 nm) while transmitting visible wavelengths. This targeted approach provides effective protection without the need for broad-spectrum WDM functionality.
Solution Approach 2:
The patent changes the optical parameters of the protection element by using a dichroic filter with specific reflectance and transmittance characteristics at different wavelengths. The filter is engineered to have high reflectance at the laser wavelength and high transmittance in the visible range, providing wavelength-selective protection.
3Illumination intensity
If the visible aiming beam power is increased for better alignment visibility, then the alignment capability is improved, but the risk of damage from backward-propagating radiation increases
Solution Approach 1:
The patent converts the potentially harmful backward-propagating radiation into a beneficial reflected beam by using the dichroic filter. The filter reflects the laser wavelength back toward the workpiece area, potentially improving processing while still protecting the light source through the multi-clad fiber architecture.
Solution Approach 2:
The dichroic filter acts as an intermediary element between the visible light source and the backward-propagating radiation. It mediates the interaction by selectively reflecting harmful radiation while allowing the visible aiming beam to pass through for alignment purposes.
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 effectively reduces the power of backward-propagating radiation incident on the visible light source, preventing damage and ensuring the stability of the fiber laser system without the high cost of WDM devices.
Implementation Method 1
a protective element disposed between the light source and the multi-clad fiber so as to prevent a portion of backward-propagating optical radiation at a second wavelength from coupling into the light source
Implementation Method 2
the protective element may be a dichroic filter configured to transmit optical radiation at the first wavelength and to reflect optical radiation at the second wavelength
Implementation Method 3
the multi-clad fiber may be double-clad fiber comprising a core, a cladding and a buffer layer, wherein the core has a higher refractive index than the cladding and the cladding has a higher index than the buffer layer
Data Source
AI summary
A laser assembly comprising a multi-clad fiber optically coupled to a light source configured to emit optical radiation at a first wavelength and a protective element disposed between the light source and the multi-clad fiber so as to prevent a portion of backward-propagating optical radiation at a second wavelength from coupling into the light source.