Polarization Corrector for Femtosecond Laser Beam Power Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Femtosecond laser systems used for cutting corneas or lenses face a reduction in modulated laser beam power due to polarization variations when the photonic crystal fiber's position and orientation change, affecting the shaping system's efficiency.
Innovation Solution
Incorporating a polarization corrector upstream of the shaping system to measure and compensate for polarization variations in the laser beam, ensuring the polarization at the shaping system input matches a desired reference polarization, thus maintaining the beam's power regardless of the system's position or orientation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the photonic crystal fiber's position and orientation change to adapt to different system configurations, then the system's adaptability is improved, but the polarization of the laser beam varies, causing reduction in modulated laser beam power
Solution Approach 1:
The patent implements a feedback mechanism where the polarization state of the laser beam is continuously monitored after passing through the photonic crystal fiber, and the polarization controller adjusts the polarization state based on this feedback to maintain optimal power levels at the shaping system input, resolving the contradiction between system adaptability and power maintenance
Solution Approach 2:
The patent dynamically changes the polarization parameter of the laser beam using a polarization controller that adjusts the polarization state in response to position and orientation changes of the photonic crystal fiber, thereby maintaining consistent modulated laser beam power across different system configurations
2Device complexity
If the photonic crystal fiber is used to transmit the laser beam over distance, then the device complexity is reduced by facilitating transmission, but the polarization variation induces reduction in modulated laser beam power
Solution Approach 1:
The patent introduces a polarization controller as an intermediary component between the photonic crystal fiber and the shaping system. This mediator compensates for polarization variations introduced by the fiber, ensuring that the modulated laser beam maintains its power levels while still benefiting from the transmission facilitation provided by the optical coupler
3Manufacturing precision
If the shaping system is made sensitive to polarization for precise control, then the manufacturing precision is improved, but the system becomes vulnerable to polarization variations causing power reduction
Solution Approach 1:
The patent applies preliminary action by adjusting the polarization state of the laser beam before it enters the shaping system. The polarization controller pre-compensates for any polarization variations that may occur in the photonic crystal fiber, ensuring that the shaping system receives optimally polarized light and maintains both precision and power levels
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 solution maintains the full power of the modulated laser beam at the shaping system's output, enhancing cutting efficiency and precision by stabilizing the laser beam's polarization, regardless of the system's position or orientation.
Implementation Method 1
the optical coupler including a photonic crystal optical fiber for filtering the LASER beam 11 from the femtosecond LASER source 1
Implementation Method 2
the optical coupler including a photonic crystal optical fiber
Implementation Method 3
a polarization corrector for modifying the polarization of the processing LASER beam upstream of the shaping system
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
The present invention relates to a cutting device comprising: - a laser source (1) for emitting an initial laser beam (11) in the form of pulses, - a shaping system (2) positioned downstream of the femtosecond laser (1), for transforming the initial laser beam (11) into a single phase-modulated laser beam, - an optical coupler (3) between the laser source (1) and the shaping system (2), the optical coupler (3) including an optical fibre (31), remarkable in that the cutting device further comprises a polarisation corrector (7) for modifying the polarisation of the initial laser beam (11) at an input end of the optical coupler (3) such that the polarisation of the laser beam at an output end of the optical coupler (3) corresponds to a desired reference polarisation.