Polarization Beam Combining for Higher-Power Wavelength Lasers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a demand for further increase in the output power and power density of laser beams combined through wavelength beam combining.
Innovation Solution
A wavelength beam combining device that includes a polarization beam splitter to separate laser beams into polarized components, polarization conversion elements to align polarization directions, and diffraction gratings to coaxially combine beams, followed by a polarization combiner to generate a third wavelength-combined beam, enhancing output power and power density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If conventional wavelength beam combining is used to combine multiple laser beams, then optical output power is increased, but further increase in output power and power density is limited
Solution Approach 1:
The patent segments the laser beams into two orthogonal polarization groups (first and second polarized light beams). Each group is processed separately through dedicated diffraction gratings to generate first and second wavelength-combined beams, which are then recombined. This segmentation allows independent optimization of each polarization channel, enabling further power scaling beyond conventional single-channel combining.
Solution Approach 2:
The patent utilizes the polarization dimension as an additional degree of freedom for beam combining. By employing orthogonal polarization states and corresponding polarization conversion elements, the system combines beams not only in spatial overlap but also in polarization space, effectively doubling the combining capacity and achieving higher output power and power density.
2Power
If multiple laser beams are combined through wavelength beam combining, then output power increases, but power density enhancement is insufficient
Solution Approach 1:
The patent merges multiple laser beams into a single coaxial beam through a polarization beam combiner after separate diffraction grating processing. The first and second wavelength-combined beams, each containing multiple wavelengths, are combined into one output beam, concentrating both power and power density in a single spatial location for enhanced laser processing capability.
3Productivity
If polarization conversion elements are added to align polarization directions, then beam combining efficiency is improved, but device complexity increases
Solution Approach 1:
The patent introduces polarization conversion elements as intermediary components between the polarization beam splitter and the diffraction gratings. These intermediaries convert the polarization states to ensure proper alignment for subsequent diffraction and combining processes, acting as mediators that enable efficient beam combination while maintaining a systematic and modular device architecture.
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 device effectively enhances the output power and power density of combined laser beams by optimizing polarization and diffraction processes, allowing for improved laser processing applications.
Implementation Method 1
a polarization beam splitter configured to separate the plurality of laser beams into a plurality of first polarized light beams linearly polarized in a first polarization direction and a plurality of second polarized light beams linearly polarized in a second polarization direction
Implementation Method 2
at least one diffraction grating configured to diffract the plurality of first polarized light beams and generate a first wavelength-combined beam into which the plurality of first polarized light beams are coaxially combined
Data Source
AI summary
A wavelength beam combining device includes: a polarization beam splitter configured to separate the plurality of laser beams into a plurality of first polarized light beams linearly polarized in a first polarization direction and a plurality of second polarized light beams linearly polarized in a second polarization direction that is orthogonal to the first polarization direction; a first polarization conversion element configured to convert the second polarized light beams into a plurality of third polarized light beams linearly polarized in the first polarization direction; a diffraction grating configured to diffract the plurality of first polarized light beams and generate a coaxially combined first wavelength-combined beam, and to diffract the plurality of third polarized light beams and generate a coaxially combined second wavelength-combined beam; and a polarization beam combiner configured to generate and emit a third wavelength-combined beam into which the first wavelength-combined beam and the second wavelength-combined beam have been coaxially combined.