Microaxicon Beam Forming Lens for Homogeneous Laser Cutting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laser machining heads struggle to achieve optimal focal point diameters and intensity distributions for varying material thicknesses, particularly in laser cutting, where a homogeneous temperature distribution and efficient molten material expulsion are necessary, but often result in non-uniform intensity profiles and limited Rayleigh length.
Innovation Solution
A beam forming lens system comprising an axicon array with microaxicons that create a flattened and/or annular intensity profile, featuring curved lateral surfaces and varied shapes to enhance homogeneity and increase Rayleigh length, allowing for adjustable ring thickness and peak intensity distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a standard focusing lens system is used, then the focal point diameter can be adjusted for different material thicknesses, but the intensity distribution becomes non-uniform and Rayleigh length is limited
Solution Approach 1:
The patent divides a single axicon into an array of multiple microaxicons. Each microaxicon creates a localized annular intensity profile, and the superposition of multiple such profiles results in a homogeneous annular intensity distribution over a larger area and extended Rayleigh length, resolving the contradiction between adaptability and intensity uniformity.
Solution Approach 2:
The patent transitions from a single-axis axicon to a two-dimensional array of microaxicons. This dimensional expansion allows the system to achieve both focal point diameter adjustment (adaptability) and homogeneous intensity distribution (stability) simultaneously by distributing the optical transformation across multiple elements in the array.
2Shape
If a single axicon is used to create an annular intensity profile, then the beam shape is transformed, but the intensity homogeneity and Rayleigh length are insufficient
Solution Approach 1:
By segmenting a single axicon into multiple microaxicons arranged in an array, the patent achieves superior intensity homogeneity. Each microaxicon contributes to the overall annular profile, and their collective superposition creates a more uniform and stable intensity distribution compared to a single axicon.
Solution Approach 2:
The patent combines the effects of multiple microaxicons to achieve an enhanced annular intensity profile. The merging of individual microaxicon outputs results in a homogeneous annular distribution with extended Rayleigh length, maintaining the desired shape while improving intensity stability.
3Productivity
If the focal point diameter is increased for thick material cutting, then the cutting capability improves, but the temperature distribution becomes less homogeneous
Solution Approach 1:
The microaxicon array segments the focal energy distribution into multiple localized annular regions that superpose to create a homogeneous overall profile. This allows the system to maintain uniform temperature distribution even when the overall focal point diameter is increased for thick material cutting applications.
Solution Approach 2:
The patent changes the optical parameters by using an array of microaxicons with specific geometric configurations. This parameter change enables the system to achieve both large focal point diameters (for thick material productivity) and homogeneous intensity distribution (for uniform temperature control) simultaneously.
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 a more homogeneous annular intensity profile with increased Rayleigh length, enabling efficient cutting of both thin and thick metal sheets with improved temperature distribution and molten material expulsion.
Implementation Method 1
A beam forming lens system refers to a lens system or multiple lens systems for respectively changing an intensity distribution or a shape of the laser beam. For example, beam forming lens systems can create flattened and/or annular intensity profiles in the focal plane. A beam forming lens system may comprise, for example, one or more diffractive or refractive optical elements.
Data Source
AI summary
The invention relates to a beam forming lens system for machining material using a laser beam, comprising a two-dimensional axicon array (10) featuring a plurality of microaxicons (11) for creating an annular laser beam intensity profile, the microaxicons (11) being provided with curved lateral surfaces (113). The invention also relates to an apparatus for machining material using a laser beam, comprising a beam forming lens system of said type and a focusing lens system (15) for focusing the laser beam onto a workpiece (18). The beam forming lens system is designed to create the annular laser beam intensity profile in a focal plane (F) of the focusing lens system (15).