Spatial Frequency Filter Layout for Overlapped Laser Beam Components
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spatial frequency filter devices struggle to effectively filter undesired beam components that overlap with the main laser beam, as diffractive stops often either fail to filter these components or adversely affect the main beam.
Innovation Solution
A spatial frequency filter device with a neutral region and a deflecting region, where the deflecting region has a constant portion for reliable filtering of separated beam components and a variation portion for gradual filtering of overlapped components, allowing for precise deflection and removal of undesired beams without excessively cutting into the main beam.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a diffractive stop is used to filter undesired beam components, then separated beam components can be effectively filtered, but overlapped beam components cannot be filtered without adversely affecting the main beam
Solution Approach 1:
The filter device is segmented into two distinct functional regions: a first region with a diffractive structure for filtering separated beam components, and a second region with a gradual deflecting effect for handling overlapped components. This segmentation allows each region to specialize in handling specific types of beam components without interfering with the other's function.
Solution Approach 2:
Different regions of the filter device are assigned different optical properties: the first region has a strong diffractive effect with constant deflecting angle for separated components, while the second region has a gradual, position-dependent deflecting effect that increases toward the outer edge. This local differentiation enables tailored filtering strategies for different beam component types.
2Reliability
If a diffractive stop with constant deflecting effect is used, then separated beam components are effectively filtered, but overlapped beam components require excessive filtering that cuts into the main beam
Solution Approach 1:
The filter device applies different deflecting characteristics to different spatial regions: the first region maintains a constant deflecting angle suitable for separated components, while the second region implements a gradual increase in deflecting effect from inner to outer areas. This allows overlapped components to be filtered progressively without the abrupt cutoff that would otherwise interfere with the main beam.
Solution Approach 2:
By dividing the filter into two regions with distinct deflecting characteristics, the device can handle separated and overlapped components differently. The second region's gradual deflecting effect specifically addresses overlapped components without requiring the excessive filtering strength that would harm the main beam.
3Ease of manufacture
If aperture stops without diffractive region are used, then manufacturing is simpler, but virtual sources with undesired propagation directions occur affecting downstream optics
Solution Approach 1:
The filter device combines a diffractive first region with a second region that has gradual deflecting properties. This segmentation allows the inclusion of diffractive structures where they are most needed for preventing virtual sources, while the second region provides complementary filtering without the same harmful effects.
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 enables effective filtering of both separated and overlapped undesired beam components, ensuring minimal interference with the main beam, thereby improving the overall filtering capability of laser beams.
Implementation Method 1
an element which has an aperture and is arranged adjacent to the transmission body or is integrated in the transmission body, the element having a diffractive and/or refractive deflecting structure
Implementation Method 2
the element having a diffractive and/or refractive deflecting structure
Data Source
AI summary
A spatial frequency filter device is for use with a laser beam. The device includes: a neutral region, which is configured to transmit or reflect the laser beam; and a deflecting region, which radially adjoins the neutral region and is configured to deflect beam components of the laser beam from a beam axis of the laser beam. The deflecting region has a constant portion, in which a deflecting effect on the beam components of the laser beam for each location in the constant portion is configured to be independent of a distance of a location from the neutral region. the deflecting region has a variation portion, in which the deflecting effect on the beam components of the laser beam is configured to vary, dependent on a distance from the neutral region.