Beam Splitter Spatial Separation for UV Radiation Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing devices for generating electromagnetic radiation in the ultraviolet spectral range face high absorption and scattering losses, and coating degradation in dichroics, leading to premature device failure.
Innovation Solution
Incorporating a beam splitter element that causes the first and second radiation to propagate in different spatial directions, allowing for effective spatial separation and coupling-out of the second radiation from the optical resonator, thereby avoiding the limitations of conventional dichroics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a dichroic is used to couple out the second radiation from the optical resonator, then the device structure is simple, but absorption and scattering losses become very high and coating degradation occurs in the ultraviolet spectral range
Solution Approach 1:
The patent extracts the harmful function of the dichroic coating by removing it entirely from the system. Instead of using a dichroic mirror to separate wavelengths, the invention uses a beam splitter element combined with spatial separation through the non-linear crystal's walk-off angle, thereby eliminating the source of absorption and scattering losses in the ultraviolet range.
Solution Approach 2:
The patent introduces a beam splitter element as an intermediary component that replaces the dichroic. This beam splitter, combined with the spatial separation effect in the non-linear crystal, provides a new mechanism for wavelength separation that avoids the harmful interactions between ultraviolet radiation and dichroic coatings.
2Device complexity
If a dichroic is used to couple out the second radiation from the optical resonator, then the device structure is simple, but coating degradation occurs leading to premature device failure
Solution Approach 1:
The patent removes the dichroic coating from the system entirely, eliminating the reliability issue of coating degradation. The wavelength separation function is achieved through the beam splitter element and the natural spatial separation in the non-linear crystal, which do not suffer from ultraviolet-induced coating degradation.
Solution Approach 2:
The patent replaces the fragile, degradation-prone dichroic coating with more robust optical components (beam splitter element and non-linear crystal) that have superior long-term stability in the ultraviolet spectral range, thereby improving device reliability and lifetime.
3Productivity
If the non-linear crystal thickness is increased to improve frequency conversion, then the conversion efficiency increases, but the beam displacement at the crystal exit remains insufficient for effective coupling-out
Solution Approach 1:
The patent utilizes the spatial separation that occurs in the lateral dimension within the non-linear crystal due to the walk-off angle. By combining this lateral separation with the beam splitter element, the system achieves sufficient beam displacement for effective coupling-out while maintaining the necessary crystal thickness for high conversion efficiency.
Solution Approach 2:
The beam splitter element acts as an intermediary that amplifies and utilizes the small beam displacement generated by the non-linear crystal. It redirects the spatially separated beams to achieve effective coupling-out of the second radiation, solving the problem of insufficient displacement.
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 enables efficient generation of wavelength-converted radiation in the ultraviolet range with reduced losses and improved long-term resistance, ensuring the device's longevity and performance.
Implementation Method 1
The non-linear crystal of the frequency multiplier features a non-linear susceptibility. This feature is exploited for generating a second radiation from the first radiation at a second or higher harmonic wavelength.
Implementation Method 2
Within the non-linear crystal, there is an angle developing between the propagation directions of the first radiation and the second radiation. This angle is also designated as 'walk-off' angle. Hence, a spatial separation of the two beams of the first and the second radiation is thus already created in the interior of the non-linear crystal.
Implementation Method 3
The optical resonator is resonant at the fundamental wavelength, thus causing an excessive increase of the radiation intensity in the resonator.
Data Source
AI summary
A device for generating electromagnetic radiation includes a light source (1) generating a first radiation (7) at a fundamental wavelength, an optical resonator (2) in which the first radiation (7) circulates, and a frequency multiplier (8) located in the optical resonator (2) which converts the first radiation (7) at least partly into a second radiation (9) at a second or higher harmonic wavelength. The frequency multiplier (8) includes at least one non-linear crystal (10). At least one beam splitter element (12) passed through by the first radiation (7) and the second radiation (9) is coupled to the non-linear crystal (10), wherein the first radiation (7) and the second radiation (9) leave the beam splitter element (12) each in a different spatial direction.