Diffractive Optical Element Birefringence Dispersion Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current diffractive optical elements face challenges in achieving high diffraction efficiency and wide bandwidth while maintaining a compact size, particularly in optical devices where size and thickness are critical, and existing solutions do not effectively manage birefringence dispersion across various wavelengths.
Innovation Solution
A diffractive optical element is designed with a diffraction layer using an anisotropic material that satisfies specific birefringence relationships across different wavelengths, featuring a grating pitch and optical axes aligned in the in-plane direction, which ensures high diffraction efficiency and a wide bandwidth by optimizing birefringence dispersion and diffraction angles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional diffractive optical elements are used, then device size can be reduced, but diffraction efficiency and bandwidth are insufficient
Solution Approach 1:
The patent changes the material parameter by using anisotropic materials with specific birefringence characteristics that satisfy particular relationships across different wavelengths. This parameter change enables simultaneous achievement of high diffraction efficiency (70-100%) and wide bandwidth by optimizing how the material interacts with different wavelength components of light
Solution Approach 2:
The patent employs composite material structures combining anisotropic materials with specific optical properties. The diffraction layer uses materials exhibiting controlled birefringence dispersion, creating a composite optical system that achieves both high efficiency and broad spectral coverage through the synergistic interaction of material properties
2Loss of energy
If diffractive optical elements are designed for high diffraction efficiency, then energy loss is reduced, but bandwidth is limited
Solution Approach 1:
By modifying the material's birefringence parameter to satisfy specific relationships across wavelengths, the patent achieves high diffraction efficiency with reduced optical path length requirements, thereby expanding bandwidth without sacrificing efficiency
3Adaptability or versatility
If broadband performance is achieved, then adaptability is improved, but diffraction efficiency decreases
Solution Approach 1:
The patent inverts the conventional approach by first establishing specific birefringence relationships as design parameters, which then naturally produce both wide bandwidth and high diffraction efficiency simultaneously, rather than sacrificing efficiency for bandwidth
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 diffraction efficiencies of 70% to 100% across various wavelengths with minimal variation, providing a wide bandwidth and enabling applications in compact optical devices like lenses and prisms with improved performance.
Implementation Method 1
the diffraction layer includes an anisotropic material that satisfies one of Relationship Equations 1A to 3A... Δn1 (450 nm) is birefringence of an anisotropic material at a wavelength of 450 nanometers (nm)... the anisotropic material has a birefringence dispersion satisfying Relationship Equations 4A and 5A
Implementation Method 2
A diffractive optical element includes a diffraction layer including a plurality of optical axes along an in-plane direction... the optical axis of the diffraction layer may be configured to change periodically along the in-plane direction... the diffraction layer may include at least one grating pitch
Data Source
AI summary
A diffractive optical element including a diffraction layer including a plurality of optical axes along an in-plane direction, wherein the diffraction layer includes an anisotropic material that satisfies one of Relationship Equations 1A to 3AΔn1(450 nm)<Δn1(550 nm)≤Δn1(650 nm) Relationship Equation 1AΔn1(450 nm)≤Δn1(550 nm)<Δn1(650 nm) Relationship Equation 2AΔn1(450 nm)=Δn1(550 nm)=Δn1(650 nm) Relationship Equation 3Awherein, in Relationship Equations 1A to 3A,Δn1 (450 nm) is a birefringence of the anisotropic material at a wavelength of 450 nanometers,Δn1 (550 nm) is a birefringence of the anisotropic material at a wavelength of 550 nanometers, andΔn1 (650 nm) is a birefringence of the anisotropic material at a wavelength of 650 nanometers.