Liquid Crystal Polymer Waveplate for Curved AR Surfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional achromatic waveplates are complex to fabricate and costly, with challenges in attaching them to optical elements of high curvature due to difficulties in laminating flat films on curved surfaces, limiting their application in optical systems requiring broadband polarization control.
Innovation Solution
An optical waveplate configuration using a stack of multiple birefringent layers with twisted structures, where each layer has a spatially constant optic axis orientation, providing a substantially constant retardance over a design wavelength range, and can be fabricated using liquid crystal polymer coatings, allowing for easier integration on curved surfaces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional achromatic waveplates are used to achieve broadband polarization control, then polarization performance is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The waveplate is divided into multiple discrete birefringent layers with different optical axis orientations. Each layer is independently configured with specific twist angles and thicknesses, allowing modular assembly and simplified manufacturing while achieving broadband achromatic performance through the cumulative effect of segmented layers
Solution Approach 2:
The invention uses composite structures combining multiple birefringent materials with different optical properties. By stacking layers made of different liquid crystal polymers or birefringent materials with varying retardances and orientation characteristics, the system achieves broadband polarization control that cannot be obtained with single-material waveplates
2Ease of manufacture
If flat films are laminated to achieve waveplate structure, then manufacturing is simplified, but attachment to curved surfaces becomes difficult
Solution Approach 1:
The waveplate structure employs flexible thin film configurations that can conform to curved surfaces. The birefringent layers are designed as flexible films that maintain their optical properties while adapting to various surface geometries, enabling attachment to optical elements with high curvature without requiring rigid flat substrates
Solution Approach 2:
The invention explicitly designs the waveplate structure to accommodate curved and non-planar geometries. The birefringent layers are configured with orientations and thicknesses that maintain optical performance when applied to curved surfaces, transforming the conventional flat film approach into a curvature-adaptive structure
3Reliability
If multiple birefringent layers are stacked to achieve constant retardance, then broadband performance is improved, but manufacturing complexity increases
Solution Approach 1:
The invention systematically varies key parameters across the stacked layers, including twist angles, thicknesses, and optical axis orientations. By carefully controlling these parameter changes from layer to layer, the system achieves constant retardance across broadband wavelengths while providing a structured manufacturing approach that reduces complexity through parameter optimization
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 enables a simplified and cost-effective fabrication of broadband achromatic waveplates that can be easily integrated on curved surfaces, enhancing the optical system's performance and flexibility, particularly in augmented reality, virtual reality, and mixed reality applications.
Implementation Method 1
A first birefringent film including optically anisotropic molecules arranged to form a first twist structure. The optical waveplate also includes a second birefringent film stacked with the first birefringent film and including optically anisotropic molecules arranged to form a second twist structure.
Implementation Method 2
The optical waveplate is configured to provide a substantially constant retardance over a design wavelength range, and the substantially constant retardance over the design wavelength range is a quarter-wave retardance or a half-wave retardance
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An optical waveplate is provided. The optical waveplate includes a first birefringent film including optically anisotropic molecules arranged to form a first twist structure. The optical waveplate also includes a second birefringent film including optically anisotropic molecules arranged to form a second twist structure, the second birefringent film being stacked with the first birefringent film. The optically anisotropic molecules at a first portion of the first birefringent film adjacent an interface between the first birefringent film and the second birefringent film are configured with a first azimuthal angle. The optically anisotropic molecules at a second portion of the second birefringent film adjacent the interface are configured with a second azimuthal angle. The first azimuthal angle is substantially the same as the second azimuthal angle.