📄 Whitepapers¶
Welcome to the VirtualLab Fusion Whitepapers - a new addition to our documentation ecosystem. These technical documents explain the concepts, theory, and validated approaches behind our simulation capabilities.
While tutorials teach you how to accomplish specific tasks and use cases demonstrate what is possible, whitepapers go deeper into the why and how it works: the physics, the numerical methods, and the design principles that make our digital twins accurate and reliable.
The collection below is just the beginning - more whitepapers will be added over time.
📑 List of Whitepapers¶
| Title | Abstract |
|---|---|
| Simulation of Waveguides for AR Glasses and HUD | This white paper addresses the simulation of waveguides for AR glasses and head-up displays (HUDs). It covers four essential physical effects: propagation of coherent fields through lens systems (non-paraxial where required), polarization-dependent grating modeling via RCWA, diffraction at grating region boundaries (aperture effects), and temporal coherence from finite source bandwidth via OPL tracking. The paper presents simulation results comparing coherent and partially coherent illumination, with and without diffraction, validated against experimental MTF measurements. The underlying methods — field decomposition, LPIA, RCWA, aperture diffraction, and OPL tracking — are implemented in VirtualLab Fusion's Digital Twin Platform, where all components share a common electromagnetic field representation. The paper concludes with a set of essential questions for evaluating any simulation approach for AR/HUD waveguides. |
| PCA: The Foundation for Metalens Design | This white paper introduces the Periodic Cell Array (PCA) approximation as the foundation for metalens design. PCA restores local wavefront control on a flat surface by substituting each meta-atom's varying neighborhood with an idealized array of identical neighbors, capturing crosstalk while enabling independent meta-atom design. Within this substituted structure, Maxwell's equations are solved rigorously using RCWA. PCA enables efficient first-order analysis of functionality, aberrations, dispersion, and polarization dependency. Moreover, PCA enables the optical response of each meta-atom to be characterized independently of its neighbors — the essential foundation for building surrogate models that make large-scale metalenses tractable. Second-order analysis tools (efficiency, higher orders, scattering) become relevant only after PCA shows promise. PCA for design is the only way to enable local design; second-order tools further evaluate performance. |
| Designing and Analyzing the Phase Response of Metasurfaces | This white paper establishes a rigorous framework for defining, extracting, and evaluating the phase response of metasurface meta-atoms, introducing the local common phase \(\Psi = \arg(J_x^{\text{out}} + J_y^{\text{out}})\) as the design-relevant quantity, a quality criterion \(\sigma^2\) for input polarization selection, and optimal basis analysis \((\mathbf{J}_1, \mathbf{J}_2)\) for pillars (linear) and nanofins (circular). |
| Surrogate Modeling: Enabling Practical Metalens Design and Simulation | This white paper describes the surrogate model for meta-atom electromagnetic response, which replaces on-the-fly RCWA with precomputed Jones matrices \(\mathbf{M}(\lambda, \theta_x, \theta_y, \mathbf{p})\), enabling fast forward queries (amplitudes, common phase \(\Psi\), variance \(\sigma^2\)), optimal basis analysis, design-related linear phase ramp scans, step size and quantization error analysis, and inverse queries for metasurface design. |
📖 What to Expect from a Whitepaper¶
Whitepapers in this collection are technical documents that:
- Explain the physics behind an application area or simulation method
- Describe validated approaches - what works, why, and under which assumptions
- Provide context for the decisions made in our use cases and solution guides
- Reference the underlying methods as implemented in VirtualLab Fusion
💬 Feedback¶
Is there a topic you would like to see covered in a future whitepaper?
📧 Email: support@lighttrans.com
Happy reading!