Solutions | Optical Systems
This page covers near-eye displays for AR built on diffractive waveguides: seeing through to the real world while replicating the pupil by diffraction to deliver an image to the eye. Efficiency, eye box and color uniformity are all set by diffraction physics that geometric ray tracing alone cannot compute.
Design challenges
In a waveguide architecture the in-coupler, the pupil expander and the out-coupler are all sub-wavelength gratings. Diffraction efficiency across a wide range of angles and wavelengths directly determines the eye box and the color uniformity. Unless the results of rigorous electromagnetic analysis can be carried into a whole-system ray trace, the components can be optimal and the device still not work. The final verdict comes from how it looks to a person at real-world luminance.
Design and simulation workflow
Select the waveguide architecture and design the field of view, distortion and imaging performance.
Place the in-coupling, pupil expansion and out-coupling gratings so the light path works.
Sweep the angle of incidence and wavelength to obtain bidirectional diffraction efficiency.
Build the response obtained into the ray trace as a sub-wavelength model.
Evaluate eye box, efficiency, color uniformity and the luminance distribution at the viewing position.
Evaluate contrast and readability, including adaptation to ambient luminance.
The stages differ by project. Immersive (VR) optics without a waveguide are arranged differently, so please talk to us separately about those.
Related analysis technologies
The principles and scope of each method are explained on the Analysis Technologies pages.
Related products
The capabilities and coverage of each product are described on its own product page.
Handles grating diffraction. RCWA and FDTD give bidirectional diffraction efficiency across a sweep of angle and wavelength.
Stage / 03
Handles design of the projection and imaging optics. Sequential ray tracing sets the field of view, distortion and imaging performance.
Stage / 01-02
Handles verification of whole-system light distribution and appearance. Non-sequential ray tracing and human vision simulation evaluate the eye box and readability.
Stage / 04-06
Related technical information
Technical Information
How to link Lumerical and Zemax
Tell us where the design stands, how far architecture selection has progressed, your field of view and eye box targets, and any existing design data, and we will propose a way forward.