Athermal optical design of a freeform-waveguide AR display using a hybrid E48R/PMMA material system

The thermal stability of polymer-based optical systems poses a critical challenge for the commercialization of augmented reality (AR) displays, particularly those combining freeform optics and waveguides. This paper introduces a novel athermalized optical design that strategically employs a hybrid E48R and PMMA material system to mitigate performance degradation across a wide range of operational temperatures. The design achieves a wide 30° diagonal field of view (FOV) and a high resolution of 1024 × 768 within an ultra-compact 9 mm module. Beyond conventional performance metrics, this work provides a rigorous theoretical framework for passive athermalization in complex, multi-element AR systems. Performance is validated through polychromatic modulation transfer function (MTF) analysis, demonstrating stable values exceeding 0.4 at 30 lp/mm across a temperature range of 0°C to 40°C. A comparative analysis with contemporary designs highlights a significant improvement in thermal stability without compromising on FOV or form factor, presenting a manufacturable solution for robust consumer AR applications.