Angular uniformity improvement of diffractive waveguide display based on region geometry optimization.

Area of Science:

• Optics and Photonics
• Nanotechnology
• Display Technology

Background:

• Augmented reality (AR) near-eye displays rely on nanostructure fabrication for progress.
• Diffractive waveguide AR displays need improved angular uniformity for exit pupil expansion.
• Current methods face challenges in achieving consistent light distribution across the exit pupil.

Purpose of the Study:

• To propose and verify a novel method for enhancing angular uniformity in diffractive waveguide AR displays.
• To optimize the energy distribution of light interacting with gratings within the waveguide.
• To improve the overall optical efficiency and uniformity of AR near-eye displays.

Main Methods:

• Region geometry optimization incorporating light-grating interaction number.
• Rigorous coupled wave analysis (RCWA) and ray tracing for light distribution analysis.
• Multi-objective genetic algorithm for optimizing grating parameters.

Main Results:

• The proposed method significantly increased overall optical efficiency from 0.9% to 3.1%.
• Angular uniformity at the center exit pupil position improved from 66% to 80%.
• A functional model demonstrated the feasibility of the optimization technique.

Conclusions:

• Region geometry optimization is an effective strategy for improving angular uniformity in diffractive waveguide AR displays.
• The developed method enhances both optical efficiency and uniformity, crucial for AR display quality.
• This work contributes to the advancement of high-performance AR near-eye display technologies.