Compact dual-focal augmented reality head-up display using a single picture generation unit with polarization...

Area of Science:

• Optics and Photonics
• Automotive Technology
• Human-Computer Interaction

Background:

• Augmented reality head-up displays (AR-HUDs) offer multiple focal planes and wider fields of view (FOV).
• Existing dual-focal AR-HUDs using two picture generation units (PGUs) suffer from increased size, cost, and reduced reliability.
• Previous attempts to halve PGU resolution for dual-focal displays compromised image quality.

Purpose of the Study:

• To propose a compact and high-resolution dual-focal AR-HUD system.
• To overcome the resolution limitations of previous dual-focal AR-HUD designs.
• To achieve high image quality and implement distortion correction for practical AR-HUD applications.

Main Methods:

• Developed a dual-focal AR-HUD architecture utilizing a single PGU and a freeform mirror.
• Implemented polarization-multiplexing to allow each virtual image to use the full PGU resolution.
• Performed optical design optimization and developed a distortion correction method using an inverse optical path.

Main Results:

• Achieved high image quality (excluding distortion) in a large eyebox (130 x 60 mm) for both far (10m) and near (2.5m) virtual images.
• Demonstrated a compact system volume of 9.5L, comparable to single-focal HUDs.
• Successfully built and experimentally verified a prototype AR-HUD demonstrating polarization-multiplexing and expected image quality.

Conclusions:

• The proposed single-PGU, freeform mirror AR-HUD with polarization-multiplexing effectively addresses the limitations of previous dual-focal systems.
• The integrated distortion correction method ensures practical image quality for AR-HUD applications.
• The compact and high-performance design offers a viable solution for next-generation AR-HUDs.