Multi-viewpoint retinal projection displays with multilayer twisted liquid crystal lens array

Retinal projection displays (RPDs) relying on Holographic Optical Elements (HOEs) suffer from limited eye-box, inferior efficiency, and pronounced chromatic dispersion. To tackle these challenges, we propose a multi-viewpoint RPD architecture that achieves eye-box expansion and efficiency enhancement through a twisted nematic liquid crystal (TN-LC) lens array. The extended Jones matrix-based broadband wide-FOV optimization algorithm (EJM-BWOA) is developed to optimize lens layer thickness and twist angle, thereby realizing superior broadband and wide-angle polarization performance. Results verify that the multi-viewpoint structure enhances display performance under maximum horizontal eye rotation of ±30°, with the fabricated HOE lens reaching an efficiency of 47.38%. Furthermore, the optimized TN-LC lens achieves a polarization conversion efficiency (PCE) exceeding 90% across the visible spectral range (380-780 nm), while remaining functional at incident angles from 0° to 50°. Moreover, the proposed lens exhibits superior focusing capability at the RGB central wavelengths (450 nm, 532 nm, 630 nm). Collectively, this study establishes a novel, to the best of our knowledge, design paradigm for compact, high-performance near-eye displays, paving the way for further advancements in next-generation wearable display technologies.