MEMS-Driven Dynamic Pupil Expansion for High-Performance Retinal Projection Near-Eye Displays

The designed optical architecture exhibits high imaging performance, achieving a modulation transfer function (MTF) exceeding 0.3 at 66.7 lp/mm at the central viewpoint, with system distortion maintained below 3%. Notably, the MEMS scanning mirror enables lateral shifting of the exit pupil, forming a large eye-box of 10 mm × 10 mm. This approach breaks the inherent coupling between eye-box expansion and optical efficiency found in static methods, thus achieving high light efficiency without compromising image quality due to aberrations.

Experimental results validate the system’s performance under accommodation distances ranging from 30 to 120 cm, confirming excellent image quality and luminance uniformity across the eye-box. This work demonstrates the feasibility of MEMS-enabled pupil expansion and supports future development of compact, high-performance retinal projection displays.