Design and fabrication of a compact coaxial catadioptric augmented reality near-eye display enabled by genetic algorithm

The way we interact with the world is constantly evolving thanks to developments in virtual reality (VR) and augmented reality (AR) technologies. AR has been extensively employed in a variety of fields and is one of the metaverse's key interfaces. It has always been difficult to develop and process an optical see-through (OST) AR with a wide field of view (FOV) that is also compact, lightweight, and low in stray light. In this study, we develop and build a high-brightness microdisplay-based polarized catadioptric AR near-eye display (NED) system with a birdbath (BB) structure. We suggest a unique optical design that uses a Mangin lens as a reflector and incorporates polarization elements into this system to address the issue of the classic BB AR NED system's inefficient use of energy. The optical and structural restrictions used in the design process are expressed mathematically. A solution for solving the initial structure using a genetic optimization algorithm is proposed based on this optical morphology. Using the resolved initial structure, the optimization design and image quality analysis procedure are detailed. The completed device has a 0.71-inch microdisplay with a diagonal FOV of 50°, an exit pupil diameter (EPD) of 8 × 6 mm, an eye relief (ERF) of 15.7 mm, and a maximum total length (TTL) of 15.4 mm. The system's paths and modes for generating stray light are examined, and the related techniques for reducing and eliminating stray light are provided. The system's prototype was finally processed successfully, confirming its great performance and adaptability.