WiMi Hologram Cloud Inc., a leading global Hologram Augmented Reality (“AR”) Technology provider, today announced that a metasurface eyepiece for augmented reality has been developed, which is based on metasurfaces composed of artificially fabricated subwavelength structures. The metasurface eyepiece employs a special optical design and engineered anisotropic optical response to achieve an ultra-wide field of view(FOV), full-color imaging, and high-resolution near-eye display.
At the heart of the WiMi’s metalens are see-through metalens with a high numerical aperture(NA), a large area and broadband characteristics. Its anisotropic optical response allows it to perform two different optical functions simultaneously. First, it can image virtual information, acting as an imaging lens for virtual information. Second, it can transmit light, serving as a transparent glass for viewing a real-world scene. This design allows the transparent metalens to be placed directly in front of the eye without the need for additional optics, resulting in a wider FOV.
Fabrication of metalens is done using nanoimprinting technology, which is capable of fabricating large-area metalens with sub-wavelength structures. First, a mould or template with the desired structure is prepared. Then, the mould or template is contacted with a transparent substrate and the nanoscale structure is transferred by applying pressure and temperature. Through this nanoimprinting process, the subwavelength structure of the metalens is successfully replicated onto the transparent substrate, resulting in the formation of the metalens.
A metasurface eyepiece developed by WiMi for augmented reality underwent a series of optical performance tests to ensure that it has high transmittance, modulation efficiency and dispersion characteristics. Transmittance tests evaluated the transmittance of the metalens in different wavelength ranges to ensure high transmittance over the entire visible light range. The modulation efficiency test evaluates the modulation capability of the metalens in transmitting optical signals to ensure that it can accurately image virtual information. The dispersion characteristics of the metalens are also evaluated to ensure color accuracy and imaging quality over a broadband range. In experiments in a prototype display system, WiMi’s researchers realized a transparent near-eye display with a wide FOV(90°). By increasing the diameter of the metalens, the FOV could be further extended to over 120°. This was achieved by adjusting the size and shape of the metalens and optimizing the optical design. The design and manufacturing process of the metalens is precisely optimized and tuned to ensure the best possible FOV and imaging performance.
The technology has the following differences and advantages over the current technology and it can address some of the problems and defects of the current technology:
Ultra-wide FOV: The metasurface eyepiece achieves an ultra-wide FOV relative to traditional augmented reality glasses. Through the optimized design and use of see-through metalens with engineered anisotropic optical response, the FOV can reach over 90° and can even be extended to over 120° by increasing the diameter of the metalens. This greatly enhances the user’s FOV for a more immersive augmented reality experience.
High resolution and full-color imaging: traditional AR technology has some limitations in terms of resolution and color reproduction. The metasurface eyepiece achieves high resolution and full color imaging by using high-performance see-through metalens. When viewing virtual information or real-world scenes through the lens, users can get clearer and more realistic image quality and color rendering.
Compact design expanded eye box: Traditional augmented reality glasses typically require the use of larger optics, resulting in a larger device and potentially restricting the space for eye movement. In contrast, metasurface eyepieces utilize the anisotropic optical response of the metalens to position it directly in front of the eye, eliminating the need for additional optical elements. This allows the metasurface eyepiece to have a more compact design and a large enough eye box to allow the user to view images freely and comfortably.
Mass production advantages and wearability: The technology utilizes nanoimprinting to fabricate metalens, enabling mass production of transparent metalens with large areas and high numerical apertures. The nanoimprinting technique is more scalable and cost-effective than traditional methods of manufacturing optical components. This allows the metasurface goggles to be better adapted to commercialization needs and improve the productivity and usability of wearable devices.
Mobility and portability: Thanks to the compact design and lightweight metalens, the metasurface eyepiece offers better mobility and portability. Compared to traditional bulky optics, it is more suitable for mobility and use in different scenarios, providing users with a more flexible augmented reality experience.
A metasurface eyepieces developed by WiMi has successfully solved some of the problems and shortcomings of traditional augmented reality technology, such as narrow FOV, resolution limitation, bulky size, etc., through the advantages mentioned above, and has improved the quality and comfort of the AR experience. It provides a more advanced solution for augmented reality and other applications in other fields. By breaking through the limitations of traditional optics, metalens technology brings a breakthrough to the usability and mobility of AR glasses. It provides users with a wider, immersive augmented reality experience and brings new development opportunities with a wide range of potential applications in fields such as wearable devices, optical displays, computer vision, wearable electronics, bio-imaging, medical devices and optical microscopy.
WiMi will continue to conduct research and development in the area of metasurface technology and optical display systems to further optimize and improve the technology. They will work to improve the performance and manufacturing efficiency of the metalens and drive the widespread adoption of the technology in commercialized applications. This innovation will drive the industry forward and provide users with a more immersive and high-quality augmented reality experience.