Reviewed by Lexie CornerMar 6 2025
An international team of scientists from the University of Tokyo developed augmented reality glasses capable of receiving images from a projector. This technology addresses some of the current limitations of AR glasses, such as bulk and weight. The team plans to present their study at the IEEE VR conference in March 2025 in Saint-Malo, France.
Researchers developed this system for AR glasses based on the “beaming display” approach. The system receives projected images from a dedicated projector placed in the environment and delivers AR visuals to the user. Image Credit: Yuta Itoh, Tomoya Nakamura, Yuichi Hiroi, Kaan Akşit
Augmented reality (AR) technology, which overlays digital data on the real world through a device’s display, has grown in popularity. It is used in gaming apps like Pokémon Go and industries such as education, manufacturing, retail, and healthcare. However, the adoption of wearable AR devices has been slow due to their weight, electronics, and battery requirements.
AR glasses can change a user's physical surroundings by incorporating virtual components. While hardware technology has improved, AR glasses remain bulky and lack the necessary processing power, battery life, and brightness for optimal performance.
A research team from the University of Tokyo and their partners developed AR glasses that receive images from projectors, bypassing these limitations.
This research aims to develop a thin and lightweight optical system for AR glasses using the ‘beaming display’ approach. This method enables AR glasses to receive projected images from the environment, eliminating the need for onboard power sources and reducing weight while maintaining high-quality visuals.
Yuta Itoh, Project Associate Professor, Interfaculty Initiative in Information Studies, University of Tokyo
The practicality of light-receiving AR glasses was previously limited by the angle at which they could receive light. In earlier designs, cameras could only display images on AR glasses when they were angled within 5 º of the light source.
The research team addressed this issue by incorporating patterned grooves, or diffractive waveguides, to control the direction of light in their AR glasses.
By adopting diffractive optical waveguides, our beaming display system significantly expands the head orientation capacity from five degrees to approximately 20-30 º. This advancement enhances the usability of beaming AR glasses, allowing users to freely move their heads while maintaining a stable AR experience.
Yuta Itoh, Project Associate Professor, Interfaculty Initiative in Information Studies, University of Tokyo
The AR glasses' light-receiving mechanism consists of two parts: the screen and waveguide optics. Light is first received by a diffuser, which evenly directs it toward the lens. The image light is then guided by a diffractive waveguide toward gratings on the eye surface of the glasses. These gratings capture the image light and direct it toward the user's eyes to create an AR image.
To test their technology, the researchers developed a prototype that used a laser-scanning projector. This projector, angled between zero and 40 º, projected a 7-mm image onto the glasses from a distance of 1.5 meters.
The team’s AR glasses can now receive projected light with acceptable image quality from angles between 5 º and 20-30 º, thanks to the addition of gratings that direct light both inside and outside the system as waveguides.
While this new light-receiving technology improves the usefulness of AR glasses, the team acknowledges that further testing and improvements are needed.
Future research will focus on improving the wearability and integrating head-tracking functionalities to further enhance the practicality of next-generation beaming displays.
Yuta Itoh, Project Associate Professor, Interfaculty Initiative in Information Studies, University of Tokyo
To improve the usefulness of light-receiving AR glasses in three-dimensional environments, future testing setups should ideally track the position of the glasses and use steerable projectors to direct images to them appropriately. The image quality could also be enhanced by using light sources with higher resolution.
The team also aims to address several issues in their current design, including two-dimensional images, monochromatic images, ghost images, a small field of view, and flat waveguides that cannot accommodate prescription lenses.