CEA-Leti, a French research institute for electronics and information technologies, has developed a novel retinal-projection concept for augmented reality (AR) uses based on a combination of integrated optics and holography.

The lens-free optical system uses disruptive technologies to overcome the limitations of existing AR glasses such as limited field-of-view and bulky optical systems. In typical AR glasses, images are transmitted close to the eyes by a microdisplay that includes an optical system and an optical combiner. The microdisplays create a small near-to-eye image, which is transformed by the optical system, enabling the user to see it despite the short focusing distance. The combiner superimposes the digital image to the viewer’s vision of the real environment.

CEA-Leti’s innovation is a transparent retinal-projection device that projects various light waves to the eyes from a glass surface. Images are formed in the retina by the interference of light waves, which eliminates the need for optical systems or combiners. The light propagating in the air doesn’t form an image until it interferes precisely in the retina. integration of the device and its use of a holographic layer also allow creation of compact AR glasses with a larger field-of-view than existing systems, while the transparent retinal projection device allows ambient light to pass through the device for enhanced AR applications.

The novel approach will require further development before it reaches the commercialization stage.