Reviewed by Danielle Ellis, B.Sc.Sep 26 2024
Researchers describe in ACS Photonics how to combine two optical technologies into a single, high-resolution augmented reality display, making the technology easier to integrate into everyday personal devices. The researchers improved image quality in a prototype pair of glasses by using a computer algorithm to eliminate distortions.
A new, simpler AR display incorporated into eyeglasses takes an original image (top) and produces a projected image (middle) that is further enhanced by a computer algorithm (bottom). Image Credit: Adapted from ACS Photonics 2024.
Digital photos are overlaid onto real-world views using augmented reality (AR). AR, however, has the potential to change both surgery and self-driving cars. It is not just a new way to play video games.
AR systems need portable optical components similar to those found in bulky goggles and head-up displays in cars. However, reducing the size of the standard four-lens AR system to the size of spectacles or less usually decreases the quality of the computer-generated image and reduces the field of view. Youguang Ma and associates may have discovered a way to simplify the technology.
To create a small, single-lens hybrid AR design, the team fused two optical technologies, a metasurface and a refractive lens, with a microLED screen that held arrays of tiny green LEDs for image projection.
The display is made of a lightweight, ultrathin silicon nitride film that has been pattern-etched. The design concentrates and shapes the light coming from the green microLEDs. Next, a black-and-green picture develops on a synthetic polymer refractive lens, which sharpens and lessens light aberrations to refine the image further. The system projects the finished picture, which is then superimposed on a screen or object. Ma and colleagues employed computer algorithms to detect small flaws in the optical system and fix them before light leaves the microLED, thereby improving the resolution of the projected image.
The researchers incorporated the hybrid AR display into a pair of eyeglasses, and the team used computer image enhancement to evaluate the prototype's functionality. The one-lens hybrid system produced projected images with less than 2% distortion over a 30° field of view, which is comparable to the image quality of the four-lens commercial AR platforms available today.
Subsequently, the researchers verified that the red panda image they had reprojected using the computer preprocessing algorithm was now better.
The reprojected red panda showed a 4% improvement over the original image in terms of structural similarity, coming in at 74.3%. According to the researchers, the platform has the potential to go from green to full color with further development, opening the door for a new wave of widely available AR glasses.
The National Natural Science Foundation of China, the Natural Science Foundation of Zhejiang Province, and the National Key Research and Development Program of China funded the research.
Journal Reference:
Chen, A., et al. (2024) Hybrid Meta-Optics Enabled Compact Augmented Reality Display with Computational Image Reinforcement. ACS Photonics. doi.org/10.1021/acsphotonics.4c00989.