Summary:
UCLA researchers from the Department of Electrical & Computer Engineering have developed a curved grating element that enables higher efficiency and resolution in augmented (AR) and virtual reality (VR) devices.
Background:
Grating structures are a fundamental component of AR and VR devices and are necessary for controlling the diffraction of light waves from the source to the user’s eyes. Light can diffract either in-plane (i.e., along the plane of the grating structure) or off-plane (i.e., perpendicular to the grating structure). While 1D in-plane grating structures have a high diffraction efficiency, 2D off-plane grating structures have a greater capability to display complex images. However, existing 2D grating structures suffer from reduced diffraction efficiency, which limits their use in advanced applications. The size and cost of current technologies further limits their widespread use for educational and gaming purposes. Recent advances in optical devices provide an opportunity to develop high performing grating structures with improved efficiency and reduced size. There remains an unmet need for an affordable high-resolution grating element with a high diffraction efficiency.
Innovation:
UCLA researchers in the Department of Electrical and Computer Engineering have developed curved holographic aligned nonlinear grafting elements (CHANGE) for use in high resolution augmented and virtual reality. The 1-dimensional shape of the optical element allows for high efficiency diffraction, while the curved design of the device permits high resolution, off-plane diffraction. Due to the modular design of CHANGE, the device can be customized to fit the properties of the light source, ensuring that various wavelengths are diffracted with the desired resolution and in the correct direction. These advances in the design of grating elements are critical for the development of next generation, high resolution and high-performance AR and VR devices.
Potential Applications:
• AR/VR devices
• Holography
• Medical imaging
• Color balance correction
Advantages:
• Diffraction efficiency comparable to 1D grating structures
• Capable of displaying complex images
• Customizability
• Simplified design in cascaded adaption
Development to Date:
Prototype successfully demonstrated in 2020.
Related Papers:
Metasurface wavefront control for high-performance user-natural augmented reality waveguide glasses (https://doi.org/10.1038/s41598-022-09680-1)
Reference:
UCLA Case No. 2022-320
Lead Inventor:
Chee Wei Wong