Updated: Nov 2, 2022
Recent breakthroughs in virtual reality/augmented reality (VR/AR) technologies have not only attracted much attention from the scientific and industrial communities but have also piqued the interest of the general public. However, the widespread use of VR/AR devices is hindered by limitations associated with optical elements such as eyepieces, which are not only bulky but also suffer from poor imaging performance. A comfortable VR/AR display that meets the requirements of high quality near-eye imaging is needed. In this work, entitled "Meta-optics achieves RGB-achromatic focusing for virtual reality" in Science Advances, we demonstrate a meta-eyepiece that is capable of achromatic focusing of blue, green, and red light through the exploration of new design physics. Importantly, this dispersion-engineered metalens defies the conventional understanding of the physical constraints governing a Fresnel lens. The meta-eyepiece is made of complex TiO2 nanofins structures less than 1 micron thick and has a large aperture size of 2 mm. Its aberration-free RGB imaging quality, high numerical aperture, and lightweight profile makes this meta-eyepiece a strong contender to address the current challenges of VR/AR systems. We also developed a miniaturized full-color fiber scanning near-eye display inspired by bio-medical endoscopic imaging techniques through our collaboration with Prof. Ji-Xin Cheng’s group at Boston University. This display exhibits high resolution, high brightness, high dynamic range, and a wide color gamut. The combined system comprising meta-optics and a novel near-eye display may find future deployment in VR/AR headsets and other consumer electronics.