Meta-Lens in the Sky

摘要

Meta-lenses are advanced optical devices composed of artificial nano-antenna arrays. Its flat, light-weight, ultra-thin, compact, customizable, and easy-to-integrate advantages enable widely potential usages in new demands. We demonstrate a GaN-based polarization-independent meta-lens-based camera on a drone. The diameter of the meta-lens is 2.6 mm, and the measured focal length is 5.03 mm under the 532 nm light incident. An array of the 750 nm height cylindrical nano-antennas with various sizes of the meta-lens provides the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\pi $ </tex-math></inline-formula> phase modulation of the focusing phase distribution. The meta-lens is integrated with an image sensor and mounted on the drone to realize the aerial photography and landing assistance. By taking images of the specific pattern on the ground at different heights through the meta-lens, the flying height of the drone can be detected for landing and flying. We trust meta-lens-camera can reduce the weight burden for prolonging flight time. We believe the meta-lens-based optical devices for imaging and sensing is an important key for micro/nano-robots, micro air vehicles, and intelligent sensing devices in the future.