In the consumer electronic, industrial, medical, and automotive marketplace there is demand for light weight imaging systems with optical lenses that have a wide field of view (WFOV) and can also operate over a large bandwidth. Conventionally, refractive lenses have been used to control light transmission, and new technologies have enabled thinner and lighter refractive lenses. However, achieving adequate phase change becomes challenging due to the limited refractive indices of natural materials. Diffractive lenses offer the ability to correct aberrations that are difficult to manage with refractive lenses, however, they can have considerable dispersion, shadowing effects, and integration difficulties. A metalens can enable ultra-thin devices with a high degree of customization and functionality. One approach involving the stacking of metalenses can achieve the WFOV, but increases complexity and negates the primary benefit of reduced thickness and weight.
Recent work addresses these challenges by using a single layer imaging metalens that utilizes an advanced quadratic phase profile specifically engineered to achieve a WFOV. This lens demonstrates of WFOV of 176°. Additionally, it is optimized for immediate compatibility with non-polarized light and integrates with conventional color filters commonly used in most camera systems.
The novel work was reported by Azhar Javed Satti, Eunji Lee, Isma Javed, Kyungtae Kim, Kim Joohoon, Muhammad Ashar Naveed, Muhammad Zubair, Qammer H. Abbasi, CEng, FEAI, FIET, FRSE, Dr. Muhammad Qasim Mehmood, and Junsuk Rho in a collaborative effort from Information Technology University, Pohang University of Science and Technology, University of Nebraska-Lincoln, University of Leicester, University of Glasgow, POSCO-POSTECH-RIST Convergence Research Center for Flat Optics and Metaphotonics, and National Institute of Nanomaterials Technology (NINT) (Korea).
The work was performed in part using an STS-Elionix ELS-BODEN electron beam lithography system at the Pohang University of Science and Technology.
For more information see https://lnkd.in/eZRwfSKV.
Image: (a) Fabrication process flow of metalens. (b) Photograph of mechanically incorporated metalens. (b inset) Scanning electron microscopy (SEM) result of the metalens (Scale bar: 1 μm). (Image use is made available under the terms of the Creative Commons BY-NC 4.0 license.)