What Exactly Is a Metalens?
Metalens is a lens with the ability to focus and capture light signals beyond the diffraction limit. The basic principle is to change the curvature of the lens to achieve the focusing or dispersion of light, via the use of man-made sub-wavelength unit structure in the traditional medium for wavefront modulation of optical devices. It is a two-dimensional plane lens structure and is made of a super-surface (by the multilayer metal mask, with a sub-wavelength thickness of the plane of the two-dimensional (2D)) metamaterial) optical elements that focus light. With the advantages of thinner size, lighter weight, lower cost, better imaging, and easier integration, metalenses offer a potential solution for compact integrated optical systems. Moreover, the properties of light such as polarization, phase and amplitude can be regulated by adjusting the shape, rotation direction, height and other parameters of the structure. Conventional lenses work on the basis of the law of refraction, where they focus or scatter light through changes in curvature. However, this approach has limitations in some cases, such as for focusing to very small points or when dealing with light of a specific frequency. metalenses employ a different principle, in that they achieve precise control of light through the design of micro-nano-structures. These micro-nano-structures can be metals, dielectric materials or combinations thereof, and their periodicity and geometry determine the performance of the metalens, which operates based on controlling the phase and amplitude, rather than controlling the light through refraction alone. It is characterized by its ability to compensate for the limitation of ordinary lenses by the diffraction limit, focusing the light into fine points. Metalens is a new technological breakthrough for the field of optics, compared with traditional optical lenses metalens uses nanostructures by replacing traditional lenses, which are currently large and costly in optics, with simple, flat surfaces. This disruptive technology brings new hope for solving the problems of traditional lenses, and will usher in a change in the optics industry. Metalenses have a wide range of applications, can be used in nano-optics, optical data storage, image processing, terahertz optics and other fields, and is a hot spot in the field of optical science research in the future.
For more information on metallens products, please visit Flat & Meta Lenses.