NIL Technology has core know-how on optical design of metalenses with a full process chain under one roof.
In 2019, World Economic Forum names metalenses as one of top 10 emerging technologies. Not without reason. They have powerful capabilities beyond traditional optical lenses with flat surfaces, reduced thickness, and improved quality across all optical component use cases.
NIL Technology has design, prototyping and manufacturing capabilities of metalenses. We can characterize metasurfaces for visible and IR applications up to ~2000 nm. Other beam shaping functions, such as diffusers and fan-out gratings can also be realized with metasurfaces.
Dark field optical microscopy demonstrating lensing effect for a large range of wavelengths. The cover image shows a fresnel metalens, demonstrating pillars down to sub 100 nm diameters with perfect vertical sidewall
What are metalenses?
Metalenses are optical components that use metasurfaces to focus light. They can be used in optical applications that take advantage of the flat surface and reduced thickness, compared to classic, curved refractive lenses that are mainly used in optical devices today. Metalenses allow further miniaturization in sensors and different imaging devices.
Meta-atoms and metasurfaces
Metalenses utilize the phase change that can be induced locally on a light wave by a small nano-sized feature. Nanostructures, often called meta-atoms, are often pillars of various cross sections and in many cases cylindrical. The induced phase change depends on the size and geometry of the meta-atoms. By properly selecting and distributing meta-atoms over a surface, the wavefront of an incoming light-wave can be shaped to almost any desired form. In this way, the light propagating away from the metasurface can be controlled accurately.
Metasurfaces are intrinsically wavelength dependent, which make them currently best suited for monochromatic applications, although great efforts are invested in the research community to improve the broadband behavior.