Meta optics replace conventional lenses

At the Hannover Messe, researchers from the Karlsruhe Institute of Technology (KIT) will be demonstrating an optical component that enables highly efficient light control at steep angles of incidence, overcoming previous limitations.

Conventional convex lenses, which direct light by refraction in glass or plastic, are often bulky, heavy and offer limited control over light waves. Meta-surfaces, on the other hand, are flat and consist of an array of tiny structures called meta-atoms. Metaatoms influence light on sub-wavelength scales, allowing for high-precision control of light, such as phase, amplitude and polarization. "With metasurfaces, we can therefore specifically influence the temporal shift, intensity and direction of oscillation of light waves," explains Dr. Maryna Leonidivna Meretska, group leader at the Institute of Nanotechnology at KIT. "Thanks to its ability to multiplex control, i.e. the simultaneous and targeted influencing of different parameters, a single metasurface can replace several optical components. This allows the size of the optical system to be reduced without compromising its performance." Production will also be simpler: "They are manufactured using advanced lithography and etching technologies from the semiconductor industry, which enables scalable production," says Maretska.

At the Hannover Messe, Meretska and her team are presenting an optical diffraction meta-grating that was produced using special KIT manufacturing equipment. Diffraction gratings are essential optical components for various industrial applications, such as spectroscopy, telecommunications and laser systems. Typically, the efficiency of diffraction gratings decreases sharply as the angle of incidence of the light increases. However, the metagrid developed at KIT shows a fourfold increase in efficiency compared to conventional systems. "Our metagrid enables unprecedented control over light under challenging conditions. This represents a significant advance for future applications that require precise light control," says Meretska. Now that the functionality has been proven with the prototype, the research group is developing targeted optical solutions for various industrial applications.

Due to their flat structure, meta-optics are particularly suitable for cameras, sensors and augmented reality displays, as they offer improved functionality and can also reduce the size of optical systems. Other potential applications include material sorting and quality control, medical imaging, microscopy and solar cells. In addition, robotics and autonomous driving, which rely on object recognition, could benefit from meta-optics.

Hanover Fair, Hall 2, Stand B35