Metalenses are flat lenses that use metasurfaces to focus light. The metasurfaces themselves are structures that work like optical antennae, which can manipulate how light interacts with the surface.
The development of metasurfaces has helped to open up opportunities for the creation of new types of optical components with new and exciting applications, from sensing in medicine to imaging and consumer electronics, such as smartphones and AR/VR systems. According to market intelligence firm, ResearchAndMarkets.com, the market for metamaterials is a fast-developing area and could be set to become a multi-billion dollar market within the next 10 years. The company’s latest report, The Global Market for Metamaterials and Metasurfaces to 2033 predicts there could be advances in radar and lidar for autonomous vehicles, telecommunications antenna, 6G networks, coatings, vibration damping, wireless charging, noise prevention and more.
For optical design engineers, R&D engineers, scientists, semiconductor foundries, research institutes and other organisations interested in metalens technologies, there is a world of possibilities. They have the potential to help with the all-important minimisation of optical products by replacing bulkier curved lenses with thin, flat surfaces and improving optical stability and quality of focus over more conventional lenses. The report also cites them as a key enabling technology for the next generation of compact imaging, sensing and display applications. They have the added advantage of being able to perform quite intricate wavefront engineering in a single optic that is highly appealing for a range of applications.
The challenges
But they don’t come without their challenges. Rob Scarmozzino, Scientist at Synopsys, explains: “Designing metalens systems typically requires deep physics knowledge and significant design experience. In addition, it can be very challenging to meet multiple specifications, including achromaticity, large field of view and polarisation behaviour with just a single metalens. These specs can be achieved with a multi-metalens or hybrid traditional/metalens system, but this makes it very difficult to design using conventional methods that rely on knowing the necessary phase profile for each lens. Furthermore, the latter approach over-constrains the design, possibly resulting in less-than ideal performance.”
To help this demographic overcome the challenges associated with designing metalenses, Synopsys invested in the development of a new and novel approach to metalens design, which removes traditional barriers to this technology. The fully automated technology, called MetaOptic Designer, can dramatically simplify metalens design complexity. Scarmozzino says: “With minimum inputs required, designers at all levels can create novel metalens designs quickly and easily.”
The solution
The key design-enabling features of the MetaOptic Designer tool include its ability to simultaneously consider multiple design goals incorporating different launch/ target fields and performance metrics in the context of mixed optical systems composed of multiple metasurface and conventional lenses. Scarmozzino elaborates: “The simulation is field-based rather than ray-based, and incorporates rigorous coupled wave analysis (RCWA) and/ or FDTD modelling of the meta-atoms via our unique parametric, bi-directional scattering distribution function (BSDF) database technology. Optimised designs can be re-evaluated rapidly under different conditions, allowing tolerancing studies to be performed. Final design GDS is automatically generated for manufacture.”
The company certainly has the expertise behind them to develop such an ambitious solution, having been the ‘silicon to software’ partner for companies that develop electronic products, software applications and more since 1986. Members of the executive management team have a wide range of global backgrounds, with a great many decades of combined semiconductor industry experience.
Synopsys optical design technologies have been developed to maximise productivity for optical design engineers, R&D engineers, scientists, research institutes and more. This, in turn, helps that demographic to make sure they have the best quality in terms of results, so optical systems are optimised for performance, manufacturability and even cost.
When it comes to metalenses, the company’s recently developed new tool has built-in engineering intelligence, which allows designers at all levels of expertise to create novel metalens designs quickly and easily. Meanwhile, the efficient optimisation and simulation algorithms generate accurate results, validated by a rigorous finite-difference time-domain (FDTD) method and the powerful and user-friendly features significantly reduce design-to-validation cycles.
Scarmozzino believes that with advances in technology and developments such as the MetaOptic Designer, the use of metalenses could grow even further in the future, with more potential use cases opening up. He says: “The flexibility of the tool to explore new concepts prior to manufacture helps broaden the scope of potential applications for metalens technology. As the number of applications for these technologies grow, so will competition for designers. Powerful design tools will be needed to make these individuals more productive so they can meet growing market demands. MetaOptic Designer is just one technology needed for the growing space of applications in AR/VR, cell cameras [and] integrated sensors/sources. It is part of a larger optical design platform that includes LightTools, Code V, RSoft DiffractMOD RCWA, FullWave FDTD, and other photonics design tools that together can address many of these design needs.”
Find out more information about how Synopsys is supporting metalens innovation with MetaOptic Designer by downloading the latest White Paper.