Latest advancements at NILT on flat metalens based camera modules in near infrared

NIL Technology (NILT) is an optical solutions company designing, developing, and manufacturing flat optical elements and components with nanoscale features such as diffractive optical elements (DOEs) and meta optical elements (MOEs). NILT’s MOE lenses have recently demonstrated a groundbreaking 94% absolute efficiency at 940 nm. This major milestone, in combination with other efforts such as the subsequent module integration and enabling of mass production of MOE elements, are among the key development areas for successful adoption of MOE lenses in various markets, ranging from consumer to automotive and applications such as sensing and machine vision systems. Here, we report our recent achievements with a camera module based on an MOE lens. We have successfully designed and manufactured camera modules using a single MOE lens showing excellent performance compared to refractive lens counterparts. The design has a low f-number and extremely high relative illumination. Prototypes are prepared using e-beam lithography, whereas MOE lenses in mass production are manufactured using nanoimprint lithography. The characterization of the MOE lenses reveals full agreement with the simulated nominal design. Image artifacts can appear due to higher orders of diffraction if the MOE lenses are not designed and manufactured properly. To illustrate the promise for volume production, a tolerance analysis has been performed, where the system tolerance analysis shows yield versus performance. At the module level, a straylight study, including ghost image and finally, thermal stability has been analyzed. The tolerance and thermal analysis are not presented in this manuscript. These results show the advantages of using 'NILT's high-efficiency meta optical elements compared to traditional optical systems.