Transmission optimized LWIR metalens

Thermal imaging at the infrared wavelength regime has long been applied to different areas such as agriculture and defense industries. Metasurfaces, 2D engineered ultra-thin structures, have attracted much attention due to their compact size, superior performance, and different functionalities at optical frequencies. This work details the design and fabrication of high transmission metalenses operating at the long-wave infrared (LWIR) spectrum. We minimize the reflection losses through anti-reflection coating (ARC) while maintaining the full wavefront control at the central wavelength 9.07 mu m. Our unit cell structure provides an average transmission of 97.5%. We experimentally verify our results and show that the fabricated metalenses perform diffraction-limited imaging at the design wavelength.(c) 2022 Optica Publishing Group https://doi.org/10.1364/AO.469805

Automated summary

This work presents the design and fabrication of high transmission metalenses operating at the long-wave infrared spectrum. By employing an anti-reflection coating, the reflection losses are minimized while maintaining full wavefront control at the central wavelength. Experimental results demonstrate diffraction-limited imaging of the fabricated metalenses at the design wavelength.