Fig. 7: The broadband infrared imaging of various targets.
From: Broadband infrared imaging governed by guided-mode resonance in dielectric metasurfaces
a The image of the target and metasurface under white light source illumination. b–d Transformed visible images of the target via metasurfaces under signal and pump beam illumination with the signal and FWM wavelengths (top: λs, bottom: λFWMp + λ′FWMp). The pump wavelength is fixed at 1130 nm. e Image of the sample with ’NTU’ marking under white light source illumination. f Transformed visible image of the ’NTU’ marking via the Si metasurface under signal and pump beam illumination with the signal and FWM wavelengths. The pump wavelength is fixed at 1130 nm. g Image of the biological sample under white light source illumination. h Transformed visible image of the ’NTU’ marking via the Si metasurface under signal and pump beam illumination with the signal and FWM wavelengths. The pump wavelength is fixed at 1130 nm
