Transparent Long-Pass Filter with Short-Wavelength Scattering Based on Morpho Butterfly Nanostructures

Abstract

We combine the principles of moth-eye antireflection, Bragg scattering, and thin-film interference to design and fabricate a short-wavelength scattering/long-pass filter with sharp cutoff, high transmission of infrared light, and strong reflection of visible light into high angles. Based on the lamellae-edge features on Morpho didius butterfly wings, nanostructures are self-assembled via sequential one-chamber chemical vapor deposition, metal nanoparticle formation, and wet-chemical etching. Finite-element modeling demonstrates strong (>45%) reflection into the first diffracted order for short wavelengths, while retaining >80% transmission for longer wavelengths. Fabricated nanostructures couple more than 50% of reflected light into angles of >10° while enabling broadband long-pass transmission. Such structures have potential applications in light trapping for tandem solar cells, stealth, and signals processing.

Mining the Smartness of Insect Ultrastructures for Advanced Imaging and Illumination

“…The structural coloration inspired by the wings of butterflies and beetles boasts optical properties such as iridescence, polarization caused by interference, scattering, and diffraction. In Figure , biologically inspired structures for structural coloration are anatomically categorized, depending on approach and process design from a single‐layer level, a multilayer level, a sculpture level, to a quasi‐ordered level . Textures on the layer itself, for example, holes, C‐grooves, and zigzags in Figure a, produce structural colors.…”

“…Zhang and Chen built aligned lamellae layers to mimic the iridescent blue of Morpho butterfly in Figure g . Lal et al fabricated conical lamellae‐edge nanostructure with sharp cutoff and strong reflection of visible light in Figure h . Thus, insect‐inspired structural coloration has been explored by emphasizing artificial materials and unconventional fabrication methods, shown in Table 2 .…”

“…Emulating natural compound eyes in a 2D planar substrate with photolithography was already demonstrated in 2012 . Complex 3D ultrastructures inspired by butterfly wing scales were reported, giving rise to a selective UV reflector . In addition, structures mimicking compound eyes have been prompted for curved and 3D artificial structures, for example, a digital camera holding a hemispherical, apposition compound eye, a miniaturized artificial compound eye device, 3D artificial compound eyes fabricated by femtosecond laser direct writing strategy with FOV wider than 180°, and recently, ultracompact 3D‐printed microlens arrays with high optical resolutions .…”

“…Wings as well as eyes of a butterfly serve as a distinctive structural color template, arisen from natural photonic crystals with multistacked layers . Advanced from biological structural coloration, a transparent long‐pass filter inspired by Morpho butterfly is nanofabricated by self‐assembly and ultrathin, porous methyl methacrylate (PMMA) films, inspired by the white beetle of Cyphochilus insulanus , provide consistent whiteness. Besides, various micro/nanostructures found in fireflies, moth eye, and compound eye make use of highly efficient light extraction to directly suit modern lighting technologies such as a light‐emitting diode (LED) and an organic light‐emitting diode (OLED).…”

Disposable Morpho menelaus Based Flexible Microfluidic and Electronic Sensor for the Diagnosis of Neurodegenerative Disease

“…These ordered structures have achieved numerous applications, such as in biochemical detection, optical sensors, energy storage, and tissue engineering . In particular, the typical natural structure of the Morpho menelaus ( M. menelaus ) wing has many applications because of the luminous iridescent colors produced when incident light interacts with periodic anisotropic nanostructures on the wing scales . In recent decades, various applications have been inspired by the Morpho butterfly wings owing to its unique structural and optical properties, e.g., in gas sensors, infrared sensors, and surface‐enhanced Raman spectroscopy substrates …”