Goniometric Investigation of Spectral Scattering From Insect Wings in Near Infrared

Insect wing interference is highly sensitive to the membrane thickness and has shown remarkable potential to differentiate insect species, both <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ex vivo</i> in laboratory settings and for free-flying insects <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i>. While several studies have reported diversity of wing interference patterns, no study has linked this resonant coherent scattering from membranes to the goniometric scattering phase function. We present a combined spectral and goniometric study and demonstrate that resonant wavelengths for a species selectively communicate with the thin and flat wing membrane, whereas scattering at dissonant wavelengths to a greater extent arises from the tubular veins. This report lays the groundwork for a deeper understanding of range dependence in entomological lidar and insect differentiation based on spectral and modulation properties.