Phys.org August 4, 2022
Various artificial visual systems including those based on human eyes, insect eyes and fisheyes have been developed. However, attempts to develop systems for both terrestrial and aquatic environments and bioinspired electronic eyes are restricted in their maximum field of view to a hemispherical field of view (around 180°). An international team of researchers (South Korea, USA – UT Austin, MIT) has developed an amphibious artificial vision system with a panoramic visual field inspired by the functional and anatomical structure of the compound eyes of a fiddler crab. They integrated a microlenses array with a graded refractive index and a flexible comb-shaped silicon photodiode array on a spherical structure. The microlenses have a flat surface and maintain their focal length regardless of changes in the external refractive index between air and water. The comb-shaped image sensor arrays on the spherical substrate exhibit an extremely wide field of view covering almost the entire spherical geometry. They illustrated the capabilities of their system via optical simulations and imaging demonstrations in both air and water…read more. TECHNICAL ARTICLE
Structural characteristics of the fiddler crab eye. Credit: Nature Electronics volume 5, pages 452–459 (2022)