In their implementation, the researchers packed 281 hexagonally-shaped photodetectors (each 113 μm in diagonal) in hemispherical arrays of different radii, 2.27mm and 7.20mm, only observing a performance degradation when the photodetector was conformed to a curvature radius of 1.5mm. But they note that if made thinner (down to 20nm), a silicon nanomembrane photodetector could easily wrap around a single mode fibre (125μm in diameter).
The hemispherical FPA was assembled into a simple camera system featuring a plano-convex lens (10mm diameter and 10mm focal length) while the convex version was evaluated as a compound eye mimicking camera (a photoresist microlens placed on top of each detecting unit during fabrication to maximize light intake).
The paper highlights the simplicity of the origami-shaping process and how easily the pixel density could be scaled up. The researchers hope that further optical optimizations of their compound electronic eye system (such as adding layers to mimic the pigment cells and crystalline cones) could yield truly panoramic colour vision.
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