Fig. 4: Imaging using the BAC-eye.

a Workflow for image acquisition and processing by the BAC-eye. The colour scale represents the intensity level of the detected signals. b Schematic diagram of the experimental setup of the imaging system. c The square mask used for image detection experiments. d The illuminated square pattern as detected by the BAC-eye. The image of the illuminated pattern on the artificial ommatidia is captured by a single-lens reflex (SLR) camera equipped with a macro lens. e The square pattern image captured from the bottom of BAC-eye. f The digitally reconstructed hemispherical image. g Illustration of the hemispherical imaging for a red cross pattern whose centre is fixed at an angular position of (α = 60°, β = 0°) and a blue triangular pattern moving from the side (α = 85°, β = 180°) toward the red cross. h–j The reconstructed images showing the triangle as it travels from (α = 60°, β = 180°), (α = 40°, β = 180°), and (α = 20°, β = 180°). The digitally generated callouts provide stereoscopic vision (for a human observer) of the hemispherical images.