Cuttlefish eye–inspired artificial vision for high-quality imaging under uneven illumination conditions

Abstract

With the rise of mobile robotics, including self-driving automobiles and drones, developing artificial vision for high-contrast and high-acuity imaging in vertically uneven illumination conditions has become an important goal. In such situations, balancing uneven illumination, improving image contrast for facile object detection, and achieving high visual acuity in the main visual fields are key requirements. Meanwhile, in nature, cuttlefish (genus Sepia ) have evolved an eye optimized for vertically uneven illumination conditions, which consists of a W-shaped pupil, a single spherical lens, and a curved retina with a high-density photoreceptor arrangement and polarized light sensitivity. Here, inspired by the cuttlefish eye, we report an artificial vision system consisting of a W-shaped pupil, a single ball lens, a surface-integrated flexible polarizer, and a cylindrical silicon photodiode array with a locally densified pixel arrangement. The W-shaped pupil integrated on the ball lens balances vertically uneven illumination, and the cylindrical silicon photodiode array integrated with the flexible polarizer enables high-contrast and high-acuity imaging.

Evolution of natural eyes and biomimetic imaging devices for effective image acquisition

“…3c). 88 The photodiode array is then transferred onto a concave cylindrical PDMS mold and integrated with an artificial lens and aperture to fabricate the imaging device. The lens used in the device has a negative magnification, which forms an inverted image on the photodiode.…”

“…8a). 88 To fabricate the film, a mixture of single-wall carbon nanotubes (SWCNTs) and P(VDF-TrFE-CFE) was prepared and then subjected to a mild heat treatment while being mechanically stretched. This process obtained a film that was four times longer than its original length, and the SWCNTs were aligned within the composite material.…”

Mechanically-Guided 3D Assembly for Architected Flexible Electronics

“…Cameras in forms of biomimetic 3D eyeballs can significantly improve the imaging performance by offering broadened field of views, reduced distortions, and decreased chromatic aberrations. , Various eyeball cameras manufactured using mechanically-guided assembly methods were reported. ,,,,,,,,− …”

“…Apart from electronic compound eyes, eyeball cameras inspired by aquatic visions were reported as well. , For example, inspired by the vision of cichlid fish, miniaturized eyeball cameras (with a diameter of 11.5 mm) were developed, offering a large field of view (120°), a deep depth of field (20 cm), a low optical aberration, and a simple visual accommodation capability (Figure b) . Furthermore, a 3D eyeball camera inspired by the cuttlefish eye, consisting of a W-shaped pupil, a single ball lens, a surface-integrated flexible polarizer, and a highly integrated cylindrical silicon photodiode array that can maintain an average degree of polarization of ∼78% in the visible wavelength range, was able to perform high-quality imaging under uneven illumination conditions …”

“…426 Furthermore, a 3D eyeball camera inspired by the cuttlefish eye, consisting of a W-shaped pupil, a single ball lens, a surface-integrated flexible polarizer, and a highly integrated cylindrical silicon photodiode array that can maintain an average degree of polarization of ∼78% in the visible wavelength range, was able to perform high-quality imaging under uneven illumination conditions. 427 To improve the accommodation of cameras to the changes in the Petzval surface upon the use of different lenses, tunable hemispherical electronic eye camera systems with adjustable zooming capabilities were developed through curving-induced assembly. 101 In particular, these cameras employed deformable photodetector arrays on thin elastomeric membranes, which are capable of pneumatically controlled dynamic curvature adjustments.…”