Scientists have developed an electrochemical eye with high resolution and speed of response. The lens they replaced the lens, vitreous — ion electrolyte, the retina on an array of nanowires light-absorbing perovskite, but instead of neurons used liquid metal wires of gallium and indium. This system successfully recognized the letters I, U, A and E. Work published in the journal Nature.
Human eye due to the hemispherical concave of the retina and sitopaladi components of the intraocular fluid have a wide field of view at 150-160 degrees, the high resolution of one angular minute (one sixtieth of a degree) and good adaptability. On this basis, scientists and engineers interested in the development of artificial analogue. It is expected to find application in robotics.
In the retina of the human eye located sticks (responsible for the emerald green region of the spectrum and provide scotopic vision) and cones (violet-blue, green-yellow and yellow-red region of the spectrum). Their density reaches ten million per square centimeter with an average step three micrometer, which creates such a high resolution. Today engineers produce available sensors based on the charge coupled devices and complementary structures of metal-oxide-semiconductor, which mainly uses a flat architecture because of the common process for production of flat chips. Such devices have already reached a similar permissive powers, but because of the technological complexity of the receiving device in the form of hemispheres practically realized. In addition, in recent years, scientists actively developed light-absorbing arrays of hybrid perovskites as photodetectors.
Fan Zhiyong (Zhiyong Fan) with colleagues from Hong Kong University of science and technology presented an artificial vision system based on electrochemical spherical eyes with hemispherical retina of a dense array of nanowires photosensitive hybrid perovskite. As an analogue of the vitreous they used ionic liquid electrolyte and the liquid metal wires were connected the light-sensitive structure with output contacts. This system showed a low limit of detection and wider field of view. Moreover, the photosensitive layer was more dense than the human eye, which increases the resolution of the visual system.