The human eye is so hugely complex it uses the retina for visual processing. Our retina contains cone cells sensitive to red, green, and blue light and a neural network that starts processing what we see before the information is transmitted to our brain. Scientists have spent decades trying to replicate the structure of a biological eye.
Now scientists from Penn State have developed a new device that creates images by mimicking the human eye’s red, green, and blue cone cells and neural networks.
This artificial device consists of a new sensor array from narrowband perovskite photodetectors, which mimic our cone cells, and combine them with a neuromorphic algorithm that mimics our neural networks to process information and produce high-fidelity images.
Scientists have created three different thin-film perovskite materials. The materials are designed to be sensitive to red, green, or blue colors with heavily unbalanced electron-hole transport. By manipulating the architecture of unbalanced perovskites or how the layers are stacked, the scientists found they could harness the material’s properties rather than turning it into narrowband photodetectors.
They built a sensor array with red, green, and blue thin-film perovskite material. They used a projector to flash images through the device. The information collected in the red, green, and blue layers was fed into a three-sub-layer neuromorphic algorithm for signal processing and image reconstruction. A neuromorphic algorithm is a type of computing technology that attempts to imitate the operation of the human brain.
The new devices generate energy by absorbing light as the scientists used a perovskite material. Therefore, we do not need to use energy to capture this information from light. This device may open the door to battery-free camera technology.
According to scientists, devices based on this technology could one day replace dead or damaged cells in our eyes. This research could stimulate further development in artificial retina biotechnology.
The Air Force Office of Scientific Researchers funds this research. Also, this project is supported by the U.S. Department of Energy, the National Institute of Food and Agriculture, and the National Science Foundation.
- Yuchen Hou, Junde Li, Jungjin Yoon, Abbey Marie Knoepfel, Dong Yang, Luyao Zheng, Tao Ye, Swaroop Ghosh, Shashank Priya, And Kai Wang. Retina-inspired narrowband perovskite sensor array for panchromatic imaging. Science Advances, 2023; DOI: 10.1126/sciadv.ade2338