A Retina-Like Dual Band Organic Photosensor Array for Filter-Free Near-Infrared-to-Memory Operations

5 years ago

A Retina-Like Dual Band Organic Photosensor Array for Filter-Free Near-Infrared-to-Memory Operations

Hongtao Liu, Yunlong Guo, Yanqiu Sun, Lifeng Wang, Zhenjie Ni, Hanlin Wang, Wenping Hu, Yunqi Liu, Ye Zou, Jie Yang, Qiang Zhao

Human eyes use retina photoreceptor cells to absorb and distinguish photons from different wavelengths to construct an image. Mimicry of such a process and extension of its spectral response into the near-infrared (NIR) is indispensable for night surveillance, retinal prosthetics, and medical imaging applications. Currently, NIR organic photosensors demand optical filters to reduce visible interference, thus making filter-free and anti-visible NIR imaging a challenging task. To solve this limitation, a filter-free and conformal, retina-inspired NIR organic photosensor is presented. Featuring an integration of photosensing and floating-gate memory modules, the device possesses an acute color distinguishing capability. In general, the retina-like photosensor transduces NIR (850 nm) into nonvolatile memory and acts as a dynamic photoswitch under green light (550 nm). In doing this, a filter-free but color-distinguishing photosensor is demonstrated that selectively converts NIR optical signals into nonvolatile memory. Using organic dye materials—both molecular and polymeric—a retina-like, filter-free photosensor with a near infrared (NIR) signal to nonvolatile memory is realized. The device features an integration of photosensing elements and floating-gate memories, and is capable of distinguishing 550-nm light and 850-nm light by a bimodal operation. This result provides innovation for intelligent photosensors with acute wavelength selectivity.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/adma.201701772