Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China.
State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, Nanjing, 210023, China.
Nat Commun. 2023 Apr 21;14(1):2281. doi: 10.1038/s41467-023-37973-0.
Sensing and recognizing invisible ultraviolet (UV) light is vital for exploiting advanced artificial visual perception system. However, due to the uncertainty of the natural environment, the UV signal is very hard to be detected and perceived. Here, inspired by the tetrachromatic visual system, we report a controllable UV-ultrasensitive neuromorphic vision sensor (NeuVS) that uses organic phototransistors (OPTs) as the working unit to integrate sensing, memory and processing functions. Benefiting from asymmetric molecular structure and unique UV absorption of the active layer, the as fabricated UV-ultrasensitive NeuVS can detect 370 nm UV-light with the illumination intensity as low as 31 nW cm, exhibiting one of the best optical figures of merit in UV-sensitive neuromorphic vision sensors. Furthermore, the NeuVS array exbibits good image sensing and memorization capability due to its ultrasensitive optical detection and large density of charge trapping states. In addition, the wavelength-selective response and multi-level optical memory properties are utilized to construct an artificial neural network for extract and identify the invisible UV information. The NeuVS array can perform static and dynamic image recognition from the original color image by filtering red, green and blue noise, and significantly improve the recognition accuracy from 46 to 90%.
感知和识别不可见的紫外 (UV) 光对于开发先进的人工视觉感知系统至关重要。然而，由于自然环境的不确定性，很难检测和感知 UV 信号。在这里，受四色视觉系统的启发，我们报告了一种可控的紫外超敏感神经形态视觉传感器 (NeuVS)，它使用有机光电晶体管 (OPTs) 作为工作单元，集成了传感、存储和处理功能。得益于有源层的不对称分子结构和独特的 UV 吸收，所制备的紫外超敏感 NeuVS 可以检测到 370nm 的紫外光，其光照强度低至 31nW/cm，在紫外敏感神经形态视觉传感器中具有最佳的光学性能之一。此外，由于其超灵敏的光学检测和高密度的电荷俘获态，NeuVS 阵列表现出良好的图像传感和记忆能力。此外，利用波长选择性响应和多级光存储特性，构建了一个人工神经网络，用于提取和识别不可见的 UV 信息。NeuVS 阵列可以通过滤除红、绿、蓝噪声来对原始彩色图像进行静态和动态图像识别，从而将识别精度从 46%显著提高到 90%。
