Guijun Li

Dr.Guijun Li is currently an assistant professor in the college of physics andoptoelectronic engineering at Shenzhen University, and also the vice-director of Key Laboratory of Optoelectronic Devices and System, Ministry of Education,Shenzhen University. He received his BS and MS degree in Electrical Engineering from Nankai University. He then studied with Prof. Hoi-Sing Kwok at Hong Kong University of Science and Technology (HKUST), where he received his PhD degreein Electronic and Computer Engineering. He has co-founded the Intelligent Optics (HK) Ltd, served as the technical consultant of Hanergy (Chengdu), andthe Research Associate of State Key Laboratory of Advanced Displays and Optoelectronics Technologies of HKUST. He has published over 70⁺journal papers/conference proceedings and co-authored 15 patents with 10 granted. His current research focuses on the advanced display, mainly involving in device-level engineering towards multifunctional/intelligent information display.

---------------------------------------------------------------------------

Pixel­-level Engineering towards Intelligent Displays

With the gradual maturity of new technologies such as 5G, artificial intelligence(AI), internet of things (IoTs), and autonomous driving, the development of information displays with multiple functionalities is an attractive feature toenable enhanced unique user interfaces and interactivity. The basic technology-related requirement of the intelligent display is the ability of transmitting and receiving information or signal in the form of visible light.However, integrating the functionalities of the information transmitter and signal receiver into pixel arrays of a display panel is challenging, becausethe sub-pixel of an emissive display cannot perform simultaneous visible light generation and reception very well. Electrically, the charge injection for lightemission and charge separation/exciton dissociation for light detection is a conversephysical process. It is difficult for the conventional design for the device with a single active layer to achieve efficient charge extraction and chargeinjection simultaneously, as the structure is presupposed to facilitate onlyone-directional transport. Optically, it is difficult to use a light-emitting device for sensitive weak light detection, as the ultrathin thickness of the light-emitting device cannot guarantee sufficient light absorption. In this talk, we will talk about the work we have done to address the above electrical and optical issues for the development of light-responsive light-emitting diodes for multifunctional displays. First, we will demonstrate alight-emitting device with integration of proof-of-concept functions of information displaying, signal sensing, and energy harvesting. Second, we will show alight-emitting device that is capable of ultrasensitive weak light detection,by coupling the light response of photovoltage to the gate of a double-gate TFT to amplify the signal.