香港科技大学Kristiaan Neyts教授和Vladimir G. Chigrinov教授学术报告

香港科技大学Kristiaan Neyts教授学术报告

报告时间：2024年10月24日（周四），09：15-10：00

报告地点：金沙2004路线js5光电大楼502多功能厅

报告题目：Patterned photoalignment for nanoscale geometric phase diffractive optics

邀请人：郑继红教授

摘要：Azo-dye materials are photosensitive and can be used for patterned photoalignment. Complex high-resolution illumination patterns are realized by interferometry or by projecting the pixels of a spatial light modulator. The patterning can be used to realize complex director structures in nematic, cholesteric, blue phase and ferro-electric nematic liquid crystals.

报告人简介：

Kristiaan Neyts is professor at the Hong Kong University of Science and Technology (HKUST) in the Department of Electronic and Computer Engineering (ECE) and Director of the State Key Laboratory of Advanced Displays and Optoelectronics Technologies (SKLADT) since September 2023. He received a degree in physics engineering in 1987, a doctoral degree in engineering in 1992 and became professor at Ghent University in the ELIS department in the faculty of Engineering and Architecture in 2000, after post-doctors in Ghent and at UC Berkeley. He is co-author of over 300 scientific papers and promotor or co-promotor of 30 completed PhDs.

香港科技大学Vladimir G. Chigrinov教授学术报告

报告时间：2024年10月24日（周四），10：00-10：45

报告地点：金沙2004路线js5光电大楼502多功能厅

报告题目：Azodye photoaligned nanolayers for liquid crystals: new applications

邀请人：郑继红教授

摘要：Photoalignment and photopatterning has been proposed and studied for a long time^[1].  Light is responsible for the delivery of energy as well as phase and  polarization information to materials systems. It was shown that  photoalignment liquid crystals by azodye nanolayers could provide high  quality alignment of molecules in a liquid crystal (LC) cell. Over the  past years, a lot of improvements and variations of the photoalignment  and photopatterning technology has been made for photonics applications.  In particular, the application of this technology to active optical  elements in optical signal processing and communications is currently a  hot topic in photonics research^[2]. Sensors of external  electric field, pressure and water and air velocity based on liquid  crystal photonics devices can be very helpful for the indicators of the  climate change.

We  will demonstrate a physical model of photoalignment and photopatterning  based on rotational diffusion in solid azodye nanolayers. We will also  highlight the new applications of photoalignment and photopatterning in  display and photonics such as: (i) fast high resolution LC display  devices, such as field sequential color ferroelectric LCD; (ii) LC  sensors, including polarization sensors for polarimetric cameraas;  (iii) LC lenses with a variable focal distance; (iv) LC E-paper  devices, including electrically and optically rewritable LC E-paper; (v)  photo induced semiconductor quantum rods alignment for new LC display  applications; (vi)100%  polarizers based on photoalignment; (vii) LC smart windows based on  photopatterned diffraction structures; (vii) LC antenna elements with a  voltage controllable frequency.

Acknowledgements

[1] V.G. Chigrinov, V.M. Kozenkov and H.S. Kwok, Photoalignment of liquid crystalline materials, Wiley, 2008.

[2] V.G. Chigrinov, Liquid Crystal Photonics, Nova Science Publishers, 2015.

报告人简介：

Professor Vladimir G. Chigrinov is  Professor of Hong Kong University of Science and Technology since 1999.  He is an Expert in Flat Panel Technology in Russia, recognized by the  World Technology Evaluation Centre, 1994, and SID Fellow since 2008. He  is an author of 6 books, 31 reviews and book chapters, about 333 journal  papers, more than 718 Conference presentations, and 121 patents and  patent applications including 50 US patents in the field of liquid  crystals since 1974. He got Excellent Research Award of HKUST School of  Engineering in 2012.He obtainedGold Medal and The Best Award in the Invention & Innovation Awards 2014 held at the Malaysia Technology Expo (MTE) 2014, which was hosted in Kuala Lumpur, Malaysia, on 20-22 Feb 2014. He is a Member of EU Academy of Sciences (EUAS)  since July 2017. He got A Slottow Owaki Prize of SID in 2018. He is  2019 Distinguished Fellow of IETI (International Engineering and  Technology Institute).

Since  2018 until 2020 he works as Professor in the School of Physics and  Optoelectronics Engineering in Foshan University, Foshan, China.  2020-2024 Vice President of  Fellow  of Institute of Data Science and Artificial Intelligence (IDSAI) Since  2021 distinguished Fellow of Institute of Data Science and Artificial  Intelligence. He is IETI Fellowsince 2019.Since  March 2022 he is A Fellow of National Academy of Technology for his  contributions to Information Electrical and Electronic Research. He is a Editor in Chief of Liquid Crystal section in Crystals journal since 2023.