The use of sub-optical surface features for functional soft-matter devices
Lead Research Organisation:
University of Leeds
Department Name: Physics and Astronomy
Abstract
The next generation of liquid crystal devices will be used in a range of applications including adaptive optics (switchable lenses, beam steerers, phase controllers, switchable holograms) and Virtual / Augmented Reality displays. This project aims to explore additional functionalities to such devices, through the design of sub-optical and nanoscopic features on the contacting surfaces of the liquid crystal. These functionalities include multi-stability, photonic and plasmonic effects. The work is supported by the industrial companies Merck and NVD Ltd.
Initial tests have used electron-beam lithography to fabricate profiled structures on the inner surfaces of liquid crystal devices. The aim is to add functionality to the device, such as producing bistable stable alignment states. The structures need a near sinusoidal shape with controllable blaze, but with an amplitude to pitch ratio of greater than 1. Initial tests succeeded in making 400nm and 300nm pitch gratings (see figure) with the correct shape except but with insufficient amplitudes to produce bistability. However, a number of novel methods for increasing the amplitude have been suggested, and will form the starting point for the successful student working on this project.
Such structures have a real practical purpose, since they would allow higher reflectivity displays to be produced by the company NVD, and importantly allow dual mode LCD / OLED devices for portable applications. However, there is potential for a wealth of longer-term invention using 2D photonic surface structures [1] combined with liquid crystals to allow for full reconfigurable elements with other functionalities, including optical switching, bistable and multistable structures, interactions between lasing structures and topological defects. The area of application that interests industrial partner Merck is in novel Augmented Reality Displays.
The project is best suited to an experimental student that is proficient with some theory. The successful candidate will benefit from interactions with industrial companies including Merck and NVD Ltd, as well has a strong interaction engineering and working in their state-of-the-art cleanroom facility.
Initial tests have used electron-beam lithography to fabricate profiled structures on the inner surfaces of liquid crystal devices. The aim is to add functionality to the device, such as producing bistable stable alignment states. The structures need a near sinusoidal shape with controllable blaze, but with an amplitude to pitch ratio of greater than 1. Initial tests succeeded in making 400nm and 300nm pitch gratings (see figure) with the correct shape except but with insufficient amplitudes to produce bistability. However, a number of novel methods for increasing the amplitude have been suggested, and will form the starting point for the successful student working on this project.
Such structures have a real practical purpose, since they would allow higher reflectivity displays to be produced by the company NVD, and importantly allow dual mode LCD / OLED devices for portable applications. However, there is potential for a wealth of longer-term invention using 2D photonic surface structures [1] combined with liquid crystals to allow for full reconfigurable elements with other functionalities, including optical switching, bistable and multistable structures, interactions between lasing structures and topological defects. The area of application that interests industrial partner Merck is in novel Augmented Reality Displays.
The project is best suited to an experimental student that is proficient with some theory. The successful candidate will benefit from interactions with industrial companies including Merck and NVD Ltd, as well has a strong interaction engineering and working in their state-of-the-art cleanroom facility.
Organisations
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/T517860/1 | 01/10/2020 | 30/09/2025 | |||
| 2435135 | Studentship | EP/T517860/1 | 01/10/2020 | 31/03/2024 | Thomas Moorhouse |