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This work focuses on developing a solution-based ultra-thin polarizer for liquid crystal displays, utilizing dichroic azo dye AD1 as the key material. The produced AD1 polarizer exhibits excellent optical performance with a dichroic ratio of over 95. The film thickness is less than 200nm. Furthermore, a TN LCD with an incell polarizer is demonstrated. This technology shows excellent prospects for developing high-performance, coatable polarizers with scalability and lower-cost manufacturing potential. © 2023, John Wiley and Sons Inc. All rights reserved.

An approach to developing a thin-film polarizer with high polarization efficiency in liquid crystal cells is presented. The in- cell polarizer facilitates the realization of novel color-conversion liquid crystal displays, where advanced quantum color-converters are used as photoluminescent color filter arrays. We experimentally demonstrated using azo-dye-based embedded polarizers for color-conversion liquid crystal displays for the first time. We systematically designed the device structure and fabrication process. The display is color parallax free and can be driven at regular conditions with good contrast. © 2023, John Wiley and Sons Inc. All rights reserved.

This work demonstrates a high-performance in-cell polarizer adopting photo-aligned azobenzene dyes. On the strength of the multilayered design, a simple fabrication process has been developed to assemble an in-cell polarizer. We have achieved a broadband dichroic ratio after the long-term stability test. Meanwhile, the cell with the proposed in-cell polarizer can be driven regularly without a voltage boost, which renders excellent practicability in liquid crystal display technologies. The structure, fabrication process, and properties of the in-cell polarizer in TN-LCD are thoroughly discussed. © 2023, John Wiley and Sons Inc. All rights reserved.

Ultrathin (<200nm) azo dye polarizing film with a high dichroic ratio (over 150) is developed by photo-alignment methods. Polarizing film prepared by solution-based process (post-photoalignment) and evaporation (in-situ photo-alignment) with a family of azo dye materials with slightly different molecular structures is explored. We study the photostability of these azo-dye films against polarized light. Methods and factors of getting high dichroic ratio and high photostability polarizing films are discussed. © 2023, John Wiley and Sons Inc. All rights reserved.

As amorphous oxide semiconductors (AOSs) are hotly pursued for advanced displays, flexible electronics, optoelectronics, and neuromorphic systems, the AOS Schottky barrier diodes (SBDs) have been tried only using the mainstream amorphous InGaZnO (a-IGZO) and the conservative bottom-anode structure. To deepen the study on AOS SBDs, the more challenging top-anode SBD is developed in this work using a versatile but vulnerable AOS, amorphous InZnO (a-IZO). Unsurprisingly, the Schottky interface defects are seriously increased by the top-anode process and the defective a-IZO, which cannot be effectively passivated using the incumbent oxidizing treatments. The hydrogenation is proposed to considerably suppress these annoying interface defects and thus correspondingly reduces the large leakage current, while the hydrogen doping easily deteriorates a-IGZO SBD. The underlying mechanism of such distinction is revealed to be the tricky interactions between defect and hydrogen in AOSs. Based on the sophisticated utilization of such defect-hydrogen interplay, the a-IZO/a-IGZO stack is hydrogenated together to simultaneously realize a high-conductivity bulk and low-defect interface, noticeably enhancing the performance metrics. Such top-anode SBD based on hydrogenated multilayer AOSs successfully blazes a novel evolution path for AOS SBDs.

The display industry has a sizable global market. In 2021, it had a value of $148.4 billion, and by 2026, it was predicted to be worth $177.1 billion. The display market includes liquid crystal displays (LCDs), organic light-emitting diodes (OLEDs), micro-light-emitting diodes (Micro-LEDs), e-books, and more. Each of them has advantages and disadvantages. People will choose different display technologies according to their intended usage. Nowadays, electronic ink (E-ink) display technologies are very popular in e-books. Compared to other types of displays, one of their numerous advantages is that they are more similar to printing paper. This makes them easier to see with eyes and readable in direct sunlight. Additionally, they consume less power than other displays and are flexible in size. In e-books display technologies, the reduction of power consumption is mostly due to bistability. In this research, based on a novel type of bistable LCD, we can repeat these properties and even achieve lower driving voltages than existing E-ink technologies. Our group has many years of experience in the research of bistable liquid crystal displays. Many new bistable display technologies have been invented in our laboratory. Playing animations wasn't one of our major developments when we first invented bistable displays. The well-known disadvantage of bistable LCD and E-ink is the slow switching speed. Such a low frame rate is not enough to play animations. In this thesis, we propose a new method for fabricating fast-switching bistable liquid crystal displays capable of playing animations.

A composite photoalignment layer for aligning liquid crystal molecules includes: a monomeric material; a photoinitiator or a thermal initiator; and an azo dye material. A method for preparing a composite photoalignment layer for aligning liquid crystal molecules includes: mixing, in solution form, a monomeric material, a photoinitiator or a thermal initiator, and an azo dye material; coating the mixed solution onto a substrate to form a thin film; exposing the thin film to polarized light; and, with a thermal initiator, heating the thin film to polymerize the monomeric material and form a solid thin film.

Stable ferroelectric liquid crystal (FLC) elements have been realised by optically stabilised alignment film and thermally stabilised alignment film. The two methods of fabricated FLC elements have been explored for different aspects, namely alignment quality, electro-optical response and their possibility for complicate aligning patterns such as grating and Pancharatnam–Berry lens. They are compared based on different requirements of applications. With these two approaches, we are able to produce various types of FLC photonic and display devices with good photostability. © 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group.

Self-powered smart windows are desirable with the expectations of their energy-saving, weather-independent, user-controllable, and miniature performance. Recently developed solar- or thermal-powered smart windows largely depend on the weather conditions and have an extremely slow response, and only a certain portion of the saved energy can be utilized by the external circuit for mode conversion. In this work, a self-powered normally transparent smart window was developed by the conjunction of a rotary freestanding sliding triboelectric nanogenerator (RFS-TENG) and a polymer network liquid crystal (PNLC) cell. To fabricate the PNLC cell, the alignment layer with randomly distributed microdomains was constructed to encapsulate a mixture of LC polymers and nematic LCs. The opacity of the smart window exposed to an alternating electric field was considerably improved owing to the embedded microdomains and a dense web of LC polymers. The ultrahigh haziness greatly alleviates the charge density required for the LC actuation and thus enables the driving by the TENG where the charge amount is usually limited. The RFS-TENG was elaborately designed with six periodic bent triboelectric films and Ag electrodes, which presented an ultralow friction wear and met the frequency requirement to achieve the steady opacity. By harvesting the mechanical energies from ambient environments, the tribo-induced smart window can benefit a wide variety of fields, such as self-powered sunroofs, wind-driven smart farming systems etc. Copyright © 2020 American Chemical Society.

In this article, we present a high performance smart window via micro‐domains manipulation on the alignment surface, which dramatically enhances the power‐on haze by 48%. Large‐scale window with ultra‐hazy state switching in less than 3.5 ms is demonstrated.

Photoalignment is one of the best candidates of the proven market for multi domain display. It allows nearly free pattern to the liquid crystal alignment direction compared to the conventional rubbed polyimide. Most of the available photoalignment materials require polarized deep UV irradiation with a finite dosage. With the consideration of the current limitation with such a small working window, a vertical photoalignment surface by non‐polarized LED light irradiation with large wavelength is proposed and demonstrated. The alignment direction of proposed surface is generated by the inclined non‐polarized light. The measurement results show the alignment properties of this proposed alignment surface are comparable to conventional polyimide. It has stable and uniform pretilt angle, high polar anchoring energy and fast response time. As a result, the proposed alignment layer is robust and especially suitable for large‐area liquid crystal displays which require high performance with stable pretilt angles and multi‐domain purposes.

We propose here a novel multi-layered waveguide liquid crystal (LC) smart window with full color rendering based on a polymer-network liquid crystal system. The inserted position of three-primary-color LED light bars is specially designed, which is parallel to the LC alignment to obtain a higher difference between transparent and scattering states. The optimal matching of polymer-network LC system is experimentally achieved by comparing several groups of LC and reactive mesogen materials. The prepared smart window is measured and analyzed in detail including optical/chromatic test, morphology characterization, and actual application effect. The proposed architecture opens up new prospects of flexible color switchable ability and synchronized full-color display for smart windows without limitations of slow LC response time and complicated field sequential driving scheme.

The Polymer Network Liquid Crystal (PNLC) cell we fabricated is operating in a reverse mode of voltage‐off transparent state. It is found that when we apply voltage to the PNLC cells, the transmitted light color changed gradually and finally became a bit blue. This effect is not found in Polymer Dispersed LC (PDLC) window. The wavelength dependent transmittance voltage curves are reported and we will try to explain this effect by applying the anomalous diffraction theory.

Photoalignment is evaluated by the proven market for patterned alignment display. The performance of photoalignment is demonstrated to be equivalent to rubbed alignment. It allows nearly free pattern to the liquid crystal alignment direction compared to the conventional rubbed polyimide. Most of the available photoalignment materials require polarized deep UV irradiation with a finite dosage. With the consideration of the current limitation with such a small working window, a vertical photoalignment surface by non-polarized blue LED light irradiation is proposed and demonstrated. The alignment direction of proposed surface is generated by the inclined non-polarized light. The measurement results show the alignment properties of this proposed alignment surface are comparable to conventional polyimide. It has good stability and performance in terms of uniform pretilt angle, high polar anchoring energy and fast response time.

The Polymer Network Liquid Crystal (PNLC) cell we fabricated is operating in a reverse mode of voltage‐off transparent state. It is found that when we apply voltage to the PNLC cells, the transmitted light color changed gradually and finally became a bit blue. This effect is not found in Polymer Dispersed LC (PDLC) window. The wavelength dependent transmittance voltage curves are reported and we will try to explain this effect by applying the anomalous diffraction theory.

Photoalignment is one of the best candidates of the proven market for multi domain display. It allows nearly free pattern to the liquid crystal alignment direction compared to the conventional rubbed polyimide. Most of the available photoalignment materials require polarized deep UV irradiation with a finite dosage. With the consideration of the current limitation with such a small working window, a vertical photoalignment surface by non‐polarized LED light irradiation with large wavelength is proposed and demonstrated. The alignment direction of proposed surface is generated by the inclined non‐polarized light. The measurement results show the alignment properties of this proposed alignment surface are comparable to conventional polyimide. It has stable and uniform pretilt angle, high polar anchoring energy and fast response time. As a result, the proposed alignment layer is robust and especially suitable for large‐area liquid crystal displays which require high performance with stable pretilt angles and multi‐domain purposes.

In this article, we present a high performance smart window via micro‐domains manipulation on the alignment surface, which dramatically enhances the power‐on haze by 48%. Large‐scale window with ultra‐hazy state switching in less than 3.5 ms is demonstrated.

Photoalignment is evaluated by the proven market for patterned alignment display. The performance of photoalignment is demonstrated to be equivalent to rubbed alignment. It allows nearly free pattern to the liquid crystal alignment direction compared to the conventional rubbed polyimide. Most of the available photoalignment materials require polarized deep UV irradiation with a finite dosage. With the consideration of the current limitation with such a small working window, a vertical photoalignment surface by non-polarized blue LED light irradiation is proposed and demonstrated. The alignment direction of proposed surface is generated by the inclined non-polarized light. The measurement results show the alignment properties of this proposed alignment surface are comparable to conventional polyimide. It has good stability and performance in terms of uniform pretilt angle, high polar anchoring energy and fast response time.

A front polarizer-free optically rewritable (ORW) liquid crystal displays (LCDs) has been made via a hybrid alignment configuration with dye-doped LCs. The hybrid structure consists of one optically active planar and one optically passive homeotropic alignment layer. The rewritability of the device is achieved by photo- reorienting the azo dye molecules in the active planar alignment layer. The dye doped in LCs function as a polarizer by following the LCs alignment via a guest-host effect so that the front polarizer can be eliminated. This makes the device more compact and easier to operate for image erasing and rewriting. The image rewriting time only requires ~9.0s, which is determined by the exposure energy and LC parameters. The hybrid-mode dye-doped optically rewritable (DDORW) LCD devices could find applications in E-paper, transparent display and various photonics devices.

In this article, two different azo dye stabilization methods were demonstrated. One is realized by two-step exposure while the other is simplified one-shot irradiation on a thin film. Various stabilization methods provide more flexibility on alignment layer preparation. Both methods offer an alignment layer with highly acceptable thermal and photo-stability. © 2018 International Display Workshops. All rights reserved.