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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.

We demonstrate a kind of in-cell solution-processed broadband circular polarizer made of liquid crystal polymer and a photo-aligned polarizer on top, using the coating technique and chemical treatment. The transmittance and reflectance spectrum shows a high ambient contrast ratio (ACR) improvement for the light-emitting display system. © 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.

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.

In this article, growth of GaN thin film on low-cost electronic substrate (n-Si) by magnetron sputtering method was reported. Growth parameters of GaN thin film have been studied based on different flow rate of sputtering gasses, chamber pressure, sputtering power, substrate temperature and duty ratio of pulse signals. Characterization techniques such as X-ray diffraction (XRD), micro photoluminescence (µ-PL), raman spectroscopy, transmittance, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) were performed to explore the optical and structural properties. XRD studies confirmed the wurtzite structure of grown thin film with the preferentially orientation along (002) plane, it also reveals the effect of growth parameters on the grain size and crystal quality of thin films. E2 (high) and A1 (LO) modes were observed in raman spectrum. Room temperature µ-PL and optical transmittance shows the near band edge (NBE) and sharp transmission edge around ∼3.3 eV relates to the band gap value of GaN structure. © 2021

A composite photoalignment layer for aligning liquid crystal molecules includes: a monomeric material; a photoinitiator or a them叫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.

Broadband quarter wave plates are widely used in optical system, especially in display system. Above all, a broadband quarter wave plate can be treated as an isolator in display to provide “perfect” dark state so as to improve the contrast ratio. A kind of broadband quarter wave plate combined by two waveplates with angle deviated is proposed and manufactured in this paper using coating technique. Two methods of combination of the two waveplate are proposed and tried. The reflection spectrum shows that this kind of structure can provide good dark state in display system.

Azobenzene materials provide an effective way for liquid crystal (LC) alignment besides traditional rubbing technology. A strong relationship between relative humidity (RH) and the photoalignment quality of hydrophilic azobenzene dye brilliant yellow (BY) has been investigated. Good photoalignment quality can only be ensured at about 40% RH or below. On the other hand, the photostability of the alignment layer is also influenced dramatically by RH. The rewritability can be guaranteed at extremely low RH (<= 10%). It is gradually lost with increasing RH, and the alignment layer becomes photostable against further light exposure when at 40% RH or above. Therefore, the BY photoalignment layer can be tuned from rewritable to photostable by simply adjusting RH, and thus multistep photopatterned alignments can be obtained and reserved based on this method. Similar properties are also expected for other hydrophilic azobenzene photoalignment materials, where the specific RH values may vary correspondingly. The reason is due to the strong intermolecular interaction and J-aggregate formation of BY molecules with water insertion. Moreover, the lyotropic LC formed by J-aggregated BY molecules in aqueous solution is reported here.

Broadband quarter wave plates are widely used in optical system, especially in display system. Above all, a broadband quarter wave plate can be treated as an isolator in display to provide “perfect” dark state so as to improve the contrast ratio. A kind of broadband quarter wave plate combined by two waveplates with angle deviated is proposed and manufactured in this paper using coating technique. Two methods of combination of the two waveplate are proposed and tried. The reflection spectrum shows that this kind of structure can provide good dark state in display system.

Microlens arrays are introduced on glass substrates to improve the out-coupling efficiency of organic light-emitting devices (OLEDs). The microlenses suppress waveguiding loss in the substrate. A theoretical model, based on electromagnetic wave propagation and geometric ray tracing, is developed to simulate the enhancement effects and optimize the structure parameters of the lens pattern. A simple soft-lithography approach is employed to fabricate the microlens array on glass substrates. With the use of an optimized lens pattern, an increase of over 85\% in the coupling efficiency of the OLED is expected theoretically. An increase of 70\% in the coupling efficiency is achieved experimentally, without detrimental effect to the electrical performance of the OLED.