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We achieve high‐framerate (< 100 μs) high‐contrast‐ratio ferroelectric liquid crystal displays (FLCD) on Gen 4.5. Innovatively, a new polyimide (PI) that is suitable for ferroelectric liquid crystal (FLC) alignment is synthesized and tested on the production line. It replaces Nylon 6 (N6), which was the barrier to the commercialization of FLCD. Moreover, a new FLC is synthesized to match requirements in mass production. Additionally, various materials were studied to investigate the surface energy and relative performance. It is not only proof of the feasibility on the production line, but also a significant step towards the commercialization of field‐sequential‐color high‐resolution FLCDs. [ABSTRACT FROM AUTHOR]

We have developed a new polarizer system named "Light Control Polarizer (LCP)" that has a shading effect comparable to that of light control films (LCF) while significantly improving on‐axis luminance loss. The LCP exhibits a louver effect of 1.4% at a 60° polar angle and 1.1% at a ‐60° polar angle in vertical direction, with a 20% increase in on‐axis luminance over LCF and a 12% increase in contrast ratio (CR). These characteristics allow the LCP to work as an alternative to LCF providing with effective light shielding in the vertical direction without sacrificing display luminance. [ABSTRACT FROM AUTHOR]

We have achieved CR 3000:1 for 4K ADS products including MNT & TV, while balancing such specifications of GTG, transmittance, driving voltage, color gamut etc. In this article, systematic analysis have been conducted and conclusions on the influences between high CR and negative LC, RGB, PVX and high‐collimation BLU have been drawn. [ABSTRACT FROM AUTHOR]

A successful test of Ferroelectric Liquid Crystal Displays (FLCD) on Gen 4.5 is realized in this paper. A new polyimide (PI) that can replace Nylon 6 (N6) is synthesized and tested on the production line. This used to be the barrier in the commercialization of FLCD. Apart from that, a new FLC for mass production is synthesized. To investigate the surface energy and relative performance, various materials are compared. This proof of the feasibility on the production line is a significant step towards the commercialization of field‐sequential‐color high‐resolution FLCDs. [ABSTRACT FROM AUTHOR]

A new polarizer system has been developed to improve the light efficiency and on‐axis contrast of LCDs by reflecting and recycling oblique light. The new polarizer system realizes an 8% increase in on‐axis brightness and on‐axis contrast. [ABSTRACT FROM AUTHOR]

As the market for near‐eye display devices and other similar devices expands, these devices and their display performance are receiving more and more attention and challenges. Therefore, this paper reports a display module consisting of a high PPI fast LCD based on LTPS backplane paired with an ultra‐multi‐partition Mini‐LED backlight. The display adopts a new pixel structure and is able to achieve a transmission rate of 1.8% and a high contrast ratio of 500:1 on 1411 PPI. Besides, the multi‐partition Mini‐LED backlight unit is able to achieve 1728 partitions of local dimming and high dynamic contrast ratio of the display module, meanwhile the brightness of the backlight is increased by 4.9% with the same power consumption, making the overall display module brighter. [ABSTRACT FROM AUTHOR]

Brightening polymer-stabilized bistable cholesteric liquid crystal (PSBCLC) films with doped fluorescent dyes were prepared using the polymerization-induced phase separation (PIPS) method. The transmittance performance behavior of these films in both states (focal conic and planar) and absorbance change in multiple dye concentrations were studied using a UV/VIS/NIR spectrophotometer. The change occurring in dye dispersion morphology with different concentrations was obtained by means of the polarizing optical microscope. The maximum fluorescence intensity of different dye-doped PSBCLC films was measured using a fluorescence spectrophotometer. Moreover, the contrast ratios and driving voltages of these films were calculated and recorded to demonstrate film performance. Finally, the optimal concentration of dye-doped PSBCLC films with a high contrast ratio and a relatively low drive voltage was found. This is expected to have great potential applications in cholesteric liquid crystal reflective displays. [ABSTRACT FROM AUTHOR]

In this work, we prepared polymer-dispersed liquid crystal (PDLC) films with good mechanical properties, high contrast ratio (CR), and low driving voltage (Vdr). These PDLC films included two different monomers, which were hydroxyl methacrylate monomers and fluorinated methacrylate monomers. The electro-optical properties, micro-structures and mechanical properties of these films were also characterised. It was found that the hydroxyl methacrylate monomers could improve the adhesion force of the PDLC film, while fluorinated methacrylate monomers could reduce the driving voltage. In this way, the PDLC films with excellent comprehensive performance could be obtained. Compared with the original sample, the adhesion force was improved approximately 200% to 180 N/cm2. The driving voltage threshold was reduced about 140% to 18.5 V. The contrast ratio was increased about 150% to 51.9. This work enlightened a novel way to improve the mechanical properties of PDLC films and promised a broader application of PDLC. [ABSTRACT FROM AUTHOR]

Brightening polymer-stabilized bistable cholesteric liquid crystal (PSBCLC) films with doped fluorescent dyes were prepared using the polymerization-induced phase separation (PIPS) method. The transmittance performance behavior of these films in both states (focal conic and planar) and absorbance change in multiple dye concentrations were studied using a UV/VIS/NIR spectrophotometer. The change occurring in dye dispersion morphology with different concentrations was obtained by means of the polarizing optical microscope. The maximum fluorescence intensity of different dye-doped PSBCLC films was measured using a fluorescence spectrophotometer. Moreover, the contrast ratios and driving voltages of these films were calculated and recorded to demonstrate film performance. Finally, the optimal concentration of dye-doped PSBCLC films with a high contrast ratio and a relatively low drive voltage was found. This is expected to have great potential applications in cholesteric liquid crystal reflective displays.

Electrochromic (EC) materials that change color with voltage have been widely studied for use in dynamic windows. However, colorless-to-colorful switching with high contrast ratio is generically unattainable, especially for colorless-to-black electrochromic materials with an ultrahigh contrast ratio over the entire visible region. In this work, we developed Nb1.33C MXene-based dynamic windows with colorless-to-black switching of up to 75% reversible change in transmittance from 300 to 1,500 nm. By exploring the electrochromic effects of different electrolytes through in situ optical changes and electrochemical quartz crystal microbalance (EQCM), it is found that electrochromic behavior is greatly influenced by the extent of reversible Li+ insertion/deinsertion between the two-dimensional Nb1.33C MXene nanosheets. In addition, a colorless-to-black EC device based on Nb1.33C with an overall integrated contrast ratio over 80% was successfully constructed by a solution-processable spin coating method. This work enables a simple route to fabricate MXene-based high-performance electrochromic smart windows, which is important for further expanding the application of MXenes to optoelectronic and photonic applications. [ABSTRACT FROM AUTHOR]

In this paper, polymer-dispersed liquid crystal (PDLC) films were made from a mixture of prepolymer, liquid crystal and reticular nanofibre films by the polymerisation induced phase separation (PIPS) process. By comparing the microstructure and electro-optical curves of samples with the different liquid crystal content, it was proved that the cavity size of the polymer network has the obvious effect on the electro-optical properties of the PDLC films. Reticular nanofibre films were introduced into samples with different liquid crystal content, and the changes in the polymer network and electro-optical properties of these samples were analysed with SEM images and electro-optical curves. It is established that electro-optical properties and structural peculiarities of PDLC doped with reticular nanofibre films were improved. When the thickness of the embedded nanofibre films continues to increase, the electro-optical properties of the PDLC films can continue to improve. Therefore, the development of reticular nanofibre films doped PDLC films with faster fall time, better contrast ratio will significantly enhance the potential technological applications of PDLC-based devices for smart windows, sensors and flexible devices. [ABSTRACT FROM AUTHOR]

In this paper, in the mixed system of five kinds of acrylate polymeric monomers, nematic liquid crystals and reticular nanofiber films, the polymer dispersed liquid crystal (PDLC) films were prepared by the polymerization-induced phase separation method, and their properties were analyzed by combining the electro-optical curves and microstructure. The experimental results have proved that the cavity size of the polymer network can be controlled by adjusting the ratio of photo-polymeric monomers and the content of liquid crystal, thus directly affecting the electro-optical properties of PDLC films. This research will improve the potential technical applications of PDLC devices inflexible displays. [ABSTRACT FROM AUTHOR]

In the present paper, influence of the functionality of thiol monomers and acrylate crosslinkers, as well as crosslinker chain length on the polymer morphologies and electro-optical properties of the PDLC films, were systematically investigated. Results revealed that increasing the functionality of thiol monomers, both threshold voltage (Vth) and saturation voltage (Vsat) were increased due to the dense microstructures resulting from higher reactivity of thiol monomers. However, with increasing the functionality of acrylate monomers, Vth was increased evidently, but a relatively small rise of Vsat was found with moderate functionality monomer. Additionally, the increase in the chain length of flexible crosslinker resulted in an increase in the average size of LC droplets with a corresponding decrease in Vth and Vsat. On the whole, polymer morphology and electro-optical properties of the PDLC films can be artificially manipulated by adjusting the molecular structure of polymer matrix. A PDLC film exhibiting low driving voltage (24.0 V), moderately high contrast ratio (97.0) and fast response time (<8.0 ms), was found by employing the Pentaerythritol tetrakis (2-mercaptoacetate) (4SH), trimethylolpropane triacrylate (TMPTA) and polyethylene glycol diacrylate (PEGD 600). [ABSTRACT FROM AUTHOR]

A novel polarizer system that modifies only the bottom polarizer has been developed to reduce the off‐axis light leakage of LCDs. A 13‐inch prototype using the new polarizer system has successfully reduced off‐axis light leakage to 60% that of a conventional polarizer system. The new polarizer system is useful to weaken halo artifacts of HDR backlights. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We have developed an FFS‐based LCD that can be switched between two display modes: 1) wide view mode with high contrast ratio and 2) narrow view mode enabling privacy. By combining the new LCD configuration with Soft Veil View technology, our 5.3‐inch prototype has successfully enabled: 1) enhanced optical properties and 2) privacy mode with a larger off‐axis area that prevents unauthorized image viewing. [ABSTRACT FROM AUTHOR]

A kind of reflective mode LCD was reported years ago by professor Shin‐Tson Wu, called Mixed‐mode Twisted Nematic (MTX) LCD[1]. Based on MTN mode RLCD, we promoted the contrast ratio and reflectivity of RLCD by optimizing the cell structure and pixel design. Meanwhile, according to controlling the different optical layer axis directions and using new type materials, the contrast ratio and reflectivity are increased further. To improve the visibility of RLCD in a dark environment, we also developed the front light unit solution. [ABSTRACT FROM AUTHOR]

A chiral liquid crystal containing reverse mode PDLC (Ch‐R‐PDLC), which showed transparent state at 0V, was prepared. This Ch‐R‐PDLC achieved both low voltage driving and strong scattering simultaneously by optimizing the helical pitch length of the chiral liquid crystals and by using original mixtures of liquid crystals and monomers. Transmittance of the Ch‐R‐PDLC was 80% at 0V and 5% at 7V, which was comparable to the normal scattering type. This driving voltage was low enough to employ widely used drivers. A Ch‐R‐PDLC display that was bright in the ON state and highly transparent in the OFF state was also demonstrated. [ABSTRACT FROM AUTHOR]

A new design of 1‐to‐2 line all‐optical logic decoder has been proposed based on a two‐dimensional photonic crystal (PhC) structure. The decoder operates based on the principle of optical interference within the PhC waveguides. An optical bias has been used to generate high‐logic states at zero input conditions. Simulations explore a high contrast ratio, in the order of 11.3 dB, for both the output ports of the device. Response times have been calculated from the transient responses of the output ports, and are found as 0.65 and 0.77 ps for the ports 1 and 2, respectively. These results in a bit rate of ≃625 Gbps, considering the worst‐case scenario. Phase sensitivity analysis has also been performed which shows that the device output is quite sensitive to the differences in phases of the bias and signals. However, a strategy has been proposed to make the same insensitive to the phase changes. Finally, the small footprint (in the order of 234 μm2); standard operating wavelength; and silicon‐based design of the decoder, along with its said merits, make the device highly potential for on‐chip photonic‐integrated‐circuit applications. [ABSTRACT FROM AUTHOR]

We propose a high dynamic range (HDR) mini‐LED enhanced liquid crystal display (LCD) system. Through both numerical simulations and human visual perception experiments, we find that the halo effect (light leakage between adjacent black and bright pixels) can be suppressed to unnoticeable level by optimizing the LCD contrast ratio, number of local dimming zones, LED light expansion and local light confinement. The benefits and problems of each solution are discussed in detail. Additionally, with the merits of low power consumption, freeform panel shape and thin profile, mini‐LED backlit LCDs is emerging as a strong contender for next‐generation HDR displays. [ABSTRACT FROM AUTHOR]

'LCD vs. OLED: who wins?' is a heated debatable question. Each technology has its own pros and cons. We review recent advances in liquid crystal displays (LCDs) from three performance metrics: response time, contrast ratio, and viewing angle, which determine the final-perceived image quality. To enhance LCD performance, ultra-low viscosity materials, quantum dots, and new device structures have been explored, and their working mechanisms investigated. Another round of LCD innovation is around the corner. [ABSTRACT FROM AUTHOR]

In this work, we report on the photo-induced fluorescence switching film by using CH 3 NH 3 PbBr 3 perovskite nanoparticle fluorophore and spironaphthoxazine photochromic dye for the first time. Attributed to the effective spectral overlap between absorption of spironaphthoxazine in ring-opened merocyanine form and emission of CH 3 NH 3 PbBr 3 energy transfer-induced fluorescence switching film is demonstrated. In addition, both highly luminescent optical property of CH 3 NH 3 PbBr 3 and efficient photochromic reactivity of spironaphthoxazine, enabled high emission on/off emission contrast (>10.0) and fast emission turn on (4.0 s). Finally, modulation of the switching speed is successfully achieved by introducing the chelating agent into the photochrmic film, which effectively retards the rate of photochromic reaction of spironaphthoxazine. [ABSTRACT FROM AUTHOR]

In this paper, all-optical XOR and NAND logic gates based on gold disk-shaped nanoparticles have been proposed. The proposed structure consists of a non-periodic array of disk-shaped nanoparticles that are placed on SiO 2 substrate. The gates function is based on the constructive and destructive interferences between the input signals. For the NAND gate the phase difference between the input signals has been used to create a destructive interference. The most advantages of these structures are subwavelength dimensions and high contrast ratio of about 26 dB and 24 dB for the XOR and NAND logic gates, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We developed high contrast flexible blue phase LCD with polymer walls by UV irradiation through a photo mask. We clarified that both polymer walls and BP stabilization can be achieved by only one time UV irradiation and the polymer walls can suppress the distortion of the alignment of blue phase LC in a bending state. [ABSTRACT FROM AUTHOR]

In this work, an LCD mode with vertical alignment and in-plane switching electrodes (VA-IPS) is proposed to improve optical performance. This mode can control tilt angles of LC molecules via combinations of various distances of the in-plane-switching electrodes, and thus improve color washout. Also, a new driving scheme combining T-T type driving method with charge-shared (CS) structure is presented to further improve the picture quality at oblique viewing angle by not only adjusting spacing of in-plane-switching electrode pairs but also creating an extra voltage difference by CS structure in one pixel. After simulation and optimization, this mode possesses very small oblique gamma distortion and TRDI as low as 0.13. [ABSTRACT FROM AUTHOR]

A high-contrast, fast-response, and polarizer-free reflective display using a dye-doped dual-frequency liquid crystal gel is demonstrated. The high contrast ratio originates from the combination of light scattering from the microdomain polymer gel and absorption from the black dyes. The fast response is due to the frequency modulation of the dual-frequency liquid crystal. [ABSTRACT FROM PUBLISHER]

We examined the conditions that produce no grayscale inversion over a wide-viewing-angle. We also examined the optimum conditions for a retardation film that compensates for the retardation of all LC cells in the dark state. Using these conditions, we realized a wide-viewing-angle, high-contrast LCD with a simple structure and high brightness. [ABSTRACT FROM AUTHOR]

The current work aimed to fabricate polymer dispersed liquid crystal (PDLC) films using heterocyclic acrylate monomers containing oxygen atoms. The incorporation of oxygen heterocycles into the host polymer matrix significantly improved the electro-optical properties of PDLC films. Particularly, the high contrast ratio 330.0 was realized for the monomer Trimethylolpropane formal acrylate (TFA). Further, the excellent electro-optical properties, including low driving voltage (10.0 V), moderately high contrast ratio (64.0) and short response time (<8.0 ms) were obtained when the liquid crystals/polymer composite film thickness decreased from 20 μm to 8 μm. This work has provided a novel materials system to promote the application of PDLC films in the thin-layer liquid crystal display. [ABSTRACT FROM AUTHOR]

We present the development of an ultrafast two-dimensional (288 × 132 elements) reflection modulator array based on GaAs-AlGaAs multiple quantum-wells embedded in an asymmetric Fabry-Perot structure. The array has low operation voltage (< 4 V), low insertion loss, and high contrast ratio at ∼846 nm. This array was hybridized to 0.25 μm complementary metal-oxide-semiconductor driver providing 256 gray levels resolution at frame rate of 50 kHz (driver limited). Major progress in reducing the severe nonuniformity problem of the cavity resonance wavelength in such devices to less than 3.4 nm variation across a 4-in wafer was achieved. [ABSTRACT FROM PUBLISHER]

This paper proposes a novel approach for low cost fabrication of large area wire grid polarizer (WGP). WGPs regarded as one potential alternative to traditional rear polarizer and DBEF possess the advantages of large contrast ratio (CR), high transmission. To date WGPs can be fabricated through electron beam direct write, which is slow and expensive, therefore not suitable for large area application. With the development of nano‐fabrication methods, for instance, nanoimprint lithography (NIL), large area WGP can be made at low cost and fast speed. Furthermore, flexible polarizer can also be made through roll‐to‐roll (R2R) NIL. In this paper, a WGP with high TM transmission of around 85% and low TE transmission down to 0.2% through the visible light spectra will be realized through nanofabrication. The contrast ratio of the WGP can reach >450 with peak value >3000. For the fabrication process, atom layer deposition (ALD) will be utilized to prepare imprint mask which can achieve highly precise control of expected structure. In this paper, characterization of the designed WGP will also be narrated in the back part, including transmission, CR and the SEM schematic diagram. We believe that low cost fabrication method shows the potential to be adopted for industrial fabrication of polarizer in the future. [ABSTRACT FROM AUTHOR]