Session Index

In this study, various polymer-dispersed liquid crystal (PDLC) cells were fabricated by illuminating with ultraviolet (UV) light to carry out the photopolymerization process. The effect of UV conditions on optical and dielectric properties of PDLCs are investigated and the optimized UV exposure time determined by means of dielectric spectroscopy.

 

We demonstrate that well-aligned uniform lying helix (ULH) can be generated by applying voltages during the isotropic-to-cholesteric phase transition to planar-aligned cholesteric liquid crystal cells with appropriate rubbing angles (α). The angle between the rubbing direction (ϕ) and the helical axis of ULH satisfies the condition of ϕ = α/2.

 

We demonstrated a high efficiency green organic light-emitting diode (OLED) with ambipolar host doped with thermally activated delayed fluorescence green emitter, achieving current efficiency of 90.25 cd/A, and external quantum efficiency of 25.01%.

 

In this study, a liquid crystal lens array (LCLA) used to fabricate photopolymer holographic optical element (HOE) is demonstrated. Due to the LCLA with tunable focuses, the fabricated HOE lens array achieves optical characteristics of multi-focuses to be used in the integral imaging system with larger viewing depth.

 

We use the new achiral bent-core liquid crystal compound doped with a chiral
additive to form blue phase liquid crystal. The phase sequence as examined by dielectric
spectroscopy and optical textures indicate that this LC material reveals wide temperature
range of blue phase.

 

A hydrogenated amorphous silicon (a-Si:H) thin-film transistor (TFT) gate driver with Vth shift compensation for high reliability 14.1-inch automotive display has been proposed. For using Vth shift compensation structure, degradation at normal and high temperature environment of driving TFT and noise-free block could be compensated.

 

The uniformities of the uniform lying helix (ULH) structures in cholesteric liquid crystal cells with various pretilt angles were investigated. The pretilt angle was controlled by varying the concentration of an agent for vertical alignment mixed with a planar alignment counterpart. A critical pretilt-angle condition exists to favor the ULH.

 

Reflectance tuning of the photonic bandgap (PBG) in a thin polymer-stabilized cholesteric liquid crystal (PSCLC) cell is observed. This mechanism is associated with DC field-induced displacement of the polymer network, enabling pitch-gradient structure in PSCLCs. This causes insufficient thickness for each pitch-length and thus decreases the reflectance of BPG.

 

The torques acting on liquid crystals molecules contain ion transmit, dielectric and electrically-conductive anisotropy of LCs of ion-doped LC cell with electric field causes the periodic alignment of the LCs. When the applied voltage is large enough to break the periodic alignment of the LCs, the scattering state occurs.

 

In this work, we successfully use nickel to form Schottky diodes with amorphous indium-gallium-zinc-oxide (a-IGZO). The rectification ratio, barrier height, ideality factor and breakdown voltage of the optimized diode with an 80-nm-thick a-IGZO layer are 2.86 × 10^4 at ± 1V, 0.679 eV, 1.263 and -5.8 V, respectively.

 

A pixel circuit with 2T1C structure and external threshold voltage compensation circuit shared by whole column is proposed for ultra-high-definition (UHD) AMOLED displays. The simulation results demonstrate the effectiveness of the VTH compensation, and the relative OLED current error rate is merely 1.82 % as VTH varies ±0.5 V.

 

A proposed two liquid crystal layer lens with electrically controllable bifocal is demonstrated to improve viewing depth in augmented reality. The optimal liquid crystal lens shows the minimum wavefront error close to 0.25 λrms and multi-focal planes to enhance viewing depth.

 

The purpose of this study is to induce the smectic-A (SmA) phase in a dual-frequency liquid crystal by doping with chiral molecules S811. Both the planar and the homeotropic textures are stable states in SmA phase and they can directly and reversibly be switched by modulating the voltage frequency.

 

The panels yellowing and transmittance were improved by optimizing SiNx films. The clearer SiNx film was introduced into OLED TFE (Thin Film Encapsulation) structure, as a result, the panel got higher transmittance and lower b* value.

 

A simple alignment method is proposed to fabricate the vertically aligned (VA) liquid crystal (LC) cells. This paper demonstrates that the new vertically aligned method not only avoids the complicated process, but also exhibits superior electro-optical characteristics compared with the conventional PI alignment.

 

With a horizontal electric field, the monomer exposed to UV light formed a polymer to stabilize a HAN (hybrid aligned nematic) structure, which has two-domain liquid crystal alignment. The device shows the symmetrical viewing angle and exhibits different viewing angles and electro-optical characteristics with various electric fields.

 

We use several methods to measure optical path length and electric-field-induced birefringence of the blue phase liquid crystal cell. Compared to Zeeman lasers, J. T. Ho set up[2], and interference spectrum, the optical path variation of the interference method is different. We modify the measured result by an adjustment parameter.

 

We successfully demonstrate a facile way for borylated compounds to deliver strong sky-blue and green TADF emissions. The peak efficiency of sky blue-emitting device with m-DMAC-B reached 14.3%(32.8 cd/A, 34.0 lm/W) while the green-emitting device with m-PXZ-B gave the peak efficiency of 14.0%(43.5 cd/A, 39.0 lm/W).

 

In this paper, subwavelength high-index-contrast gratings in the visible spectrum were proposed to produce directional and power-efficient stereoscopic effects. With the consideration of color dispersion, the threshold FWHM of directional backlight at 7 degrees which create viewing distance ranging up to 15 cm meets cross-talk criterion was evaluated