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Fractography is one of the methods to identify the condition that fracture occurred on brittle material, such as glass. There are several geometric characteristics on fracture surface, including mirror, mist, hackle, wallner lines, etc. to help to observe where the origin is and how much stress it suffered when broken. This study uses four-point bending test to obtain the fracture stress on test specimens and performs fractographic analysis to find out the mirror constant on glass substrates in different manufacturing processes. This article makes the clues to track if the glass was broken, whereas provides the hints to improve the glass strength in further steps.

Two new deep-blue dopants BD1 and BD2 with a wide singlet energy gap about 2.8eV were designed and developed and their electroluminescent devices exhibited saturated color with CIEy=0.05-0.09 with an EQE of about 4%, with a low driving voltage 4.24V. BD2 doped devices showed a longer lifetime stability of (T70) 2934h at an initial luminance of 500 nits, with a deep-blue emission having a CIE y~0.073.

In this paper, we discuss the light leakage issue of LCD panel occurred due to sharp temperature gradient and non-uniform stress distribution. By using numerical analysis and experiments, the relationship between light leakage and temperature gradient has been discovered. Thermal and stress simulations are applied in the analysis of light leakage phenomenon. Besides, we use simulation tools to predict the effectiveness of solutions for reducing the temperature gradient and stress distribution of LCD glass substrates. Finally, light leakage has been improved by using the rear frame with high thermal conductivity to reduce the temperature gradient and stress of the LCD panel.

Mura is an appearance that indicates low contrast and nonuniform brightness in thin-film transistor liquid- crystal display (TFT-LCD) devices. It is kinds of optical defects, such as ripple, smear, Newton's rings and moire, etc. This article primarily discusses ripple of optical films by using both experimental and numerical model to help understand how ripple occurs and why ripple seen by inspectors. After performing numerical analysis, we discover the root cause that induces ripple and realize why luminance on film-wrinkled area is varied, finally conclude the parameters that control physical phenomenon.

Incorporation of dibenzothiophene units into emissive materials (CH1) increased the charge carrier mobility in the order of 10−3 cm2 V−1s−1. Mixing the hole-rich CH1 with electron transporting PH3 in the emissive layers in appropriate proportions enhanced efficiency, lowered the driving voltage and prolonged the lifetime of the green and red phosphorescent OLED devices. Green phosphorescent OLED achieved an efficiency of 44.6 lm/W at a driving voltage of 3.67V and exhibited a lifetime of 115Kh (T50) at an initial luminance of 1000 nits.

We have developed new phosphorescent hosts having an electron transporting triazine molecular skeleton connected to hole transporting carbazolyl moieties, designed in order to attain high thermal stability, triplet energy sufficiently high enough to be compatible with phosphorescent green dopants. Green phosphorescent OLEDs using PH2 and PH3 achieved longer lifetime (T80 = 37h, 22h at L0 of 10000nits), seven fold increase in power efficiency at low driving voltage (∼ 4V) compared to CBP, with 17% external quantum efficiency.

The four-point bending test, pure bending, is one kind of common test to evaluate LCD panel strength. From lots of four-point bending experiments, we conclude that LCD panel strength is strongly correlated with manufacturing process. Also, St Venant flexure theory could not have properly analytical result to explain physical defect symptom of LCD panel after bending tests. This article aims at finding a numerical model to align both numerical and experimental results and obtains fracture stress under stabilized manufacturing condition.

3D display technology has been widely applied in many fields, such as entertainment, education. And also, there is being commercialized recently. Thanks for overdrive technology and multirefresh rate technology, it makes shuttertype glasses 3D stereoscopic technology could be realized in TFT-LCD display after CRT. The advantage of Shuttertype 3D stereoscopic is no limitation of viewing angle and distance compared to auto stereoscopic display such as barrier type and lenticular type ones. Owing to the different principle of various 3D stereoscopic technologies, 3D image quality measurement should depend on different 3D principle. Therefore, there are still many metrology related to 3D display that need to be defined clearly, especially for crosstalk. Here, we propose a method modified from different from that usually used in nakedeye and glasstype 3D stereoscopic display, an evaluation is suit for shuttertype 3D stereoscopic display.

When the CCFL is jumped outside the restricting lamp supporter during mechanical reliability test, the possibility of lamp failure is rapidly increasing in the LCD TV module. To prevent these failure symptoms at design phase, a modified Euler beam formulation is used to evaluate the risk of CCFL damage. This formula provides a readily way for realizing the structural reliability of CCFL in different supporter positions.

Mura defect induced by chip-on-glass packaging in 13-inch LCD-TFT was investigated using contour measurement and numerical analysis. Excellent correlation between Mura defect and localized warpage/principal stress has been established. Besides, the effects of ACF bonding temperatures and Si chip arrangement on Mura defect were studied and discussed.

In this paper, we discuss the light leakage phenomenon at the corners of LCD panel. Light leakage of LCD module occurs due to temperature gradient on the panel. Thermal stress caused by temperature gradient results in the light leakage. By using numerical analysis, we can calculate the distribution of thermal stress. The field of shear stress could be used to evaluate the magnitude of the light leakage phenomenon.

In this paper, the acoustic noise issue of LCD Module equipped with burst-mode inverter is discussed. By experiment, it is validated that the acoustic noise of LCD Module is emitted from lamp assembly in BLU (Backlight Unit). Theoretical analysis and simulations are thus performed to analyze the mechanism responsible for the acoustic noise of the LCD module. Besides, the experiments are made to verify the results of theoretically physical model. By the understandings of the formation of the acoustic noise, it is confident that the acoustic noise is doomed to be eliminated.

In this paper, we discuss the junction temperature of LED in the LCD module. The lifetime of LED strongly depends on the junction temperature. Besides, the optical performance of LED will decay with the rise of junction temperature. Mura of LCD module may occur due to non-uniform decay of the LEDs, which are the light sources of LCD module. Besides forward current and voltage, package material, PCB and LCD module design will also affect the LED junction temperature. By using numerical analysis, we can understand the parameters that strongly affect the LED junction and improve the quality of LCD with LED backlight. Lead frame material of LED package, dielectric layer of the PCB, and the back cover of LCD module are discussed in this paper to have a good thermal performance of the LCD module with LED backlight.

A numerical model has been developed to improve the quality of LCD module. By performing CFD analysis, heat transfer behavior for LCD module had been clarified. Designer can solve the issue of heat concentration produced by the electrodes of L shape CCFL to avoid the liquefaction of liquid crystal and the failure of compensation film. Experimental data is used to compare with simulation results and have a consistency in temperature distribution. The developed model has been used to predict the temperature distribution and evaluate the effects of different designs.