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Ultra-high definition (UHD) curved organic light-emitting diode (OLED) TV requires advanced technologies to realize mass production. White, red, green, and blue (WRGB) OLED TV based on stripe WRGB sub-pixel structure has distinct advantages in luminance of white, faster response time, wider viewing angle, and potential higher resolution. In this paper, we will introduce technological progress for commercializing large-sized and UHD curved OLED TV. Those technologies including oxide thin film transistors, white OLEDs, compensation circuit, and solid phase encapsulation enable panel size scalability as well as mass production with lifetime reliability.

Large-sized OLED displays require advanced technologies to realize mass production. The competitiveness of OLED TV comes from the combination of oxide TFT and WRGB OLED technology. Those technologies including image quality of OLED TV, oxide TFT, WOLEDs, and solid phase encapsulation enable panel size scalability as well as mass production with lifetime reliability. We will introduce technological progress for commercializing large-sized OLED TV.

WRGB OLED displays have more extra sub-pixels to improve image quality than RGB OLED displays. This paper presents advantages of WRGB sub-pixel structure in OLED displays by novel sharpening method which makes an image much sharper with less ringing artifacts. As a visual experimental result, the edges of images could be represented sharper and sharpening artifact was also reduced. In conclusion, the structure of WRGB sub-pixel structure has advantages to enhance image quality.

A transparent organic light emitting diode (OLED) display has received much attention as one of the future display technologies. While various studies have conducted to increase transparency, reduce haziness and remove image distortion in transparent OLED, fewer studies have attempted to provide the requirements of visual quality for a particular purpose of applications. In order to establish the guidelines of visual quality requirement, a method for the visualisation of seeing through a transparent OLED is required. In this paper, we present a feasible simulation method for visualising transparent OLED. We focused on three influential conditions—illumination, transparency and contrast—though numbers of conditions affect visual quality in Transparent OLED. And each condition was implemented on the assumption that the design of pixel structure may be separated into two parts, emitting and see-through areas. All of the procedures were derived from image processing techniques. Consequentially, a simulation result can be seen as one image, which is composite of two images, image on the display and image through the display. The simulation results provide an intuitive approach to examine the visual quality. We believe that the proposed method can be used to give guidelines for designing transparent OLED.

Recently, the gamma subcommittee of the International Committee for Display Metrology has adopted various gamma measurement methods in Information Display Measurements Standard. This article describes further tests including perceptual verification of the suggested measurement methods. In order to verify the suggested measurement method, visual assessment has been carried out. The results of visual assessment can be applied to provide gamma distortion threshold values of the suggested metrology in Information Display Measurements Standard.

The temporal transmittance of a liquid crystal (LC) cell shutter was investigated for various incident angles to verify the possibility of a fast switching time. For a mono-domain vertical alignment (VA) cell, the switch OFF time in which the LC restores to its initial alignment state under no driving voltage is found to relate to the angle of the incident light. A decrease of switch OFF time is observed when the azimuth angle of the incident light approaches the azimuth angle of the LC optical axis. For a 4-domain VA cell, switch OFF time is observed not to decrease for any obliquely incident angle.

Three-dimensional (3D) display devices provide a more realistic experience of entertainment. A great deal of research has been doing to enhance 3D image quality and reduce visual fatigue of stereoscopic display. One of the important considering factors of 3D research is the disparity which is, in general, defined the positional difference between left and right images. The definition is, however, too ambiguous to fix the disparity from various 3D contents. A new definition and a classification method, therefore, are suggested in this study. Furthermore, the validity of the suggested method was verified from a visual assessment.

This paper presents outdoor image quality enhancement methods based on adjusting gamma shape and chroma compensation for mobile display. In order to verify the suggested method, a psychophysical experiment was performed using 22 test images that are categorised by colour attributes and contents. The test images that are applied both methods are more preferred than others with statistical significant difference.

Blue primary's materials of three-primary color display have been hot issues in display industry because the blue materials of LED or OLED generally have shorter lifetime than red and green materials. Thus the choices of blue materials are very limited when applying them to displays. This paper, to overcome the limitation on selecting blue color materials, we suggest visually acceptable color ranges of blue primary when compared to the blue color of Rec. 709.

Image sticking and lifetime issues have been hot topics throughout the history of display devices. This paper describes the effect of the usage of contents to evaluate image sticking of display devices. Two different experiments were carried out to find the usage effect for different application such as mobile and TV using OLED products. The results show that the image sticking can be occurred in different time when different contents are applied to each display devices.

Liquid crystal(LC) materials with 1,3,2-dioxaborinane group have been synthesized and their physical properties have been investigated to get new LC mixtures. The test LC samples were made up of a base LC material doped with 5, 10, 15, 20, and 25% of each compound in weight. We have measured optical and dielectric anisotropy, nematic-isotropic phase transition temperature, and threshold voltages as a function of doping concentration. From our measurements, it is found that each compound has different properties compared with other ones. So, these results would contribute to development of new LC mixtures for LCD applications.

A set of new, blended nematic liquid crystal mixtures to improve the performance of highly multiplexed TN-displays are presented. The physical and electro-optical properties of new LC mixtures have been investigated, along with the frequency and temperature dependence of threshold voltage about newly developed liquid crystals. The multiplexable mixtures are completely miscible and can be blended, thus leading to new mixtures covering a wide range of threshold voltages 1.2 > V10 > 2.0 V, nematic-isotropic phase transition temperatures 60 > Tc > 100[ddot]C, and/or optical anisotropies 0.13>Δ n>0.18.

We have studied the chirality effect on the optical nonlinearity of ferroelectric liquid crystals (FLCs) by means of the second-harmonic generation (SHG). A chiral agent of CB15 is added to a commercial FLC of CS1017 for controlling the optical activity in terms of chirality. From the electric-field dependence of the SHG profiles, it is found that the chirality contributes to both the second-order nonlinearity and third-order one which couples with a static electric field.

The enhancement mechanism for the second harmonic generation (SHG) of chromophores in chiral smectic liquid crystal environment has been studied. The liquid crystals (LCs) studied are SCE13 and its racemic version, SCE13R (British Drug House), the former of which has the chiral and the latter nonchiral smectic C phases at room temperature, respectively. The LCs are doped with 4-dimethylamino-4′-nitro stilbenes (DANS) molecules in weight. It is found that the SHG intensity is enhanced by the doping of the DANS molecules.

The poling process in nonlinear optical (NLO) polymer films is studied by the second harmonic generation (SHG) and optical retardation measurements. The PMSt polymer is used as a NLO chromophore whose dipole moment is aligned transverse to the main-chain backbone. Both the optical retardation and the SHG intensity increase during poling process and decay after poling in the same fashion. The optical retardation is found to be more sensitive to the thermal fluctuations than the SHG.

We have studied the electric field-controlled optical nonlinearity in a homogeneously aligned ferroelectric liquid crystal (FLC), SCE 13, for understanding the second harmonic generation (SHG) process at a molecular level. From the SHG intensity profiles, measured as a function of the azimuthal angle for rotation at an oblique incidence, all the relevant nonlinear optical (NLO) coefficients are determined self-consistently. It is found that the field dependence of the NLO coefficients can be described in terms of the third-order nonlinearity which couples linearly with a static electric field. The magnitude of the third-order NLO coefficient is of the order of 104 pm2/V2, which is consistent with the measured value for a racemic version SCE 13R.

The polar order coupling effect in a ferroelectric liquid crystal (FLC) composite doped with nonlinear optical molecules has been studied by means of the second harmonic generation (SHG). The FLC composite is made up of a ferroelectric liquid crystal, SCE 13, doped with 5% of 4-dimethylamino-4′-nitro stilbenes (DANS) in weight. It is found that the SHG intensity from the doped DANS molecules is greatly enhanced by the polar order present in the FLC environment. Moreover, a delicate interplay between the orientational coupling and the polar one determines the molecular orientation of DANS with respect to the molecular director of the FLC.

We have developed a new experimental method of measuring the second harmonic generation (SHG) from ferroelectric liquid crystals (FLCs). The measurements are made on a homogeneously aligned FLC cell at an oblique incidence to the surface normal as a function of the azimuthal angle of rotation. This method is simple and powerful to study both the molecular orientation and the associated nonlinear optical (NLO) properties of FLCs. The absolute values of the NLO coefficients are determined self-consistently from both the SHG intensity profiles and the Maker fringes obtained for the same FLC cell. The anomaly observed in the electric field dependence is described in terms of the third-order optical nonlinearity of FLCs.

The relaxation dynamics of nonlinear optical chromophores in photo-polymer composites is studied for a basic understanding of the poling mechanism. The composite films are made up of a photo-polymer containing 0.5 % by weight of 4-dimethylamino-4′-nitrostilbene. They are poled under an external dc electric field at room temperature, followed by UV curing. It is found that for such composite films both the optical retardation and the second harmonic generation (SHG) intensity clearly decay as similar stretched-exponentials in time, and their relaxation behavior is predominantly governed by the period for UV curing. It is suggested that the optical retardation involves mostly the axial order while the SHG intensity is strongly correlated to the degree of polar ordering of the chromophores.

— Various gamma-evaluation methods are investigated and newly suggested in order to establish a standard gamma metrology. First, test patterns are suggested and compared for display technologies that dynamically adjust gray levels such as global-dimming LCDs and PDPs. Second, two gamma-determination methods are compared and their accuracy determination methods are suggested. Third, two new models for gamma-distortion phenomena are suggested. Finally, the monotonic characteristics of EOTF are investigated. For the most part of this study, a new international standard named ICDM-DMS is suggested.

— The cause of the angular dependence of 3-D technology that requires the use of eyeglasses with linear or circular polarization is analyzed. For 3-D technology that requires the use of eyeglasses, anisotropic media such as a polarizer or retardation film determines the polarization state. Therefore, the angular behavior of 3-D display performance is also affected by the characteristics of the anisotropic media that have intrinsic angular dependence. Various conditions of the optic axes of the imaging display and eyeglasses are investigated to understand their effect on 3-D display performance. The result shows that some conditions of the optic axes can cause non-negligible degradation of 3-D display performance.

— The luminance distribution of autostereoscopic 3-D displays using the parallax-barrier method was simulated by two different calculation methods. The first method directly calculates the total luminance distribution by summing light rays coming from different positions on the imaging display through a parallax barrier at each eye position. The second method first calculates the angular distribution of light rays coming from the imaging display through a parallax barrier and then derives the spatial luminance distribution for each eye position. The two methods resulted in an equivalent distribution. Yet, the second method outperforms the first method in terms of calculating the speed and versatility.

— The dynamic performance of displays is an important characteristic for multimedia applications. Motion-picture response time (MPRT) has been used as an indicator of the dynamic performance of LCDs. This paper describes a comprehensive method of MPRT evaluation for the oblique viewing direction. By using a tilted camera configuration, the angular dependency of MPRT is investigated for the condition that the horizontally scrolling patterns are observed from the vertical direction. For each gray-to-gray transition, distinct changes in MPRT and the luminance profile of blur are observed.

— Image deformation caused by an outside force is observed to remain for hours at high gray levels for liquid-crystal displays (LCDs) in the multi-domain (MD) vertical-alignment (VA) mode. This so-called moving-image-sticking phenomenon demonstrated a non-symmetric luminance profile for the left and right viewing direction for MDVA-mode LCDs which have original symmetric viewing-angle characteristics. The generation of a stable reverse-tilt domain by an outside force was assumed to be the cause of this phenomenon, and the stability of a reverse-tilt domain under an electric fringe field was calculated by changing the electric-fringe-field distribution which determines the LC tilt direction. The domain of a given tilt direction is calculated to change to other tilt direction induced by a fringe field at a low gray condition, but to remain unchanged at a high gray condition. This agrees with the observed trends of duration time of the moving-image-sticking phenomenon.

The motion picture response time (MPRT) methods have been widely used to evaluate the degree of motion blurs in display devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs). Recently, APDC (Advanced PDP development center Corporation) announced the moving picture resolution method to represent the moving image quality of FPDs by using a resolving power as a measure. However, there are some differences in evaluation results of these two methods for same display devices. In this study, we measured the moving picture resolutions of five different FPDs which have different MPRT values and compared these results with actually perceived moving image qualities. The results show that the MPRT has higher correlation with actually perceived moving image qualities than the moving picture resolution method.

— The optical response time of liquid-crystal displays (LCDs) has recently been observed to be dependent on the viewing direction. For the vertically aligned LC mode, response time increased as the viewing angle increased when the final state is the zero gray level of the minimum luminance. This change in response time is analyzed to relate to the deformation of the normalized luminance curve of LCDs for different viewing directions. The dependency trends of the optical response time for the oblique direction can be estimated from the temporal luminance measurement data along the normal direction and the normalized luminance curve for oblique viewing directions.