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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.

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.

— 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.