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We present a feasible modeling method to estimate the proper curvature for large-sized curved TVs. We especially focused on two factors – preference and perceived distortion – to be considered to determine the proper curvature. The preference includes a number of advantages that people expect to fulfill the possibilities of a more immersive image and sense of realism from curved display. On the other hand, the perceived distortion means the side effects that people can notice uncomfortable feeling caused by the shape of a curved one. In order to find out how two factors would be different as a number of conditions like curvature, size, and viewing angle change, a series of subjective assessments were conducted. The evaluation results show that both the preference and perceived distortion vary with the conditions considerably. We performed the statistical analysis based on the results and proposed the quantification model of proper curvature, which has higher preference and less perceived distortion, for various-sized curved TVs.

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.

The focus of this paper is to evaluate the ability to reproduce preferred colors for mobile displays under ambient illumination condition. Mobile liquid crystal display (LCD) and active matrix organic light emitting diode (AMOLED) are used and 3D gamut volume in CIECAM02 QMh space is utilized to take absolute perceptual attributes into account. The ‘degree of inclusion (DOI)’ is calculated from the quantity of colors included within display gamut volume among the preferred colors of 1260 from six categories of image database. As a result of this evaluation, the ability of LCD to reproduce preferred colors is similar with a level of AMOLED due to its high brightness under general office environment.

A series of psychophysical experiments using categorical judgment method was carried out to develop a colour naturalness metric (CNM) for evaluating image quality of mobile displays. These experiments included colour naturalness judgment and image-quality difference judgment. Through the former one, CNMs were trained and the latter experiment tested the metrics. Two types of CNMs were newly proposed: nonlinearly decaying CNM and linearly decaying CNM. In the CNMs, it was assumed that one familiar object in an image played a critical role to judge the colour naturalness of the whole image. Through a performance comparison between objects' models, one critical object in a scene was selected and with the critical object's model, the whole scene's colour naturalness was predicted.

A series of psychophysical experiments using paired comparison method was performed to investigate various visual attribute affecting image quality of a mobile display. An image quality difference model was developed to show high correlation with visual results. The result showed that Naturalness and Clearness are the most significant attributes among the perceptions. A colour quality difference model based on image statistics was also constructed and it was found colour difference and colour naturalness are important attributes for predicting image colour quality difference.

We present a feasible modeling method to estimate proper curvature for large-sized curved TVs. The proposed method was derived from subjective quality assessment and statistical analysis. This model can be used to design large-sized curved TVs that can offer higher preference and less perceived distortion.

An adaptive image-quality model that incorporates the ambient illumination conditions were developed by carrying out a series of psychophysical experiment for assessing the image quality under dark, bright and outdoor bright surround conditions. Two objective measures (colour-difference metric and colour-naturalness metric) were employed to predict image quality.