25.3: Observations of Luminance, Contrast and Amplitude Resolution of Displays

Abstract

contrast ratio and amplitude resolution are rapidly growing display specifications. Through a series of human factor studies we have developed simple guidelines for these specifications including viewer preference for luminance, optimal contrast ratio and amplitude resolution under realistic conditions. 1. Introduction past, conventional displays have been largely limited to a dynamic range similar to paper under office lighting conditions - approximately two or three orders of magnitude starting at a grayish black and finishing in the hundreds of cd/m 2 . This paradigm of hundreds-to-one contrast ratio, limited luminance and an amplitude resolution in the hundreds of steps is shifting today. Novel display technologies are emerging with the potential of much higher contrast and brightness. Moreover, even existing display technology is being pushed to the limit with a strong increase in display performance. This trend proceeds unevenly with contrast ratio rising faster than luminance, and amplitude resolution remaining largely static. As a result, many display designs make sub-optimal use of the device capabilities. This paper presents a series of human factor studies that aim to provide a basic framework of luminance, contrast ratio and amplitude resolution and their interaction. The use of a High Dynamic Range (HDR) display (1) as the imaging tool for the study, allows a large enough range for each variable to encompass all current and most near-future display technologies. The results of the study can be used to make design decisions for future displays as well as more realistic comparisons of existing devices. 2. Background Video Electronics Standards Association (VESA) and International Organization for Standardization (ISO) provide common guidelines for display specification including luminance and contrast ratio. Peak luminance is generally easy to measure and reported relatively accurately by the industry. Contrast ratio is significantly more challenging. A proper contrast ratio