Comparison of Readability and Sharpness of Different Professional Displays

Professional displays must fulfill demanding specifications like readability in ambient light and sharpness of text. This is somewhat contractionary as anti-glare (AG) films are good for reflection reduction but reduce sharpness. We present measurements in dark room using a spotlight and large flat light source (both WLED) and an imaging light measurement device. The set-up is in specular geometry adapted from ISO 15008. The spotlight represents for example office lights and sun. Reflections from e.g., shirts, walls, windows, and sky are simulated by a flat lamp. The ambient light performance was rated by the reflectance characteristics (specular, haze, diffuse). The sharpness was measured using a macro lens via luminance profiles of neighboring pixels and the modulation transfer function (MTF). The results of four professional monitors for a safety-critical application in well light offices including an expert evaluation are: Anti-reflection (AR) has the highest sharpness, but it’s sharp contours of reflections are annoying. AG-only displays results in a relative high reflectance and low sharpness. The combination of AR with moderate AG is the best, but most expensive solution.