Abstract
High-resolution LCD screens can depict realistic scenes, but even under restricted viewing conditions (e.g., monocular, stationary) we can usually tell that the surfaces and objects shown are not real. One reason may be that we can tell that the screen emits light instead of simply reflecting incident light. Here we investigated what cues allow observers to determine that a small patch of an LCD screen is light-emitting rather than reflective. We cut a 3 x 3 grid of nine 3.2 cm square apertures in each of 27 black cardboard panels. Behind eight randomly selected apertures on each board we attached patches of gray and off-gray (e.g., beige) paper; we left the ninth aperture empty. The paper patches were picked randomly from twelve samples. On each trial we put a board in front of a light-emitting LCD screen, and the observer judged which aperture contained the screen. In the luminance-match and colour-match conditions, the screen showed a gray region whose luminance or colour (i.e., CIE XYZ coordinates), respectively, were matched to a randomly chosen paper patch. In the texture-match condition the screen showed a colour-calibrated photograph of a randomly chosen paper patch. The three 108-trial conditions were randomly interleaved. All observers (n=5) were well above chance performance in the luminance-match condition (95% correct), two were above chance in the color-match condition (16% correct), and three were above chance in the texture-match condition (30% correct). We conclude that color is an important cue for glow detection, but not the only relevant cue. Further work will explore the role of cast shadows and texture-based lighting direction cues in making LCD screens discriminable from reflective surfaces.
Meeting abstract presented at VSS 2017