Luminance binocular disparity for 3D surface simulation

Different stereoscopic effects, based on 100% binocular luminance contrast have been described previously (O'Shea & Blake, 1987; Howard, 1995): the "sieve" effect, the "binocular lustre" effect, the "floating" effect and the "rivaldepth" effect. By mean of a dichoptic set-up, we have measured the detection thresholds for these different effects in function of binocular luminance contrast. Psychometric data have been recorded using a Yes-No paradigm, a spatial 2AFC paradigm and a temporal 2AFC paradigm. Our results show that even for small contrasts all these stereoscopic effects are perceived. We have noticed an increase of the detection thresholds in the following order: "sieve", "binocular lustre", "rivaldepth" and "floating" effect. Two groups have been distinguished: Group 1: "sieve" and "binocular lustre" effects, processed by mechanisms based on summation and binocular rivalry; Group 2: "floating" and "rivaldepth" effects, processed, by fusional vergence, in addition to these mechanisms. These results brought up the question of the existence of luminance disparity detectors and of their relations with spatial disparity detectors. Some of these effects are present during the observation of metallic coatings. These surface simulation data will be used for metallic paint characterization and rendering, using Renault's real time Virtual Presentation of vehicles tool.