STEREO VIEWING OF LENTICULAR FOIL DISPLAYS: A GEOMETRIC ANALYSIS
O. Waelder, M.F. Buchroithner
In recent years the lenticular foil display (LFD) technology has been gaining increasing importance for the true 3D visualisation of geodata. Despite the fact, that this glasses-free auto-stereoscopic approach is by far not new, there still existed a certain vacuum in the actual understanding of its functioning, as far as both the psychological and physiological depth-cues are concerned. In particular, the latter ones have been investigated within a recent study carried out by the authors. It turned out that, in fact, when viewing an LFD, only very view of the respective stereo-laces of the totality of the interlaced stereomates are observed by the viewer. Actually, the human perception system is cheated, making use of the saccadic eye-movement. The observer screens ("scans") an LFD perpendicular to the strike direction of the micro-lenses, i. e. in the direction of the x-parallax. Thus, due to the continuous viewing of rapidly changing different small subsets of the entire stereo-laces, the observer is able to create his truly three-dimensional scene. Several depictions showing the actual statistics of the viewed image laces based on rigid geometric calculations serve to proof this concept.