Comfort Evaluation Of 3D Display & Study On Motion-in-Depth Basing On ERPS

With the high development of 3D techniques, 3D applications extremely prevail during our daily life. However, the comfort problem of 3D display is still disturbing us. Nowadays, display manufacturers and researchers at home and abroad evaluate 3D display comfort primarily relying on subjective approaches. However, subjective evaluation is likely to deviate from the reality or the conclusions related are inconsistent to each other, due to human factors or the essence that the approach is on the basis of memory. Subjective evaluation's temporal resolution is so low that it can't trace psychological activities, and relating means are somewhat monotonous. By contrast, objective evaluation has overcome the defects of subjective evaluation. Thus objective comfort evaluation of 3D display has been a hot topic.Incongruity between two viewpoints is one of the important factors affecting visual(dis)comfort of 3D display. Then, an approach of combining subjective evaluation to objective one is adopted in this paper to study the geometrical deviation of 3D incongruity.Objective approaches to 3D vision evaluation mainly contain the evaluation basing on algorithms,HVS(Human Vision System), ERPs(Event-Related Potentials), fMRI(functional Magnetic Resonance Imaging), the combination of ERPs and fMRI, etc. Overall, considering the strengths and weaknesses of these approaches, ERPs technique is utilized in this paper to evaluate geometrical deviation, including size, rotation, chrominance and luminance. Principles and advantages referring to ERPs are elaborated in details afterwards as well as the way how to apply ERPs technique into objective evaluation experiment. ERPs, a voltage fluctuation related to some specific physical/mental event in temporal domain, is extracted from EEG signals which are evoked by external stimulating signals via utilizing overlay techniques.To achieve a general conclusion, targeted experimental stimuli are chosen for each attribute. The paradigm adopted is derived from the paradigm Go/No-go, called the Double-Stimulus paradigm in this paper. To explore human brain responses to 3D movement, a study on motion-in-depth is done through simulating realistic details using 3D techniques.As a result, it is discovered that size, rotation, chrominance and luminance geometric deviation can elicit measurable ERPs on cerebral cortex and perception or waveform difference increases significantly with deviation level up. The experimental results illustrate that the component evoked is appropriate to do the geometrical deviation evaluation and obtain the incongruity attribute thresholds. The perception to motion-in-depth experiment shows that components evoked refer to perception to whether an object is moving or still, to whether a motion is accelerating or decelerating, and to the outline or details of an approaching object.