The Fundamental Research On Human Visual Comfort Effected By Different Factors In Watching 3D Films And Televisions Based On EEG And ERP Approaches

While bringing immersive experience,3D films and televisions have a certain negative impact on visual comfort.Due to the unclear 3D visual discomfort mechanism presently,the uniform standards for 3D evaluation is still lacking.The purpose of this thesis is to explore the uncomfortable reasons,to find the comfort zone of the related factors,and to lay the foundation of reducing visual discomfort.Classical brain function techniques,electroencephalogram(EEG)and event-related potential(ERP),were used in this thesis.Three key stereoscopic film factors,disparity,brightness difference and border effect,which affect stereo fusion and spatial construction,were selected.A complete and innovative research scheme was designed to meet the research needs.Valid data like attention degree,EEG complexity,VEP,brain network and source location acquired from 85 healthy subjects were analyzed.The synchronous acquisition combining objective EEG/ERP signals and subjective evaluation shortened the experimental duration.The crucial conclusions include:(1)Comfort index of stereoscopic film factors: the short-term(within 220 seconds)3D segments with excessive background disparity will not cause more visual discomfort than the normal,the crossed disparity should not be more than 1 degree,the brightness difference should not exceed 40%,and the upper border effect should be minimized.They reveal the existing 3D technical problems caused visual discomfort,i.e.,the index greatly exceeds the comfort range.(2)Quantitative parameters assessed 3D visual comfort: P3 components in frontal,temporal and occipital lobes were regarded as the evaluation parameters by comparing the brain functional network.It makes the quantitative evaluation for 3D visual comfort possible based on EEG and ERP.(3)An EEG tracing scheme was proposed to explore the brain function linked to 3D visual comfort.EEG results like the frontal and temporal lobe relating closely to 3D visual comfort level were in accordance with f MRI studies.It supports the 3D visual comfort evaluation through ERP brain function characteristics.(4)An optimization model of 3D visual comfort level is established.This model can effectively alleviate the negative effects in 3D viewing.The thesis discusses the mechanism and evaluation of stereo visual discomfort in multi-level.It lays a foundation for 3D visual discomfort evaluation,alleviation and assessment standards and provides a reference for the development of 3D technology and devices.