The Visual Fatigue Of 2D/3D Display Under Different Lighting Conditions

The development of three-dimensional display and new lighting technology brings our lives with more colorful visual experience, the 3D display creates realistic visual feelings and a strong sense of immersion, while also inevitably have some negative impacts on human health, one of which studied most extensively is visual fatigue. In this thesis we study the effect of lighting and 3D display on visual fatigue by means of making a comparison between watching 2D and 3D displays under different lighting conditions and we aimed at finding out stable objective parameters to measure visual fatigue.Both subjective (questionnaires) and objective measurements are adopted in the study of visual fatigue.5eye-related parameters:the flicker fusion frequency (CFF), positive and negative relative accommodation (PRA/NRA), near point of accommodation (NPA) and near point of convergence (NPC) are selected as the items of objective measurements.In order to compare the effects of different lighting and display content on visual fatigue, six kinds of experimental conditions were tested. Results showed that after watching movies about 1 hour and 30 minutes, subjective fatigue scores were significantly increased, CFF, NRA and PRA significantly decreased, while NPA and NPC increased, indicating that visual function caused by visual fatigue decline temporarily. After making a comparison of visual fatigue induced by different lighting conditions we found that it is most likely to cause visual fatigue under dark environment. It is more acceptable to watching traditional 2D displays with the temporal-modulated LED lightings. But this kind of lighting is not suitable for watching time-sequential 3D display. In addition, the study found that there is no significant difference between 2D display and 3D display on visual fatigue.In order to study the trend of visual fatigue with time, a 60 minutes long experiment was set up to obtain the changes of ocular parameters, the results showed that subjective score is rising and CFF has fallen in the whole measuring process, and NPA and NPC shorten slowly and reached a minimum value at 50 minutes, while in the last 10 minutes began to be far away. This indicated that conflict between accommodation and vergence may not necessarily lead to the decline of visual function, but there is a process of mobilization of accommodation reserve until watching video for 50 minutes the fatigue became obvious.This paper provides a reference of the illumination lighting source while watching the videos, and provides several ocular parameters which can be used to measure the visual fatigue for subsequent researches.