Research On Visual Efficiency Of Projector In The Classroom

The study of the visual efficiency of the optoelectronic display is of great significance to improve the visual performance and visual experience of the viewer.In the past,the influence of display performance factors,environmental light factors and display content factors has been studied and discussed in three different aspects,and a series of rules have been found.On the basis of previous studies,we put forward hypotheses about the influencing factors of projection display for educational projectors,and used experimental methods to optimize the related optical parameters,so as to provide references for realistic projection display scenarios.This research includes two studies and three experiments.The study one is to explore the effect of projection illuminance on visual ergonomics,including two experiments.In Experiment 1,the effect of projection illumination on visual performance was explored by a standard search paradigm.In experiment 2,the effect of projection illumination on visual fatigue was investigated by video viewing task under constant ambient illumination.Study two,on the basis of study one,explored the effects of different projection illuminations on visual performance under different environmental illumination conditions.The results are as follows.Experiment 1 shows that under normal intensity illumination condition(65lux + 5lux),the visual performance of subjects increases with the increase of projection illumination(250lux~400lux).Secondly,when the subjective intelligibility score and eye comfort rating with projection illumination increased significantly increased.The results of experiment two showed that in normal strength environmental illumination conditions(65lux + 5lux),there are significant differences between the flash fusion frequency tested before and after the video viewing task when the projection illumination is 250 lux.Of the projection illumination at 250 lux and 350 lux,the decline of the flash fusion frequency after the video view task reached to the marginally significant,and the rest had no significant difference.It is known in the study one that in the projection display scene,visual performance is a more sensitive index to the change of projection illumination.The results of experiment three in the study two showed that with the increase of environmental illumination,the lowest projection illumination that can reach the standard of visual performance increased gradually,indicating that with the change of environmental illumination,we need to provide variable projection illumination in order to achieve better effects.The conclusions are as follows:(1)when the illumination is constant,the change of projection illuminance will affect the visual performance and asthenopia.(2)the best illumination value based on visual recognition performance is higher than the optimal illumination based on visual fatigue,and the visual recognition performance is more sensitive to the change of projection illumination.(3)the best illumination value based on short-term visual recognition performance is higher than that based on long time visual fatigue.(4)environmental illumination will affect the projector's display effect.With the improvement of environmental illumination,the projector's best illuminance value will also increase.