| The liquid crystal display(LCD)screen is used as the information display window,which is the main visual object of the user.Improper setting of display screen luminance parameter will affect visual acuity and comfort,and even cause long-term users to suffer from computer vision syndrome.Regarding the screen luminance,this thesis spreads out the human eye’s luminance perception comfort,and proposes a method to adjust the visual comfort luminance of the display screen.Three indicators are used to verify the visual performance and text readability of the adjusted display screen.The main research contents are as follows in the dissertation:Firstly,a method for calculating brightness based on high dynamic range image(HDRI)is studied.Through subjective and objective experimental design,according to the screen brigheness range under different visual comfort,a visual comfort evaluation method based on the screen brightness is obtained.The experiment combined five kinds of ambient lighting and ten kinds of screen luminance to simulate different lighting and display environments.In this simulated environment,a total of 50 groups of HDRI-based the screen brightness calculation experiments were carried out,and the pupil diameter and visual comfort of 6 subjects were measured.There are a total of 300 groups of subjective evaluation collection experiments.Through the analysis of the experimental results,the relationship between the screen brightness and the dimming level of the screen is obtained,and a method for adjusting the visual comfort luminance of the display screen is proposed.Secondly,the visual performance of the screen luminance of this method is verified.A visual search experiment was designed based on screen luminance with different visual comfort levels.In order to collect the reaction time,accuracy rate and eye movement image data of 10 subjects,a visual search experiment data collection system was established.Through the statistical analysis of comprehensive visual performance and reading visual performance of 30 sets of data,it is concluded that the visual performance of the screen luminance of this method can reach the best.Finally,the readability of the screen text of the method is verified.In order to analyze the eye movement image and calculate the fixation rate,this paper builds a gaze estimation system.An eye movement vector calculation method based on the horizontal offset feature of the line of sight is proposed.On 4 regression models,the data of the Columbia Gaze Data Set with the horizontal angle of the head of 20 subjects at 0 ° is used for experimental verification.The results show that,compared with the calculation method of binocular average eye movement vector,this method can further reduce the horizontal viewing angle error of the gaze point and improve the accuracy of the system.Using the proposed eye movement vector calculation method combined with the gaze judgment method based on the three-dimensional eye rotation model,a gaze estimation system is constructed,the gaze frames collected in the experiment are analyzed,and the obtained gaze point data is used to visualize the visual attention area using heat maps;Statistical analysis shows that the readability of the screen text is the best after adjusting the visual comfort luminance. |
