| Lighting can provide an important guarantee for the effective visual activity of humans.As the phenomenon of photobiological effects is revealed,indicators related to the health of light sources based on photobiological effects are gradually being proposed.Although the illuminance,color temperature,color rendering index,and other parameters of the light sources are the same,the influence on visual health varies depending on different spectral components.At the same time,the influence of the viewing lighting environment on display quality and visual comfort of the display is becoming an important research topic.The discovery of intrinsically photosensitive retinal ganglion cells(ipRGCs)and the gradual in-depth research on their visual and non-visual effects make contributions to this phenomenon.A combination of subjective evaluations and objective measurements was adopted in the thesis.Under different illuminance conditions,by collecting and analyzing subjective questionnaires,visual function parameters,alertness,eye movement signals,and physiological signals,the influence of spectral lighting environments with different ipRGCs illuminance levels on the display quality and visual comfort of the display device was investigated.The research content includes the following three aspects.Firstly,based on a 14-channel LED light source system,the spectrum was modulated and optimized.Thus,4 white light spectra with metamerism were selected for the experiment.The color temperature was the same: 4000 K,-0.03<Duv<0.03.For the 4 spectra,there were two illuminance levels: 300 lx and 500 lx,corresponding to the vertical illuminance of 100 lx and 150 lx at eye level.For each illuminance level,the Michelson contrast of perceived illuminance was about 11% for ipRGCs,and under5% for the other 4 photoreceptors.Then,under different illuminance conditions,the effect of lighting environments with different ipRGCs illuminance spectra on the dynamic process of pupil light response(PLR)was studied.The results showed that in a spectral lighting environment with higher ipRGCs illuminance,the pupil diameter was smaller,indicating that ipRGCs contribute to brightness perception.The maximum pupil contraction(CA)decreased slightly,indicating higher alertness and lower drowsiness.Furthermore,when the vertical illuminance at eye level was 100 lx,the ipRGCs illuminance had a greater impact on CA.The time for pupils to reach the maximum contraction amplitude was shorter.Besides,the pupils took less time to dilate to the initial value and recovered more quickly,indicating that ipRGCs contribute to post-pupillary response(PIPR).The difference in illuminance of lightings did not have a significant impact on the pupil light reaction process.Finally,under different illuminance conditions,the impact of lighting environments with different ipRGCs illuminance spectra on the display quality and visual comfort of display devices was studied.Subjective evaluations and objective measurements together showed that compared to the initial state,after the experiment,visual comfort decreased,visual fatigue increased,and alertness decreased,regardless of the different lighting environments.Under different illuminance conditions,the analysis results of lighting environments with different ipRGCs illuminance spectra showed that ipRGCs contribute to brightness perception.When the ipRGCs illuminance was high,the visual comfort was improved,and the alertness was higher.The impact of ipRGCs illuminance was greater when the eye-level illuminance was 100 lx.The illuminance contributed to the enhancement of display quality.There was an interaction between the illuminance and the ipRGCs illuminance.To obtain better visual comfort,when the illuminance was low,a spectrum with high ipRGCs illuminance could be used.When the illuminance was high,a spectrum with low ipRGCs illuminance could be used,and vice versa. |
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