Abstract:

Objective To explore the different effects on human visual fatigue induced by watching linear polarized liquid crystal display(LCD) and circular polarized using eye movement analysis. Design Experimental study. Participants 60 healthy young subjects whose refractive status are emmetropia. Methods 60 subjects were divided into two groups randomly. Two groups were arranged to view linear polarized LCD and circular polarized LCD respectively, blinking frequency and blink duration time were recorded using eye tracker. Main Outcome Measures The real time eye movement parameters blink frequency and blink duration time. Results While viewing the video, blink frequency and blink duration time of two groups decreased at first and then increased till the end. Blink frequency of the linear polarized group decreased to 13.95 times/min from the original 15.83 times/min, blink frequency of the circular polarized group decreased to 11.46 times/min from the original 13.93 times/min. Blind frequency of two groups increased at the latter period because of visual fatigue, blink frequency of the linear polarized was 22.63 times/min at the end of stage, and blink frequency of the circular polarized group was 16.33 times/min. Blink duration time of the linear polarized group ranged from 2272 milliseconds/min at the beginning to 4084 milliseconds/min at the end of stage. Blink duration time of the circular polarized group ranged from 2001 milliseconds/min at the beginning to 2596 milliseconds/min at the end of stage. The changes of blink frequency and blink duration time before and after viewing the video in two groups was statistically significant with P value 0.030 and 0.031 respectively. Conclusion While viewing video, blink frequency and blink duration time of two groups decrease at first and then increase in the overall trend, the changes of blink frequency and blink duration time of the linear polarized group were significantly higher than those of the circular polarized group. Circular polarized LCD causes less visual fatigue. (Ophthalmol CHN, 2016, 25: 63-67)

Key words: eye tracker, visual fatigue, blink frequency, blink duration time