Abstract
The eye blink rate, a major human physiological response, directly affects ocular diseases, such as keratitis and dry eye syndrome. It has been shown that the eye blink rate in normal eyes has a certain frequency for individuals, from 6–30 times/min. It was suggested in a previous study that the eye blink rate can be decreased during the viewing of high-intensity and realistic content. Therefore, in this paper, we examine the change of the eye blink rate during the HMD (head-mounted display) viewing of VR (virtual reality) contents; accordingly, we propose an algorithm to measure the eye blink rate as well as compare and analyze this rate in three different environments (natural, monitor, and HMD). We confirmed that IPD (interpupillary distance) and phoria affected the eye blink rate in each environment. In this experiment, 21 subjects (28.38 ± 6.87 years) were selected, and a paired t-test was performed for changes in the eye blink rate over 1 min for each environment. The IPD and phoria effects on the eye blink rate were confirmed using the Spearman’s correlation coefficient. In this experiment, the eye blink rate was decreased in the monitor and HMD environments compared with the natural environment, while that in the HMD environment was decreased compared with the monitor environment. The results of the correlation analysis of far IPD and the eye blink rate show no statistical significance or correlation. The correlation analysis of near IPD and the eye blink rate showed a strong positive correlation of the eye blink rate in the monitor environment. The correlation analysis of distance phoria and the eye blink rate showed a strong negative correlation of the eye blink rate in the HMD environment. The correlation analysis of near-field phoria and the eye blink rate showed a strong negative correlation of the eye blink rate in the HMD environment. It is expected that the results of this study will be used as a VR-viewing recommendation.
Highlights
Humans accept information from the external environment through various sensory organs.Among them, vision is higher than the other senses and plays an important role in the support of the other senses
The eye blink rate was decreased in the monitor and head-mounted display (HMD) environments compared with the natural environment, while that in the HMD environment was decreased compared with the monitor environment
This paper proposes an algorithm for the measurement of the eye blink rate, and the authors studied the effects of each of the realistic media environments on the eye blink pattern in the following three environments: natural, monitor, and head-mounted display (HMD)
Summary
Humans accept information from the external environment through various sensory organs. Vision is higher than the other senses and plays an important role in the support of the other senses. Human beings’ acquisition of external information frequently occurs via eye transmission [1,2]. One of the main human physiological reactions, is caused by the interaction between the levator palpebrae superioris muscle, which lifts the palpebral; and the orbicularis oculi muscle, which closes the eyelid. When the normally activated levator palpebrae superioris muscle is deactivated, and the orbicularis oculi muscle contracts, the eye closes. When the contraction of the Symmetry 2018, 10, 400; doi:10.3390/sym10090400 www.mdpi.com/journal/symmetry
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
