夜间城区可变信息标识的易读性和舒适度研究

Study on Legibility and Visual Comfort of Variable-message Signs in Urban Areas at Night

可变信息标志(VMS)作为一种重要的交通标志,在交通控制中得到了广泛的应用。本研究评估了夜间城市区域VMS的字体亮度、颜色和背景亮度对易读性和舒适度的影响。首先,调查、测试典型城市区域VMS的背景亮度,并将其分为高、中或低三个等级(分别为3.0、1.0 cd/m^(2)或0.1 cd/m^(2));其次,建立了不同视力条件下实验视觉识别距离的计算模型,根据感知的心理物理量值确定实验亮度点,并利用Landolt-C环开展易读性及舒适度实验;最后,获得了在不同背景亮度下,同时满足易读性及视舒适的红色、绿色和黄色的亮度变化趋势和合理亮度区间。结果表明,不同颜色在不同背景亮度下具有不同的亮度区间。本研究对于确定VMS字体的合理亮度、提高道路交通的安全性和效率具有重要意义。在未来,这些研究结果有望为VMS设置和管理提供依据和参考。

Variable-message signs(VMSs),which are an important type of traffic sign,have been widely used in traffic control.This study examines the influence of text luminance,text colour,and background luminance of VMSs on visual comfort and legibility in urban areas under nighttime vision.First,the background luminance of VMSs in typical urban areas is investigated,tested,and classified as high,medium,or low depending on the obtained values(3.0,1.0 cd/m^(2),or 0.1 cd/m^(2),respectively).Second,a calculation model is established for the experimental visual recognition distance under different visual acuity conditions,the experimental luminance interval is determined based on psychophysical magnitude perceived,and a legibility and visual comfort experiment is performed using Landolt-C rings.Finally,the reasonable luminance interval and changing trends of luminance for red,green,and yellow colours under different background luminances are obtained such that the visual comfort and legibility requirement is satisfied.The results indicated that different colours have different luminance interval under different background luminances.This study is of great importance in determining the reasonable luminance of VMS texts and improving the safety and efficiency of road traffic.In the future,these research results are expected to serve as guidelines for VMS setup and management.