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为了给道路交通标志的设计与应用提供参考,针对LED点阵式发光标志、LED半透式发光标志和传统逆反射标志,考虑光照强度、闪烁频率、发光形式等因素的影响,进行了交通标志视认性能的驾驶试验研究.采用方差分析研究各个因素对标志视认距离影响的显著性及其交互作用.基于驾驶模拟器进行视认性能对比试验,采用配对样本t检验比较了半透式发光标志与逆反射标志的视认距离,并根据试验数据分析不同光照强度下半透式发光标志的最佳亮度区间.结果表明:在光照强度为200lx的下午,LED主动发光标志相对于逆反射标志只增加了2～4m的视认距离;而在光照强度为0.5lx的晚间,视认效果则提升显著,点阵式和半透式发光标志的视认距离相比逆反射标志分别提升了39.7％和80.4％.闪烁发光无论快慢,对于LED主动发光标志的视认效果均无提升.另外,半透式发光标志的亮度过高时会产生眩光效应,不利于驾驶人辨识标志内容,且最佳亮度区间随着环境光照强度的变化而变化.因此,在光照条件较差的情况下,推荐采用常亮LED半透式发光标志.“,”Driving tests were performed to study the visibility of signs using LED dot-matrix displays, LED transflective displays, and conventional retro reflective screens, to provide a reference for the design and performance of road traffic signs. The effects of environmental luminance, flashing frequency, and lighting forms were analyzed. Variance analysis was used to study the significant effects and interactions of all factors on the visible distance. The paired sample t-test was performed based on the data collected from driving simulators to compare the visible distance between signs using transflective displays and retro reflective screens. In addition, the optimal luminance interval for signs using transflective displays under different environmental luminance was analyzed. The results indicate that the visible distance for LED active luminous signs is greater than that for signs using retro reflective screens by 2-4min the afternoon (200lx). The visible distance for signs using LED dot-matrix displays and LED transflective displays increases by 39. 7％ and 80. 4％, respectively, at night. The visibility of LED active luminous signs does not improve with flashing light irrespective of the flashing frequency. The results obtained using driving simulators indicate that the glare from excessive brightness causes discomfort to drivers and is not conducive to sign recognition. The optimum luminance interval of LED signs was observed to vary with the changes in the ambient brightness. It is recommended using signs with steady LED transflective displays under poor lighting conditions.