Based on the perceived contrast method in road tunnel lighting, Commission Internationale de l´Eclairage (CIE) defined the contrast revealing coefficient q_c. The research report CIE 189-2010 recommended that contrast revealing coefficient q_c was one of the indicators of tunnel lighting quality evaluation system. Many studies suggested that the value of q_c was 0.6 under counter-beam lighting in tunnel lighting threshold zone. The value of contrast revealing coefficient was 0.2 under symmetric lighting. However, no studies have recommended the optimal value of contrast revealing coefficient under different lighting systems. The optimal value of contrast revealing coefficient was closely related to visual efficacy and driving safety in road tunnel lighting. Based on the range values of contrast revealing coefficient and visual efficacy experiment, this paper aimed to study the optimal values of contrast revealing coefficient under different lighting systems. The research results were as follows: the optimal value of contrast revealing coefficient q_c was 0.20 under symmetric lighting and the optimal value of q_c was 0.85 under counter-beam lighting. The optimal value of contrast revealing coefficient was 0.17 under pro-beam lighting.

基于道路隧道照明中的感知对比度方法，国际照明委员会（CIE）定义了对比度显示系数q _c。CIE 189-2010研究报告建议对比显示系数q _c是隧道照明质量评估系统的指标之一。许多研究表明，q _c的值在隧道照明阈值区域的反光照明下为0.6。在对称照明下，对比显示系数为0.2。然而，没有研究推荐在不同照明系统下对比度显示系数的最佳值。对比显示系数的最佳值与道路隧道照明的视觉效果和驾驶安全性密切相关。基于对比显示系数的范围值和视觉效果实验，旨在研究不同照明系统下对比显示系数的最佳值。研究结果如下：对称光照下对比显示系数q _c的最优值为0.20，q _c的最优值为在反光束照明下为0.85。在前束照明下，对比度显示系数的最佳值为0.17。