为了比较亮度均匀度对可见度水平的影响,深化可见度的设计方法,选取了截光型、半截光型道路照明灯具,以不同的灯具布置方式进行实验研究;利用小目标物可见度计算方法,研究亮度均匀度与计算点可见度水平分布的关系。结果表明,当均匀度较好时,应使路面亮度分布尽可能保持统一,各计算点的可见度水平同为正(或同为负);当均匀度不能保证较好时,可有意降低路面亮度均匀度,并使路面各点的正负可见度增大,从而使整条道路可以得到较高的STV值;在道路照明设计中还需要建立一个限定道路上可见度水平分布的方法。
To determine the influence of luminance uniformity on visibility levels, and to study methods of visibility design, we carried out experiments having different luminaire collocation modes. Cut-off luminaire and semi-cut-off luminaire were used in these experiments. The relationship of luminance uniformity and visibility level distribution of targets was studied based on small target visibility calculation methods. The results indicate that if luminance uniformity is good, the road luminance distribution should remain uniform, then the visibility levels of all targets are positive (or negative). If luminance uniformity is insufficient, it can be reduced intentionally and the visibility level of each target can be increased. A higher STV value can be gained for the entire road. The method of limiting road visibility level distribution should be established in road lighting design.