Influencing Factors Of The Urabn Commercial Signage At Night On Visual Comfort Of Pedestrians

With the deepening of urbanization in China,nights of active city have become the characteristics of contemporary cities reflecting the degree of social and economic openness and prosperity.It has brought about the development of urban night scene environment lighting.For urban commercial districts,commercial signage constitutes one of the important elements of commercial environment lighting.On the one hand,for pedestrians and other users of pedestrian streets,they need to be able to clearly identify road signs and commercial signage,and cannot produce glare,otherwise it is easy to cause traffic safety problems.On the other hand,the setting of commercial signage meets the visual needs of pedestrians,while also taking into account the lighting energy consumption and light pollution.Therefore,commercial signage is the primary issue related to protecting the environment of urban commercial lighting area and maintaining the image of urban commercial lighting.This study mainly explored the impact of night commercial signage on pedestrian visual comfort through literature review,field research,field measurement,side-by-side ranking experiment and mathematical statistics analysis.The technical indicators of commercial signage are sorted out through literature review,and 16 key technical indicators are extracted.And a new comfort evaluation method and measurement method are proposed,which lays a foundation for the later research of technology route.In the process of field investigation,nine commercial streets were randomly selected according to stratified sampling in Shenzhen commercial lighting area.Ten subjects walked on each commercial street to observe,and two comfortable and two uncomfortable night commercial signage were freely selected.On 360 commercial signage obtained,68 were selected with agreements by over 2 participants.Among them,36 were considered comfortable or 32 were not comfortable,and they were taken as the object of field measurement of light,color and lighting parameters.In the process of field measurement,the brightness distribution of commercial signs was taken by imaging brightness meter,the chroma photographs are recorded by SLR camera,and the environment illuminance is measured by illuminometer.The results of correlation analysis between technical indicators of commercial signage and visual comfort of pedestrians show that among the 16 technical indicators,seven technical indicators related to brightness,color,stroboscopic and visual resolution are potential factors affecting visual comfort of pedestrians.In order to determine the comfortable range of four indicators,maximum brightness,uniformity,contrast of ambient brightness and average brightness ratio of signage to background,side-by-side ranking experiments were carried out in the laboratory.Among 68 commercial signage,48(selected by only 2 participants)of them were randomly divided into two groups,each of which required 10 subjects to rank.Four technical indicators(ambient brightness ratio,maximum brightness,brightness uniformity,and average brightness ratio of signage and background)and the comfort degree of commercial signage were analyzed.It can be found that the maximum brightness of the signage is less than 3000cd/m2 and the average brightness ratio of the signage to the background is less than 30.Based on the results of this research,a comfort analysis was conducted on the investigated commercial blocks and commercial signs,and the results showed that the three commercial blocks in Nanshan Vientiane Tiandi,Longgang Vankeli and Longhua Yitiandi were more comfortable,and were less comfortable in the manholes in Baoan District The commercial district and Gongming commercial district in Guangming District have put forward suggestions for improvement,providing theoretical supplements and extensions for future commercial lighting suggestions at night.