The realization of map functions is usually paid much more attention to than the visualization quality of map in the development of electronic map. As a result, the visualization effect of electronic map is unsatisfactory. The visualization quality of electronic map is directly related to user's understanding of geographical information and influences the application of electronic map. Along with extensive expansion and application of electronic map, visualization effect of electronic map has already become an important aspect to evaluate electronic map products. To examine the evaluation
and the control techniques of electronic map visualization quality and to establish evaluation standards of electronic map visualization quality are of great significance at present. Based on the experiences in electronic map design, development of electronic map platform and professional application, the authors summarize several factors affecting visualization quality of electronic map: user interface, display capacity, visual effect, display speed, dynamic labeling, real-time display, legend and symbol design, and other aspects including temporal effect, mark effect, dynamic generalization, and dynamic projection. Combining with the practice in developing an electronic atlas system called eMapSee, the authors
analyze related control techniques of visualization quality of electronic map from these aspects: friendly user interface,
legibility and beauty of display effect, fast map display, real-time map display, and introduce how these techniques are used in practice.