Recently, with the advancement of autonomous driving technology, the function of external lamps has been changed. Previously, the focus was on the visibility of drivers, but with the advancement of autonomous driving technology, the concept of autonomous driving systems has been developed. Accordingly, the trend of automotive lamp lighting systems has been developed in terms of design, e-HMI (exterior-human machine interface), It is developing in accordance with three major fields such as sensor connection. Therefore, this paper will cover the prior development of road content projection headlamps that enable e-HMI implementation to reflect these new trends. Since the technology is mass-produced and sold by several manufacturers, our company also needs to quickly develop and apply the technology in advance. Only four types of symbols are allowed in European law. Although it is still impossible for the symbols to be guided in the direction of progress, it is expected that they will be allowed soon as the European law discussion is actively reviewing the permission. This paper includes a detailed review for setting the symbol position of the road projection, a process for setting the light source module, reviewing development goals such as contrast ratio/equality/sharpness, and a process for reviewing formulas to establish detailed size requirements for symbols projected on the road surface. Based on this research process, we will discuss two concepts of road projection light source structure that were finally developed, and detailed projection quality of road symbols that satisfy the development goal. We will also introduce various reviewed road symbols and video scenarios.