Abstract: Patent citation is an important approach for the technology spillover study, and is the measuring foundation for technical knowledge flow analysis. By using patent citation as a measure of technology spillover analysis, the study content of inter-firm technology spillover in one technical field and the expression of its result which is rarely mentioned in previous studies are played attention to. The application framework of the patent data of cross-citation,extra-citation, and self-citation for the inter-firm technology spillover analysis is proposed, the concept of visualization is introduced, and the study framework and method system for the inter-firm technology spillover analysis are constructed based on patent citation. Finally, a case study in the technical field of highway engineering is conducted to visually analyze the inter-firm technology spillover from both group and individual levels in order to provide the necessary information for innovation decision.

Key words: patent citation, technology spillover, visualization