The basic theory of the principle of equivalence is to compare the technical composition of the accused infringer with the corresponding technical characteristics recorded in the patent claim. If ordinary technicians in the technical field can associate with the patentee's patent specification and patent claim without creative intellectual labor, such as using equivalent replacement, component replacement, decomposition or merger to realize the invention purpose and positive effect of the patent, and compared with the patented technology, the purpose, function and effect are the same or basically the same.