Rethinking Design Similarity in Intellectual Property: A Consumer Judgment Cognitive Model Based on Form Similarity and Essence Similarity

Abstract With the increasing importance of industrial design in innovation and intellectual property governance, traditional methods of similarity judgment have been questioned due to their subjectivity and lack of quantitative basis. This study, based on psychophysics and cognitive psychology, proposes a consumer perception model with dual dimensions of Form Similarity and Essence Similarity to explore how users make similarity judgments of industrial designs. The research uses vases as experimental materials, categorizing their appearance into primary and secondary features, and measures the differences in cognitive coverage, sensitivity to differences, and subjective judgments among different consumer groups through a three-stage experiment. The results show that primary features play a dominant role in judgment. When the similarity exceeds 74.24%, consumers are more likely to consider the shapes similar. Moreover, the judgment exhibits non-linear characteristics, with experienced consumers demonstrating higher recognition stability and sensitivity. The study not only builds an operable similarity evaluation framework but also provides interdisciplinary policy insights for intellectual property review, consumer research, and design management.