Establishment of a method for measuring optical reflection characteristics on curved surfaces and its application to cultural heritage archives

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K11954
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 61010:Perceptual information processing-related
• Research Institution: Tokyo Polytechnic University (2022-2023); Chiba University (2021)
• Principal Investigator: Inoue Shinichi 東京工芸大学, 工学部, 客員研究員 (70743813)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: BRDF / 光反射特性 / 曲面 / 光沢 / 光沢ムラ / 質感

Outline of Final Research Achievements

We developed a new measurement technology for physical light reflection characteristics (BRDF, gloss unevenness), which affects gloss, which affects texture. As a result, we developed a BRDF measurement technique for curved surfaces that was difficult to measure conventionally by considering this as a reflection of a paraboloid, and using condensed lighting. Additionally, in order to analyze the phenomenon in which gloss unevenness appears differently depending on the angle of light, we have developed a variable angle gloss unevenness measurement technology with high angular resolution. We proceeded to develop a prototype of these as measuring devices. New light reflection characteristics (BRDF, gloss unevenness) can now be measured numerically. The relationship between these BRDFs, gloss unevenness, and perception was analyzed through experiments. We considered using it for cultural property archives and CG.

Free Research Field

視覚情報工学

Academic Significance and Societal Importance of the Research Achievements

光沢は人間の知覚である質感に大きな影響を与える．このため光沢は重要な品質特性として産業界で広く計測評価されてきた．本研究により，新たに曲面のBRDF 計測技術が開発されたこと，角度分解能の高い変角光沢ムラ計測技術が開発されたことは，産業界においては品質管理，製品開発において従来は人間に頼っていた評価を数値化できる可能性がある．さらに，仏像のような光沢を有する文化財の光反射特性をアーカイブとして残すことが可能となる．学術的には，人間が素材に対する高級感のように，従来解析する上で計測できなかった光沢についての新たな情報が数値化できるようになる．