Lightness perception based on perception of shadow and perceived brightness

2015 Fiscal Year Final Research Report

• Project/Area Number: 25730166
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Kansei informatics
• Research Institution: Ritsumeikan University
• Principal Investigator: TOKUNAGA RUMI 立命館大学, 立命館グローバル・イノベーション研究機構, 研究員 (80573914)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 影の知覚 / 空間の明るさ感 / 照明の認識 / 輝度勾配 / 明度知覚

Outline of Final Research Achievements

We see shadows everywhere. Shadows are the visual response to an absence of light, in other words, all shadows are intangible. We usually don’t pay attention to shadows, but we sometime can aware that a space is brightly illuminated by seeing dark shadows. It is not revealed how shadow affects our brightness perception of a space. In this research, we tested whether the perception of shadow affects the perception of brightness of a space. Using multidimensional scaling we analyzed the dissimilarity structure produced by different intensity of illuminances and shadows. Experimental results showed that the apparent brightness of the space was proportional to the intensity of illuminance and to the shades of shadow. It indicates that our visual system uses information of shades of shadow to estimate the apparent brightness of the space.

Free Research Field

視覚情報処理、感性工学