Diffuse Reflection

Reflection from a diffusing surface such as a powder layer. There are two measurement methods: one in which the angle of incidence is kept constant and the reflected light intensity in the direction of a constant reflection angle is compared to a standard sample (a magnesia-coated surface is often used), and the other in which the integrated value of a 2π solid angle for the reflection angle is compared and measured. The integrating sphere method is an example of the latter. In addition to the spectroscopic characteristics of the optical constants specific to the material, the structure of the surface and within the layer is also involved. P. Kubelka's two-constant theory is widely used as an analytical method.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

粉体層のような拡散面による反射．測定法は入射角を一定にして，一定反射角方向の反射光強度を標準試料(マグネシア塗布面が多く用いられる)と比較測定する方法と，反射角について2π立体角の積分値を比較測定する方法とがある．積分球法は後者の一例である．物質固有の光学定数の分光特性のほかに，表面や層内の構造が関与している．解析法としてはP. Kubelkaの二定数理論が広く用いられている．

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