Because the road surface is diffuse, some of the reflected light will enter B's eyes; The moon is behind B, and the water surface is specular, so the reflected light can't enter B's eyes, so B's classmates see that the water surface is darker than the road surface.
The picture below is diffuse reflection.
The following picture shows specular reflection.
Extended data:
Diffuse reflection refers to the light emitted by the light source entering the sample and returning to the surface of the sample after repeated reflection, refraction, scattering and absorption. Diffuse reflection light is the light after analyzing the interaction with the molecules inside the sample, which carries rich information about the structure and organization of the sample.
Compared with diffuse reflection light, although the transmitted light also carries the structure and tissue information of the sample, the intensity of the transmitted light is affected by the thickness of the sample and the irregularity of the optical path during transmission, so the diffuse reflectance measurement is more direct and reliable in extracting the composition and structure information of the sample.
Specular reflection refers to the reflection of reflected waves (electromagnetic waves, or sound waves and water waves) in a certain direction;
The included angle (reflection angle) between the reflected wave direction and the normal of the reflecting surface is equal to the included angle (incident angle) between the incident wave direction and the normal of the reflecting surface, and the incident wave and the reflected wave are in the same plane.
When taking pictures, it is necessary to avoid the specular reflection light from entering the camera lens. Because the specular reflection light is extremely strong, it will form a white bright spot on the photo, which will affect the appearance of the ground object itself in the photo.
Baidu encyclopedia: diffuse reflection
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