What is specular reflection?

A beam of parallel light hits a plane mirror, and the reflected light is parallel. This reflection is called specular reflection.

When a beam of light hits an object in an uneven way, its reflected light also points in different directions, not parallel, so we can see the same object from different places. This reflection mode is called "diffuse reflection". Otherwise, if they are all specular reflections, we can only see objects from specific places.

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.

Similarities and differences between specular reflection and diffuse reflection;

Specular reflection and diffuse reflection have the same reflection angle and incident angle. The only difference is that the mirror reflection surface is relatively flat, so the light beam is relatively uniform and the reflection direction is relatively consistent. The uneven reflecting surface of diffuse reflection leads to the disorder of light beam. Both conform to the law of reflection.