The regular reflection and irregular reflection of light
The light reflection is the returning back of light waves in the same medium on meeting a reflecting surface, and the surface at which the reflection takes place is called the reflecting surface, The light reflection is classified according to the nature of the reflecting surface into the regular (uniform) reflection, and the irregular (non-uniform) reflection.
The light reflection
The reflections of light are usually caused by the shiny things, such as the mirrors that show a reversed image of whatever is placed in front of them, The image seems to be as far behind the mirror as the object is in front of it.
The mirrors are very smooth polished pieces of metals or plastic which reflect all the light that falls on them, and the reflection appears to be behind the mirror, The surface of a clean mirror causes a regular reflection, while the dirty mirror surface causes irregular manner.
We use the mirrors when checking our appearance or driving, They also play an important role in the telescopes, the microscopes, the cameras, and other optical ( light-based ) instruments.
Not only the mirrors make the reflections of light, But Most objects also reflect some of the light that falls on them, we see familiar objects like the grass, the trees, and the sky only because they reflect the light from the Sun into our eyes.
Regular (uniform) reflection
The regular reflection is the reflection of light rays when they meet (fall on) a smooth (uniform) and glistening surface, where the incident light rays are reflected in one direction, When a beam of parallel light rays is incident on a smooth and plane surface, the reflected rays will also be parallel, and it is called the regular reflection.
The regular reflection takes place when the light rays are incident on a polished smooth surface like a plane mirror, a stainless steel sheet and a thin sheet of aluminum, so, the reflected rays of light move only in a fixed direction.
We are able to see a very clear reflection on the smooth surface, Every light ray is reflected perfectly from the surface and bounces back in a regular way, The reflected image is very clear and sharp.
Irregular (non-uniform) reflection
Irregular reflection is the reflection of light rays when they meet (fall on) a rough (non-uniform) reflecting surface, where the incident light rays are reflected in different directions.
When a beam of parallel light rays is scattered in all directions, So, the parallel rays incident on the surface will reflect in different directions, and it is called irregular or diffuse reflection.
Irregular reflection or diffused reflection takes place when the light rays are incident on a surface like a wall, the wood, a leaf of a tree, a piece of leather, a piece of paper or a piece of wool, which are not smooth or polished, so, the different portions of the surface reflect the incident light rays in different directions.
There is no definite image formed, but the surface becomes visible, It is commonly known as the scattering of light, and diffused reflection makes non-luminous objects visible.
Not all the light rays which hit an object are reflected, Some of the incident light rays are absorbed, The brightness of an object depends on the intensity of the incident light rays and also on the reflectivity of the object.