The regular reflection and irregular reflection of light
The light reflection
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 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 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 , Most objects 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 scattering of light , and diffused reflection makes non-luminous objects visible .
Not all the light rays which hits 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 .