Question

what are necessary conditions for reflection to be a regular reflection

Answer 1

Dear Student,
Light reflected from smooth, plane and polished surfaces are termed as regular reflections. When a beam of parallel light rays is incident on a such surfaces, the reflected rays will also be parallel and move along particular direction making a sharp image. Regular reflection occurs when the light rays are incident on a polished smooth surfaces like a plane mirror, a shiny metal sheet, etc.

Diffuse or irregular reflection is the reflection of light rays when they fall on a rough or non-uniform reflecting surface, where the incident light rays are reflected in different directions. The parallel rays incident on the surface will reflect in different directions, and gives a blurr image. Such reflection takes place when the light rays are incident on a surface like a wall, a wood, a leaf , a piece of leather, a piece of paper, etc., which are not smooth or polished, so, the different portions of the surface reflect the incident light rays in different directions.

The necessary condition for regular reflection is:
1. The reflecting surface must be flat, smooth, polished and reflecting.
2. The surface must also be dust free.

Regards