Reflection of light or light beam/ray is a phenomena or process in which light ray strikes a surface and bounces back.
Incident ray :-
Incident ray is a ray of light that falls on the reflecting surface or strikes a surface from a source of light or an object. In simple terms, it is a incoming light ray which hits the reflecting surface.
Reflected Ray :-
Reflected ray is a ray of light that bounces back from the reflecting surface after reflection from the reflecting surface.
Angle of Incidence :-
Angle of incidence is an angle between the incident ray and normal to the point of incidence on the reflecting surface.
Angle of Reflection :-
Angle of reflection is the angle between the reflected ray and the normal to the point of incidence on the reflecting surface.
Normal :-
A perpendicular line drawn to the reflecting surface or it is a imaginary line at point of incidence or at the point where ray of light strikes is termed as the normal to the reflecting surface.
Point of Incidence :-
The point at which the incident ray touches the reflecting surface is termed as the point of incidence.
Reflecting surface :-
The surface which reflects the ray of light is termed as a reflecting surface.
Laws of reflection :-
when a ray of light strikes a reflecting surface and bounces back, these things happens :-
(1) The incident ray, the reflected ray, and the normal all lie on the same plane.
(2) The angle of incidence is always equal to the angle of reflection.
Angle of incidence= Angle of reflection.
Types of Reflection of Light :-
There are two types of reflection of light.
(1) Regular/Specular reflection.
(2) Diffused reflection.
Regular / Specular reflection :-
Regular or Specular reflection happens when rays of light strike a smooth and shiny surface. Such as a mirror, calm water, polished metal etc.
In regular reflection or specular reflection :-
(1) The reflected rays of light are parallel.
(2) The angle of incidence is equal to the angle of reflection.
(3) The image formed in this type of reflection is clear and visible.
Diffused reflection :-
Diffuse Reflection occurs when rays of light strike a rough, unpolished and uneven surface. Such as a piece of paper, non metalic rough and unpolished objects etc.
In diffused reflection :-
(1) The reflected rays of light scatter in many different directions.
(2) The reflected rays of light does not form a clear, visible image.
Difference between regular / specular reflection and diffused reflection :-
(1) Regular/specular reflection happens on the smooth and polished reflecting surfaces. On the other hand diffused reflection happens on a rough reflecting surface.
(2) In case of regular/specular reflection, the reflected rays and the incident rays are parallel to each other after reflection occurs. On the other hand, In case of diffused reflection, after reflection occurs, both incident rays and reflected rays are not parallel to each other.
(3) In regular/specular reflection, clear and visible image is formed. On the other hand, in case of diffused reflection, scattered rays do not form clear and visible images.
Practical application of reflection of light :-
The reflection of light is a basic concept in physics, where the ray of light bounces off the surface. But this phenomenon depends on the nature or type of the surface. This effect of light is termed as the law of reflection. Reflection of light from the surfaces provides various practical applicability. This phenomenon of light plays a very vital role in various aspects in daily life. Below some important applications of the reflection of light are given:-
Reflection of light in mirror :-
Mirrors are one of the most commonly used tools for various purposes in our everyday life. A mirror is a smooth surface which reflects light with concrete efficiency. It produces clear and distinct image. In everyday life, mirrors are utilised in personal grooming. It is used in vehicle rearview mirrors, and also used for decoration purposes. The reflected light from a mirror creates or generates a virtual image, which is very much useful for seeing objects.
In periscopes :-
Periscopes are basically used in submarines or military tanks. It depends on the principle or phenomena of reflection of light. A periscope helps to see or observe objects outside their direct line of sight. Which means it is helpful to see through a system of mirrors. In periscopes, light enters the periscope and then light reflects off the mirrors. It allows you to see an object from a hidden position or from the indirect line of sight.
In telescopes and microscopes :-
Telescopes and microscopes contain mirrors and lenses. It follows the principle of reflection of light. In telescopes and microscopes, the lenses gather and focus light rays. In telescopes, lenses are utilised to reflect light from distant starts, galaxies, and other celestial bodies. It helps to see or observe these objects. In the same way, in microscopes, mirrors reflect light from the tiny or extremely small objects. Due to this effect these tiny objects can be visible. It helps to see very tiny cells or bacteria. Usually these cells and bacteria are invisible with the naked eye. These two instruments help to see clear magnified images.
Used in cameras :-
In the world of photography and videography, reflection plays an essential role. Cameras utilize lenses and mirrors which reflects the light entering through the lens. It allows the photographer to click their photoshoot or video shot. This phenomenon of light helps to focus and capture images, and make adjustments according to the need of the image.
Helps in generating solar power energy :-
Reflection of light is also widely utilised to concentrate sunlight and it helps to generate solar power energy. Some specific reflectors or mirrors / lenses are designed in solar thermal power plants or solar panel to concentrate sunlight into a smaller area. Solar power energy is very much useful in the near future. By concentrating a large amount of sunlight into a collector or solar panel, this system can generate heat or electricity. Solar plants help to generate electricity through sunlight and the phenomenon of reflection of light helps in this regard.
In laser technology and optical Communication system :-
Laser technology and optical communication systems very much depend on the effect of light. In this technology, equipment is designed with the help of mirrors, lenses and other reflective surfaces to focus the laser beam of light. This is used in different fields such as communication, presentation, medical treatments etc. In optical communication systems, light reflections help to send data to a long distance place with high speed and quality.
Conclusion :-
The reflection of light is a very useful effect or phenomenon. Reflection of light is not just a physical principle or theory, but it has a practical applicability in daily life and it expands the scope of science and technology.
Above given some basic concepts of reflection of light and their related topics. I hope, students will study deeply and understand the basics of reflection of light.
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