15 Specular Reflection Examples: Detailed Insight And Facts

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This article discusses about specular reflection examples. The phenomenon of bouncing back of light when it falls on a polished surface is called as reflection.

Specular reflection is very common and typically means a mirror like reflection. It can be observed in our day to day lives. This article first discusses about what is reflection, types of reflection and then about different examples of specular reflection.

What is reflection?

As discussed in above sections, the light bounces back after falling on a polished or shiny surface. This phenomenon is called as reflection.

When we see ourselves in the mirror, it is due to reflection. Only polished surfaces can reflect back the light completely. The light will pass through the glass if it is transparent from both the sides. One side has to be opaque in order for the glass to exhibit reflection. We will discuss about how reflection takes place in below sections of this article.

What is specular reflection?

Specular reflection is a type of reflection which means mirror like reflectance of light when it falls on a shiny body.

Specular obeys the law of reflection. The angle made my incident ray and normal is the same as the angle made by reflected ray and normal. We shall see more about law of reflection and mechanism of reflection in below sections.

specular reflection examples
Image: Specular reflection on water body

Image credits: Wikipedia

What is scattered/diffuse reflection?

In scattered reflection, the rays of reflection are unevenly scattered in all directions unlike specular reflection.

In diffuse reflection, the reflected rays make unequal angles with the vertical. The reflected rays scatter in multiple directions rather than one.

Examples of specular reflection

Specular reflection can be observed every where in our day to day lives. Whenever we go out in public places or even sit inside our classrooms, specular reflection can be observed in some or the other way.

Let us see more about specular reflection by looking at some examples. They are given below-

Conventional plane mirror

A conventional rectangular plane mirror like we see in washrooms and wardrobes follow the principle of specular reflection. The incident rays come from the object standing in front of the mirror, these incident rays are reflected back at the same angle. Here, the angle of incidence is zero hence the reflected ray also makes zero degrees with the normal meaning both incident ray and reflected ray co incide each other. The object’s reflection will be visible. 

Concave mirrors

In concave mirrors, we can usually see an inverted image because of the curvature of concave mirrors.

Glasses on the side walls of malls/shops

Glasses on the side walls of malls are cleaned thoroughly, this way the glasses become a polished surface. Hence we can see our own reflection on the glasses when we go near those glasses.

Polished ceramic mug

A ceramic mug also acts like a mirror when it is polished properly. We can see our own reflection when we are holding the mug.

Glare on sunglasses

When we clean the sunglasses, they become polished surfaces. Hence a person standing in front of us can see their reflection from our sunglasses.

Steel utensils

Steel utensils also act like polished surfaces. We will be able to see reflection of the object if it is placed near to the mirror. Metal body phones- Metallic finish acts like a polished surface, any light falling on such a surface is reflected back.

Car body

A car body is usually made of glass fiber on which a polished finish is given. Due to polished finish, we can see our reflections when we stand beside a car. A dirty car won’t be able to reflect our image as it is not polished.

Water body

A water body such as lakes and rivers are usually still and reflects the objects near them. A perfect example of this is reflection of sky in the river and lake. The lake appears to be blue because of reflection of sky.

Polished plastic surface

When a plastic surface is polished, we can see our reflection on it. This is also due to specular reflection.

Ionospheric reflection

Radio waves are reflected in ionosphere. This is an example of specular radiation of waves.

Reflection of radar waves

When the enemy aircraft enters our air base, our radar detects it. This happens because the radar waves are reflected back to the radar after striking on aircraft.

Acoustic mirrors

Even sound can be reflected using acoustic mirrors. This is an example of specular reflection of non electromagnetic waves.

Atomic mirrors

Atoms can be reflected using atomic mirrors. They also follow specular reflection.

Glossy paper

A glossy paper that are used in crafts and decorative purposes also reflect the light. This is also an specular reflection.

Scissors with fine finish

Most scissors are made with metallic alloys and plastics. Both materials when polished give a fine reflection.

Pupil of eye

Pupil of eye also reflects light, when we see other person in the eye then we can observe our reflection in it.

How does specular reflection works?

In above sections, we have discussed what specular reflection is. Now we will discuss how the specular reflection works.

When an incident ray of light strikes a polished surface (also called as specular surface), it gets reflected back with an exact angle at which the incident ray struck on the surface. A person standing in the path of reflected ray will be able to observe the image of the source object from where the incident ray was coming.

How to calculate specular reflection?

Specular reflection can be calculated with the help of Phong Model which was developed by computer graphics researcher Bui Toung.

The specular reflection is a dot product of two vectors. The formula is given below:

Specular reflection= V.R

Where, V is the viewing direction

R can be given by the formula given below-

R=2.(N.L)N-L

Where,

L is the incident light direction

Law of reflection

In optics, there three defined laws of reflection. They are given below-

  • The angles made by incident ray and reflected ray with the normal are same.
  • The incident ray, reflected rays and the normal all three exist in same plane.
  • Both the incident ray and reflected ray are on the different sides of normal.

Does specular reflection obey law of reflection?

Specular reflection obeys the law of reflection. It satisfies all the conditions that laws of reflection require. The incident ray makes an equal angle with the normal as reflected ray makes.

With that, reflected ray will be on one side of the normal and incident ray will be on the other side of normal. Then most importantly, all the three- normal, incident ray and reflected ray lie on the same plane. Hence, we can say that specular reflection obeys all three laws of reflection.

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