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A brief note on Huygens Principle

Huygen's principles state that every point on a wavefront in itself, a source of spherical wavelets and sum of these spherical wavelets forms the wavefronts.

The spherical wavelets refer to the wave that propagates through space like the ripples in the water and the sound in the air. The locus point that travels some distance during a fixed time interval is also called the wavefront. After the primary wavefront is created, a secondary wavefront is formed from the primary wavefront. The ideas as well as the concepts of spherical wavelets are completely based on Huygen’s principles. Huygen’s concepts also proved the refraction and the reflection of light. When the light passes through the aperture, every point from the wave point within the aperture can also be viewed as a source of creating a circular wave.

Description of the Spherical Wavelets in Huygen’s Principle

The sum of the spherical wavelets always forms the wavefront. The principles of Huygen are one of the most important principles that help to analyse the key concepts of the wavefront. The principles also state the fact that the secondary sources always start making their own wavelets. All these sources are similar to the primary sources. Moreover, a secondary wavefront is also generated from each point of the primary wavefront. The ideas and the principles of Huygen also include the reflection and refraction of light. It also includes the interference of light and the concepts of the diffraction of light. All the rays are always perpendicular to the wavefront. The types of wavefronts based on the principles of Huygen include the plane wavefront, spherical wavefront and cylindrical wavefront. The cylindrical wavefront is formed when the source of the light on the linear position. 

Discussion on Differences between Spherical Wavelets and Secondary Wavelets

The spherical wavelets together form a wavelet. Huygen’s principles are used to provide a quantitative explanation of both rectangular as well as spherical wave propagation. The laws of reflection and refraction are completely based on the principles and the concepts of Huygen. The angle of incidence is always equal to the reflecting angle. The ideas and the concepts of the angle of incidence and reflection angle are widely described in the first laws of reflection. The secondary wavelets are the direct results of the primary wavelets. The differences between the spherical wavelets and the secondary wavelets lie in their forms. The Secondary Wavelets originate from the primary wavelets and follow the principles of Huygen. On the other hand, the spherical wavelets always take the shape of a sphere. 

The Key Features of Optical Phenomena

Optical phenomena are any observable events that are caused by the interaction of light as well as matter. Moreover, the optical phenomena also coincide with the quantum phenomena. The common optical phenomena happen due to the interaction of light from the sun and the moon. The key optical phenomena in nature include reflection, refraction, the diffusion of the rays of sunlight and scattering. The ideas and the concepts of the optical phenomenon are completely based on the principles of Huygen. This type of phenomenon is produced by the reflection and the refraction of light. The interaction of matter and light causes optical phenomena in nature. It is an interesting topic of optics. The fact that colours appear in the sky’s the direct result of the optical phenomena. 


Conclusively, various components related to the spherical wavelets and secondary wavelets are demonstrated in relation to Huygen’s Principle. The key concepts about wavefront can also be knowledgeable from this principle given by Huygen in 1678. It has been known from this principle that all the areas inside a wavefront can become a secondary source that can emit wavelets. An overview of optical phenomena has also been given to understand its relationship with the principle given by Huygen. Therefore, various concepts related to light are discussed in this process that include refraction and reflection. Seven principles can be seen in this context that gives an overview of the nature of light waves.


Frequently asked questions

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What are spherical wavelets in Huygen’s principle?

Ans.The spherical wavelets refer to the fact that every point on a wavefront is in itself the source of the spherical wavelets. However, in other w...Read full

What are the key features of Secondary Wavelets?

Ans. The secondary wavelets always originate from the primary wavelets. The points related to the spherical wavelets are also equidistant from the ...Read full

What are the key factors of Secondary Wavelets?

Ans. The secondary wavelets are completely related to the primary wavelets. They also start making their own wavelets and these wavelets are comple...Read full

What are the different types of Optical Phenomena?

Ans. There are different types of optical phenomena usually observed in nature. The key types of optical phen...Read full