Diffraction is a process by virtue of which a system of waves spreads out after passing through narrow gaps. The system of waves includes sound waves, light waves, electromagnetic waves, water waves, etc. Diffraction, in general, is the bending of waves around a small aperture. The process of diffraction was first observed by Francesco Maria Grimaldi, an Italian mathematician and physicist. His work was officially published in the year 1665. Diffraction is quite a versatile process that can be seen in a lot of daily practices.
For instance, the following are some real-life examples of diffraction:
1. Compact Disk
Compact Disks are most susceptible to the process of diffraction. The surface of the compact disk is shiny and consists of a number of grooves. When light falls on the top of a CD, a part of it gets diffracted while some part of the light gets reflected. This is the reason why we see a rainbow-like pattern on a compact disk.
2. Hologram
Hologram, the word has been derived from two Greek words, ‘holo’ means whole, and ‘gram’ means a message. It is one fine technology that promises us an incredible future. Hologram basically makes use of diffraction to generate a 3D impression of the image. Different versions of the image get diffracted and reach the lens from multiple sides, all together forming an interference pattern. This pattern is then made to fall on the holographic plate. Finally, providing us with a 3-Dimensional experience.
3. Light entering a dark room
Suppose, there is a room with no light source, plus the light from the door is forbidden to enter the room as it is closed, and when someone opens the door partially, you can observe that the light gushes inside with a bend across the edges and around the corners of the door. The door acts as an obstacle in the path of light, therefore the light bends. This bending, undoubtedly, is known as diffraction.
4. Crepuscular Rays
You must have seen this breathtaking view for at least once in your life. These magnificent looking rays are known as crepuscular rays or God rays. When the light rays from the sun try to reach the ground but are blocked by the clouds, the light waves get diffracted and deviated. This deflection of light, due to the presence of a barrier in its normal pathway, is nothing but diffraction. The next time you see such a stunning view, you can share the reason behind it.
5. X-Ray Diffraction
In x-ray diffraction, the sample is kept in an instrument and is illuminated with x-rays. The x-ray tube and detector move in a synchronized motion, the observed signal is then recorded and studied. This phenomenon is most widely used in the determination of the distance between two consecutive atoms of an element. The process of X-Ray Diffraction is very important in meteorological, pharmaceutical, chemical, and other related industries as whenever the researchers come across some unidentified elements, they need to configure out the details about its structure, beginning with the alignment, distance, and other characteristics of its atoms.
6. Water passing from a small gap
The flowing water of a river when confronts a small slit, it tends to break its normal flow. The water waves undergo bends at the other side of the slit. This bending is yet another example of diffraction.
7. Solar/Lunar Corona
In meteorological terms, the term corona describes the ring of light around the sun or the moon that is formed when the sunlight or moonlight gets diffracted by small water vapours or ice crystals. The halo of the moon is known as the lunar corona and that of the sun is known as the solar corona.
8. Sound
If someone calls your name loudly, you are able to hear it. If they hide behind a tall tree and call your name with the same intensity, would you be able to hear that? The answer is yes, but how come the sound is not blocked even when a huge tree is present in its pathway. The reason being sound travels and reaches your ear through the process of diffraction.
9. Ring of light around the source
Look at any source of light around you right now, you may observe the light does not directly get transmitted in the forward direction, a small part of the light energy is diffracted around the source. This diffraction of light occurs due to the presence of dust and gaseous particles present nearby.
10. Signal Propagation
The process of diffraction is significantly used in long-distance radio signal propagation. Due to the curved surface of the earth and huge obstacles present on it, line of sight propagation for long-distance is not possible. Which is why we make use of multi-level diffraction for a signal to reach its destination. The signal keeps striking the obstacles while being amplified simultaneously with the help of boosters again and again till it reaches the destination. Diffraction is responsible for the phone calls you’re able to attend.
