History of Light

Shweta Katheria

Mar 9, 2019 . 2 min read

This is 5th to 3rd BC era of ancient Greece. Many researchers through the ages have always wondered what is Light? That’s why optics has also been the oldest discipline along with mechanics. Here is the description of how research has evolved with time.

“The essence of light is white light.
Colors are made up of a mixture
of lightness and darkness.”

In the back, around 4th B.C. at the time of Aristotle laid the foundation of optics in Ancient Greece. And then Euclid (330–275 B.C.) summarized fundamental knowledge of optics, such as reflection, diffusion, and vision, into a book called “Optics”. At that time they described light as the white light and colors are made of lightness and darkness.

10th-11th Centuries

light

Photo by Todd Diemer on Unsplash

“Why does the moon appear larger near
the horizon than it does
when higher up in the sky ?”

At this time interval, observation on light reflection and refraction through mirrors and lenses, visual perception and light from the moon and stars, and the structure of space are made.

17th-18th Centuries

light

Source : https://pixabay.com/en/refraction-prism-optics-150853/

 

“Light is comprised of colored particles.”

This was the time of sir Isaac Newton (Newton Baba) when he started experimenting on technologies like lenses, prisms, mirrors, telescopes, microscopes, and optical (mirror/lens) polishing. In a paper, he announced, “new theory on light and color” in which he proclaimed that “light is a mixture of various colors having different refractive index” rather than “the pure white (sunlight)” proposed by Aristotle and demonstrated prism experiment. Here laid the foundation of light particle theory.

“Light is a wave.”

During this same era, Christiaan Huygens published a paper on light advocating his theory that light is a wave or wavefront. He utilized this theory of light as a wave to explain light reflection and refraction phenomenon. But since he was opposing the theory of Newton (a great discoverer and scientist) that was the matter of heated discussion that time.

light

Source : https://sites.ualberta.ca/~pogosyan/teaching/PHYS_130/FALL_2010/lectures/lect23/lecture23.html

18th-19th Centuries :

“Proof of the wave theory of light”

light

Image Source : sureden  

Here comes the entry of Thomas Young(same person who worked on elasticity and has fundamental constant Young’s Modulus on his name). he showed that when light coming from a point light source is shined onto two pinholes, interference fringes can be observed on a screen an appropriate distance away (Young’s double slit Experiment) and advocated his theory that light behaves like a wave.

“Predicted the existence of electromagnetic waves”

light

Image Source : https://pixabay.com/en/electromagnetic-waves-wave-length-1526374/

 

Maxwell predicted the existence of electromagnetic waves, the fact that electromagnetic waves propagate at the same speed as light, and as horizontal waves. And we can see different types of light on this Electromagnetic spectrum.

light

Source: wikipedia  

20th century :

“Light is a photon”

light

source Image Source : tutorVista

Albert Einstein’s photoelectric experiment again changed the direction of Modern Physics. This experiment shows that light is made up of particles called photons, which earned him the Nobel Prize in physics.

The photon has many mysterious physical properties such as possessing the dual properties of a wave and a particle. Revealing facts of these properties may lead us to use light more effectively than ever before. The photon is a substance that is seen as the key to the origins of space and life. For human beings, the history of light and optics research may have only just begun.

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