How lighting evolved over the years?

Evolution of Lights

Lighting today has become one of the essential needs for our daily life. The advent of energy efficient and reliable lighting at home and workplaces has been and continues to be a major part of our life. These days, we don’t expect a functional building without a light.With lighting playing a huge role, did you ever wonder how lighting has come into existence and evolved?”

Let’s see how it all started and became a daily part of our life.

When we think of lighting, it’s important to think of these 3 things: the fuel source, the luminary and the technology used to produce this lighting. Using these three things, let’s see how it happened to the modern day innovation of 21st century LEDs.

Natural Lighting: The most important source of lighting and now the source of energy is the sun. The architecture also used to be in a way to take advantage of with opening in the middle. If you have observed our old homes and homes which even exist today in most villages, they do have verandas in the middle of homes to have proper daylight in the house.

Torches, candles, and lamps: Illuminating Engineering society says “The first man-made attempt on lighting occurred about 70,000 years. The first lamp was invented made of a shell, hollowed-out rock, or another similar non-flammable object which was filled with a combustible material (probably dried grass or wood), sprinkled with animal fat (the original lighter fluid) and ignited”. As you can guess, this was used for cooking as well as torches to travel in the dark.

Building mounted and handheld torches improved well beyond their initial start but the basic principle remained the same: the fuel source is some type of oil, wax, or combustible material surrounded by non-flammable material. As you might expect, technology like ventilation (e.g. tubes and chimneys) vastly improved the ability to effectively use fire for lighting. Perhaps the most important advancement, however, was the introduction of the wick to make candles. These were dated back to 4th century B.C. in Egypt according to author Patricia Telesco. Also, societies in Asia were also making wax out of whale skin as early as 200 B.C.

Then entered Gas lamps. They were developed in the late 18th century in the west and was slowly used in India in the 19th century as Gas street lamps. Different types of gases like butane, propane, hydrogen were used to lit this. I still remember my Grandma during my childhood days, showing how to lit this lamp using kerosene.

Electric lamp was first created by Humphrey Davey which we now refer to as Arc lighting.

But the need for a permanent source of lighting kept many innovators pushing for new advancements. Thus, came incandescent bulb by Thomas Alva Edison. His work was also on developing the infrastructure required to power such a bulb which was like a magic in those days. His first successful prototype burned for 13 and half hours. Then, he further developed it using carbonized bamboo filament which ran for 1200 hours.

Incandescent bulbs went on to dominate till the entry of fluorescent bulbs in the late 90's in India. I always get confused to differentiate between fluorescent and incandescent lights. If that’s the same case with you too, you can differentiate them simply by their working. Fluorescent as the name suggests, produce the light by exciting the gas and causing it to glow. Incandescent bulbs produce light by heating a metallic filament inside to radiate light.

To say, fluorescent is one type of high-intensity discharge bulbs (HID). There are some other commercially successful HID lights of the 20th century- mercury vapour, metal halide and high-pressure sodium. All of these lamps are the same type of technology in that they operate by sending an electrical current between two metal electrodes and through a glass tube filled with inert gas resulting in the emission of visible light.

Now comes the LED lighting which is quite different in working as well as efficiency from the above. The first LEDs were red. This wasn’t an aesthetic choice. LEDs are made by building layers of semiconductor crystals on a wafer. As the layers are added, dopants are added to determine the colour of the LED.

New processes have delivered a rainbow of available LED colours, making them suitable for far more than battery indicators and warning lights. But for the first 10 years of their existence, LEDs were red. As relatively inexpensive, low-power LEDs began replacing incandescent bulbs in electronics; prices for those electronics fell into a much more consumer-friendly range. Modern LEDs have a lifespan of 4–5 times the fluorescent lighting. These standards are making it the best in business.

Nowadays, I see them being used in the tier2 and tier3 cities too. With people able to afford these LED lights at a price in the range of CFLs and government stepping in to make India LED powerhouse, I see a bright future for India becoming energy efficient.

What’s your view in regard to this? Do you feel the same? Please let us know your views in comment section.

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