A light source is defined as an object that is capable of emitting light radiations or energy into the environment. Light sources can be broadly classified into two categories, namely natural sources of light and artificial or man-made sources of light. The objects that are capable of emitting light of their own are known as luminous objects. This means that all the sources of light are luminous objects. The sources of light that are constructed artificially and are capable of emitting light of their own are typically known as artificial sources of light. The properties of light radiations obtained from artificial sources of light such as intensity, speed of propagation, brightness, contrast, etc. can be varied or controlled externally up to a certain level or magnitude.
Examples of Artificial Sources of Light
The artificial sources of light are manufactured in a variety of shapes, sizes, and types. Some of the most common artificial sources of light present around us are listed below:
1. Light Bulbs
Electric light bulbs, tube lights, lamps, etc. are some of the sources of light that fall under the category of artificial sources. Such gadgets are manufactured artificially and are typically powered with the help of electrical energy. The operation of such devices can be varied or controlled externally up to a certain level.
Torches are one of the prominent examples of the artificial sources of light present around us. The operation of a torch is quite similar to that of light bulbs and other similar pieces of equipment. The only difference is that the torches are equipped with a DC source of energy such as a battery, etc.
A lighter typically makes use of fuel and sparking action of elements to produce light energy into the environment. This means that a lighter is yet another example of the artificial sources of light present around us.
Candles are yet another example of manmade or artificial sources of energy. A candle typically consists of a wick made up of fibre that is immersed in between a wax structure. When the wick of the candle is lighted, the wax tends to melt and light energy is radiated into the environment.
Fireworks typically make use of chemical energy to produce light radiations into the environment, hence they are considered to be one of the prominent examples of artificial light sources.
LASER is abbreviated as light amplification by spontaneous emission of radiations. It is a beam of highly concentrated energized photons of energy. LASER serves to be one of the prime examples of artificial sources of light.
Research shows that the fire was discovered during the early stone age i.e., about 1.7 to 2.0 million years ago. The fire was discovered by humans and is created externally, which is why it is known as one of the most common artificial sources of light.
8. Glow Sticks
Glow sticks are man-made sources of light that usually make use of chemical compounds, namely hydrogen peroxide and fluorescent dyes to produce luminescence. The glow sticks are unable to produce light until the chemicals get mixed with each other. The mixing of chemicals is performed by shaking the sticks. The conversion of the potential energy contained by the chemicals into kinetic energy results in the production of visible light.