Light is a form of energy that lies in the visible region of the electromagnetic spectrum (Light Spectrum). Outside of the visible spectrum, there are other electromagnetic wavelengths such as ultraviolet and infrared. Light covers a wide electromagnetic spectrum with the combination of these different wavelengths.
Light travels at a specific speed, approximately 299,792 km/sec in a vacuum. Light can propagate in vacuum, in air, in water, in transparent materials such as glass, and in many other media. Photons are produced as a result of charges vibrating in an electromagnetic field, and these photons provide the transport of light.
Light is used in many different applications, not only satisfying the sense of sight, but also playing an important role in communications, medicine, optics, photography, astronomy and many other fields.
It is an electromagnetic wave carried by the movement of particles called photons . Electromagnetic waves are energy carriers formed by the interaction of electric and magnetic fields. Light is a combination of electromagnetic waves with different wavelengths. The colors we perceive visually correspond to these different wavelengths. Light includes red, orange, yellow, green, blue, indigo and violet among the wavelengths in the visible spectrum.
Another important property of light is that it contains a property known as wave-nuclear duality. This property refers to the ability of light to exhibit both wave and particle properties. The quantum theory of light explains how light exhibits this duality.
The light spectrum is defined as a visual representation of specific wavelengths and frequencies within the electromagnetic spectrum. The electromagnetic spectrum represents a range of electromagnetic waves encompassing a wide range of energies.
Each wavelength or frequency range represents a specific energy level and the ability to influence specific physical phenomena.
The light spectrum includes different wavelengths, such as visible light, ultraviolet, infrared, microwaves, radio waves, x-rays, and gamma rays.
Gamma Rays:
They are characterized by their short wavelengths and high frequencies. Gamma rays typically result from changes in energy levels within atomic nuclei or nuclear reactions. Nuclear reactions can cause the emission of gamma rays at high energy levels.
They are used in astrophysics to study very distant and energetic astronomical events. Events such as explosive events in distant galaxies, flows of matter around black holes, and the collapse of stars can produce the intense energy emitted by gamma rays. Specially designed gamma telescopes are used to study high-energy astronomical phenomena.
Gamma rays are used in medicine to treat cancer and to control the quality of materials in industrial applications. Radiotherapy uses gamma rays to target cancer cells.
X-Rays:
X-rays are a type of very high-energy electromagnetic radiation located between ultraviolet and gamma rays on the electromagnetic spectrum. They have short wavelengths and high frequencies. These properties increase X-rays' ability to penetrate matter deeply and are therefore used in various applications in medicine, industry, research, and astronomy. However, excessive exposure poses health risks.
X-ray machines use X-rays to create images of bones, organs, and other tissues inside the body. They are also widely used in dentistry.
Ultraviolet (UV):
Also called ultraviolet, it is a type of light that is invisible to the naked eye.
UV-A (320-400 nm):
UVA is the longest wavelength ultraviolet ray.
A large portion of sunlight contains UVA. These wavelengths can cause skin aging and tanning.
Eyeglass lenses usually block some of the UVA rays.
UV-B (280-320 nm):
UVB is the medium-wavelength ultraviolet ray.
These rays can increase tanning by causing melanin production in the skin.
They can increase the risk of sunburn and skin cancer.
UV-C (100-280 nm):
UVC is the shortest wavelength ultraviolet ray.
They are generally not absorbed by the ozone layer in the Earth's atmosphere and do not reach the surface.
Visible Light Spectrum:
Contains the portion of the spectrum that can be perceived by humans. This region encompasses electromagnetic waves with wavelengths between 380 nm and 750 nm. The emission of colored light at these wavelengths gives rise to the colors of the rainbow.
Violet (Approximately 380-450 nm):
Violet light has the shortest wavelengths and the highest energy.
It is located in the inner part of the rainbow in the color spectrum.
Blue (450-495 nm):
Blue light encompasses wavelengths between violet and green.
The blue color band of the rainbow is the region following violet.
Green (495-570 nm):
Green light encompasses wavelengths between blue and yellow.
It is located in the middle region of the rainbow.
Yellow (570-590 nm):
Yellow light encompasses wavelengths between green and orange.
It is located after green in the rainbow's color order.
Orange (590-620 nm):
Orange light encompasses wavelengths between yellow and red.
It comes after yellow in the rainbow's color spectrum.
Red (620-750 nm):
Red light has the longest wavelengths and the lowest energy.
It is located at the outermost point of the rainbow's color spectrum.
Infrared (IR):
Wavelengths generally include electromagnetic waves between 750 nm and 1 millimeter (mm). This region encompasses heat energy, which is invisible to the naked eye but is emitted or absorbed by many objects and organisms. Infrared rays provide important technology used in various fields due to their properties in this region of the electromagnetic spectrum.
Microwave:
Wavelengths generally range from 1 mm to 1 m. Microwaves are used in many applications and represent a technology we frequently encounter in our daily lives.
Radio Waves:
Radio waves are a type of electromagnetic radiation that constitutes the lower frequency region of the electromagnetic spectrum. Radio waves typically have wavelengths ranging from one millimeter to several hundred meters. These long wavelengths are used for data transmission, communication, radio and television broadcasts, radar, remote sensing, and many other technological applications.
