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Understanding Optical Sources in Fiber Optic Communication

This free online course covers the processes that takes place in fiber optic cables to enable optic communication.

Publisher: NPTEL
This free online course on Understanding Optical Sources in Fiber Optic Communication is an exciting course that introduces you to the multiple processes involved in optical communication. The different internal operations that take place in the fiber optic cable that makes communication so seamless, will be revealed. Additionally, you will learn what makes LEDs and laser diodes a preferred choice over other optical sources.
Understanding Optical Sources in Fiber Optic Communication
  • Duration

    3-4 Hours
  • Students

  • Accreditation






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Understanding Optical Sources in Fiber Optic Communication, is a free online course that seeks to enlighten learners on how optical sources in fiber optic communication works. In optical communications, there is a device that converts an electrical signal into an optical signal. It is important to note that the two most commonly used optical sources are light-emitting diodes (LEDs) and laser diodes. For fiber optics with glass fibers, light in the infrared region is used, which have wavelengths longer than visible light, generally around 850, 1300 and 1550 nm. Why do we use the infrared? Because the contracting of the fiber is far less at those wavelengths. In the course, you will discover the different optical sources used, specifically LED and Laser Diodes. LED is a directional light source, with the maximum emitted power in the direction perpendicular to the emitting surface. A semiconductor device, similar to a light-emitting diode in which a diode-pumped directly with electrical current can create lasing conditions at the diode's junction, will be discussed. Laser diodes are the most common type of lasers produced, with a wide range of uses that include fiber optic communications, barcode readers, laser pointers and light beam illumination.

Next, you will compare the major difference between lasers and LED's. Lasers are more powerful and operate at faster speeds than LED's, and they can also transmit light farther with fewer errors. A laser is also far more expensive than LED's. You will learn about the modulation bandwidth of LED's and what limits their bandwidth. You will also study how efficiently a device converts electrons to photons and allows them to escape, otherwise known as external quantum efficiency. This course gives you an understanding of the processes that take place between devices to enable optical communication to be successful. Fibre optic cables work by applying the basic principles of reflection and refraction. When light strikes a shiny or mirrored object, it bounces. When light travels between two substances that are of different thickness or density, it refracts, depending on the angle at which it strikes the substance. At a certain angle, light no longer travels between the substances but reflects into the original substance altogether. The boundary now acts as a mirror, keeping the light inside. This is called total internal reflection and is the foundation of the fiber optic cable.

Finally, the properties of fibre optics have allowed medical personnel to see places in the human body with greater ease and comfort to the patient. You may have seen plastic fibers carrying coloured lights in decorative applications. What you may not have been aware of is that real glass fiber optic cables are now the foundation of our communication and computer network systems. Many thousands of kilometres of installed fiber optic cables carry different types of information underground, through tunnels, building walls, ceilings, and many other places. Humanity enjoys the everyday benefits of optical communication when watching favourite shows, calling a friend via video call or even sitting around a computer or on a phone doing this course. These are all examples of optical communication. We are in a modernized era where technological development is increasing every day. Everything we have achieved so far is impressive and was unimaginable to earlier generations. What is yet to be achieved we cannot possibly fathom. Do you want to be a part of this exciting opportunity in an ever-changing world? Start this course today and take a step into this compelling world!

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