Unit 9 Exercise 1 Light sources
Unit 9. Exercise 1. Light Sources and Components – Definitions
1. Forward Biased LED – Semiconductor diode with a positive voltage applied to the p-region and a negative voltage to the n-region.
2. Incoherent Light – Light in which the electric and magnetic fields of photons are completely random in orientation. Incoherent light is typically emitted from light bulbs and LEDs.
3. Laser – Acronym for light amplification by stimulated emission of radiation. The laser produces a coherent source of light with a narrow beam and a narrow spectral bandwidth (about 2cm). Lasers in fiber optics are usually solid-state semiconductor types. Lasers are used to provide the high-powered, tightly controlled light wavelengths necessary for high-speed, long-distance optical fiber transmissions.
4. Output Pattern – LED and laser semiconductors used in fiber-optic light sources are packaged to couple as much light as possible into the core of the optical fiber. The output pattern, or NA of the light source directly relates to the energy coupled into the core of the optical fiber.
5. Ouput Power – This power of light sources used in fiber-optic communication systems varies dramatically depending on the application. LEDs are typically designed to support transmission distances of up to 2km while laser light achieves distances in excess of 80km. Laser optical power output levels can exceed LED optical output power levels by more than 20dB.
6. Modulation Speed – One factor that can limit the performance/bandwidth of a fiber-optic communication system via the light source.
7. Core Diameter Mismatch – Occurs when there is a difference in the core diameters of the two optical fibers. A los may occur when the core diameter of the transmitting optical fiber is greater than the core diameter of the receiving optical fiber.
8. Current – Flow of electrons in a conductor.
9. PIN Photodiode – works like a PN photodiode; however, it is manufactured to offer better
1. Forward Biased LED – Semiconductor diode with a positive voltage applied to the p-region and a negative voltage to the n-region.
2. Incoherent Light – Light in which the electric and magnetic fields of photons are completely random in orientation. Incoherent light is typically emitted from light bulbs and LEDs.
3. Laser – Acronym for light amplification by stimulated emission of radiation. The laser produces a coherent source of light with a narrow beam and a narrow spectral bandwidth (about 2cm). Lasers in fiber optics are usually solid-state semiconductor types. Lasers are used to provide the high-powered, tightly controlled light wavelengths necessary for high-speed, long-distance optical fiber transmissions.
4. Output Pattern – LED and laser semiconductors used in fiber-optic light sources are packaged to couple as much light as possible into the core of the optical fiber. The output pattern, or NA of the light source directly relates to the energy coupled into the core of the optical fiber.
5. Ouput Power – This power of light sources used in fiber-optic communication systems varies dramatically depending on the application. LEDs are typically designed to support transmission distances of up to 2km while laser light achieves distances in excess of 80km. Laser optical power output levels can exceed LED optical output power levels by more than 20dB.
6. Modulation Speed – One factor that can limit the performance/bandwidth of a fiber-optic communication system via the light source.
7. Core Diameter Mismatch – Occurs when there is a difference in the core diameters of the two optical fibers. A los may occur when the core diameter of the transmitting optical fiber is greater than the core diameter of the receiving optical fiber.
8. Current – Flow of electrons in a conductor.
9. PIN Photodiode – works like a PN photodiode; however, it is manufactured to offer better