1 Fiber Optics MULTIMODE VS. SINGLEMODE FIBER

2 Fiber Optics When we talk about fiber we refer to either multimode or singlemode fiber. We further clarify the types by their core and cladding size. The core and cladding numbers will be listed on the cable jackets………… When we talk about fiber we refer to either multimode or singlemode fiber. We further clarify the types by their core and cladding size. The core and cladding numbers will be listed on the cable jackets…………

3 Fiber Optics The standard core and cladding size for multimode fiber is 62.5/125 A new multimode standard (OM3) that uses an optimized laser transmissions system has a core and cladding size of 50/125. The standard core and cladding size for singlemode fiber is The standard core and cladding size for multimode fiber is 62.5/125 A new multimode standard (OM3) that uses an optimized laser transmissions system has a core and cladding size of 50/125. The standard core and cladding size for singlemode fiber is 8.3/125

4 Fiber Optics The 62.5/125um MM standard is color coded orange. The 50/125um MM standard is color coded aqua. The 8.3/125um SM standard is color coded yellow. The 62.5/125um MM standard is color coded orange. The 50/125um MM standard is color coded aqua. The 8.3/125um SM standard is color coded yellow.

5 Fiber Optics The terms multimode and singlemode refer to how light signals are transmitted through a fiber. Single mode fiber uses a single mode of transmitting data The data flows down a solid core of glass This glass is referred to as step index fiber The terms multimode and singlemode refer to how light signals are transmitted through a fiber. Single mode fiber uses a single mode of transmitting data The data flows down a solid core of glass This glass is referred to as step index fiber

6 Fiber Optics Multimode fiber utilizes multiple modes of transmitting data thru the glass The glass core is comprised of multiple layers of glass This type of glass core is called graded index Multimode fiber utilizes multiple modes of transmitting data thru the glass The glass core is comprised of multiple layers of glass This type of glass core is called graded index

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8 In graded index fiber the signal is sent down each layer of glass, allowing for multiple modes of transmission. The graded index of MM fiber is quoted as only one core size i.e. 62.5um or 50um both of which have multiple layers of glass. In graded index fiber the signal is sent down each layer of glass, allowing for multiple modes of transmission. The graded index of MM fiber is quoted as only one core size i.e. 62.5um or 50um both of which have multiple layers of glass.

9 Fiber Optics There is MM fiber with larger step index cores (solid glass cores) that are used for low speed LANs. We see this application in home theater systems that use fiber for audio, these are very short distance fibers that are typically used as a patch cord. The smaller the core the further the light can travel without as much light dispersion loss. There is MM fiber with larger step index cores (solid glass cores) that are used for low speed LANs. We see this application in home theater systems that use fiber for audio, these are very short distance fibers that are typically used as a patch cord. The smaller the core the further the light can travel without as much light dispersion loss.

10 Fiber Optics WHAT DO THE NUMBERS MEAN?

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14 Fiber Optics The cladding is the same size for all three fiber types at 125 microns (micro meter). When stripping fiber for termination remember that the cladding is not stripped off. 900um MM fiber has another layer which is the actual jacketing that will be color coded to indicate the fiber color code sequence The cladding is the same size for all three fiber types at 125 microns (micro meter). When stripping fiber for termination remember that the cladding is not stripped off. 900um MM fiber has another layer which is the actual jacketing that will be color coded to indicate the fiber color code sequence

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16 Fiber Optics SM fiber is 250um which is very thin, the buffer material is color coded which keeps the overall diameter small. MM mode fiber can also have a 250um buffer, this smaller sized fiber is normally found in outside plant cabling and many times under the same jacketing with SM fiber and would require a break out kit to facilitate terminations. SM fiber is 250um which is very thin, the buffer material is color coded which keeps the overall diameter small. MM mode fiber can also have a 250um buffer, this smaller sized fiber is normally found in outside plant cabling and many times under the same jacketing with SM fiber and would require a break out kit to facilitate terminations.

17 Fiber Optics The colors associated with multimode and singlemode mostly apply to the patch cords, though MC (metallic clad) cables will also be color coded to distinguish the different modes. What color is associated with singlemode? The colors associated with multimode and singlemode mostly apply to the patch cords, though MC (metallic clad) cables will also be color coded to distinguish the different modes. What color is associated with singlemode? YELLOW

18 Fiber Optics What color is associated with 62.5um MM fiber? What color is associated with 50um MM fiber? What color is associated with 62.5um MM fiber? What color is associated with 50um MM fiber? YELLOW AQUA

19 Fiber Optics Singlemode fiber uses lasers to transmit signals through the core, lasers in conjunction with the smaller core size allows the light to travel much further. The light will propagate down the fiber for 26km or 15.1 miles before the signal has to be repeated. Singlemode fiber uses lasers to transmit signals through the core, lasers in conjunction with the smaller core size allows the light to travel much further. The light will propagate down the fiber for 26km or 15.1 miles before the signal has to be repeated.

20 Fiber Optics Multimode uses LEDs to transmit light signals through the fiber core, this limits the distance that the light will travel. The maximum length of a MM cable run is 2000 meters. The LED light used is red and will not affect your eyes if you look directly at, with lasers the light is in a spectrum invisible to the human eye and can cause damage to your sight. Multimode uses LEDs to transmit light signals through the fiber core, this limits the distance that the light will travel. The maximum length of a MM cable run is 2000 meters. The LED light used is red and will not affect your eyes if you look directly at, with lasers the light is in a spectrum invisible to the human eye and can cause damage to your sight.