ºÝºÝߣshows by User: fiberoptics4sale / http://www.slideshare.net/images/logo.gif ºÝºÝߣshows by User: fiberoptics4sale / Fri, 10 May 2013 13:57:10 GMT ºÝºÝߣShare feed for ºÝºÝߣshows by User: fiberoptics4sale What is l co s based wavelength selective switch /slideshow/what-is-l-co-s-based-wavelength-selective-switch/20940416 whatislcosbasedwavelengthselectiveswitch-130510135710-phpapp02
Wavelength selective switch is becoming the central part of ROADM (reconfigurable optical add drop multiplexer). In a WSS, different wavelength channels from the input fiber can be independently switched to different output ports, as shown in the right side picture. The left side picture shows an actual WSS product from Finisar. This illustration shows a generic design of WSS. This optical principle is used on many different WSS designs, such as LCoS or MEMS based WSS switches. Multiple wavelengths come in from the input port. The input port is one port among the fiber array. The fiber array is in the direction of perpendicular to the screen, in other words, the fiber array is in and out of the screen, that is why you only see one port shown in the picture. The light from the input port is first expanded and collimated by the collimation optics. Then the light is projected onto the dispersive element. In a LCoS based WSS, this dispersive element is a conventional grating. The purpose of the dispersive element is to spatially separate these multiple wavelengths. With a conventional grating, the wavelengths are separated into different angles. Blue to the top, green in the middle, and red to the bottom. These lights are still collimated, so next they are focused by the focusing optics and projected onto the switching element. The purpose of the switching element is to direct different wavelengths to different output ports. In a LCoS based WSS, this switching element is a LCoS chip. This time, the switching element directs lights to different perpendicular angles, in other words, in the fiber array’s direction which is perpendicular to the screen. So when the lights trace back, they are focused into different output ports, depending on the switched angle by the switching element. ]]>
Wavelength selective switch is becoming the central part of ROADM (reconfigurable optical add drop multiplexer). In a WSS, different wavelength channels from the input fiber can be independently switched to different output ports, as shown in the right side picture. The left side picture shows an actual WSS product from Finisar. This illustration shows a generic design of WSS. This optical principle is used on many different WSS designs, such as LCoS or MEMS based WSS switches. Multiple wavelengths come in from the input port. The input port is one port among the fiber array. The fiber array is in the direction of perpendicular to the screen, in other words, the fiber array is in and out of the screen, that is why you only see one port shown in the picture. The light from the input port is first expanded and collimated by the collimation optics. Then the light is projected onto the dispersive element. In a LCoS based WSS, this dispersive element is a conventional grating. The purpose of the dispersive element is to spatially separate these multiple wavelengths. With a conventional grating, the wavelengths are separated into different angles. Blue to the top, green in the middle, and red to the bottom. These lights are still collimated, so next they are focused by the focusing optics and projected onto the switching element. The purpose of the switching element is to direct different wavelengths to different output ports. In a LCoS based WSS, this switching element is a LCoS chip. This time, the switching element directs lights to different perpendicular angles, in other words, in the fiber array’s direction which is perpendicular to the screen. So when the lights trace back, they are focused into different output ports, depending on the switched angle by the switching element. ]]> Fri, 10 May 2013 13:57:10 GMT /slideshow/what-is-l-co-s-based-wavelength-selective-switch/20940416 fiberoptics4sale@slideshare.net(fiberoptics4sale) What is l co s based wavelength selective switch fiberoptics4sale Wavelength selective switch is becoming the central part of ROADM (reconfigurable optical add drop multiplexer). In a WSS, different wavelength channels from the input fiber can be independently switched to different output ports, as shown in the right side picture. The left side picture shows an actual WSS product from Finisar. This illustration shows a generic design of WSS. This optical principle is used on many different WSS designs, such as LCoS or MEMS based WSS switches. Multiple wavelengths come in from the input port. The input port is one port among the fiber array. The fiber array is in the direction of perpendicular to the screen, in other words, the fiber array is in and out of the screen, that is why you only see one port shown in the picture. The light from the input port is first expanded and collimated by the collimation optics. Then the light is projected onto the dispersive element. In a LCoS based WSS, this dispersive element is a conventional grating. The purpose of the dispersive element is to spatially separate these multiple wavelengths. With a conventional grating, the wavelengths are separated into different angles. Blue to the top, green in the middle, and red to the bottom. These lights are still collimated, so next they are focused by the focusing optics and projected onto the switching element. The purpose of the switching element is to direct different wavelengths to different output ports. In a LCoS based WSS, this switching element is a LCoS chip. This time, the switching element directs lights to different perpendicular angles, in other words, in the fiber array’s direction which is perpendicular to the screen. So when the lights trace back, they are focused into different output ports, depending on the switched angle by the switching element. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/whatislcosbasedwavelengthselectiveswitch-130510135710-phpapp02-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Wavelength selective switch is becoming the central part of ROADM (reconfigurable optical add drop multiplexer). In a WSS, different wavelength channels from the input fiber can be independently switched to different output ports, as shown in the right side picture. The left side picture shows an actual WSS product from Finisar. This illustration shows a generic design of WSS. This optical principle is used on many different WSS designs, such as LCoS or MEMS based WSS switches. Multiple wavelengths come in from the input port. The input port is one port among the fiber array. The fiber array is in the direction of perpendicular to the screen, in other words, the fiber array is in and out of the screen, that is why you only see one port shown in the picture. The light from the input port is first expanded and collimated by the collimation optics. Then the light is projected onto the dispersive element. In a LCoS based WSS, this dispersive element is a conventional grating. The purpose of the dispersive element is to spatially separate these multiple wavelengths. With a conventional grating, the wavelengths are separated into different angles. Blue to the top, green in the middle, and red to the bottom. These lights are still collimated, so next they are focused by the focusing optics and projected onto the switching element. The purpose of the switching element is to direct different wavelengths to different output ports. In a LCoS based WSS, this switching element is a LCoS chip. This time, the switching element directs lights to different perpendicular angles, in other words, in the fiber array’s direction which is perpendicular to the screen. So when the lights trace back, they are focused into different output ports, depending on the switched angle by the switching element.
What is l co s based wavelength selective switch from FOSCO Fiber Optics
]]> 4330 6 https://cdn.slidesharecdn.com/ss_thumbnails/whatislcosbasedwavelengthselectiveswitch-130510135710-phpapp02-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 What is 16 qam modulation /slideshow/what-is-16-qam-modulation/19974406 whatis16qammodulation-130425131517-phpapp01
In this video, I will explain what is QAM modulation and what is 16QAM. QAM Stands for Quadrature Amplitude Modulation. QAM is both an analog and a digital modulation method. But here, we are only talking about QAM as a digital modulation. Quadrature means that two carrier waves are being used, one sine wave and one cosine wave. These two waves are out of phase with each other by 90°, this is called quadrature. At the receiving end, the sine and cosine wave can be decoded independently, this means that by using both a sine wave and a cosine wave, the communication channel's capacity is doubled comparing to using only one sine or one cosine wave. That is why quadrature is such a popular technique for digital modulation. QAM modulation is a combination of Amplitude Shift Keying and Phase Shift Keying, both carrier wave is modulated by changing both its amplitude and phase. As shown in this 8QAM waveform, the top is the sine wave carrier, for bit 000, the sin wave has a phase shift of 0°, and an amplitude of 2. While for bit 110, the phase shift is 180°, and the amplitude now is 1. So both phase and amplitude are changed. In 16QAM, the input binary data is combined into groups of 4 bits called QUADBITS. As shown in this picture, the I and I' bits are sent to the sine wave modulation path, and the Q and Q' bits are sent to the cosine wave path. Since the bits are split and sent in parallel, so the symbol rate has been reduced to a quarter of the input binary bit rate. If the input binary data rate is 100 Gbps, then the symbol rate is reduced to only 25 Gbaud/second. This is the reason why 16QAM is under hot research for 100Gbps fiber optic communication. The I and Q bits control the carrier wave's phase shift, if the bit is 0, then the phase shift is 180°, if the bit is 1, then the phase shift is 0°. The I' and Q' bits control the carrier wave's amplitude, if bit is 0, then the amplitude is 0.22 volt, if the bit is 1, then the amplitude is 0.821 volt. So each pair of bits has 4 different outputs. Then they are added up at the linear summer. 4X4 is 16, so there is a total of 16 different combinations at the output, that is why this is called 16QAM. This illustration shows an example of how the QUADBIT 0000 is modulated onto the carrier waves. Here I and I' is 00, so the output is -0.22 Volt at the 2-to-4-level converter, when timed with the sine wave carrier, we get -0.22sin(2πfct), here fc is the carrier wave's frequency. QQ' is also 00, so the other carrier wave output is -0.22cos(2πfct). Here is the proof that quadbit 0000 is modulated as a sine wave with an amplitude of 0.311volt and a phase shift of -135°. You can now pause for a moment to study the proof. This list shows the 16QAM modulation output with different amplitude and phase change for all 16 quadbits. On the right side is the constellation diagram which shows the positions of these quadbits on a I-Q diagram. You can visit FO4SALE.com f]]>
In this video, I will explain what is QAM modulation and what is 16QAM. QAM Stands for Quadrature Amplitude Modulation. QAM is both an analog and a digital modulation method. But here, we are only talking about QAM as a digital modulation. Quadrature means that two carrier waves are being used, one sine wave and one cosine wave. These two waves are out of phase with each other by 90°, this is called quadrature. At the receiving end, the sine and cosine wave can be decoded independently, this means that by using both a sine wave and a cosine wave, the communication channel's capacity is doubled comparing to using only one sine or one cosine wave. That is why quadrature is such a popular technique for digital modulation. QAM modulation is a combination of Amplitude Shift Keying and Phase Shift Keying, both carrier wave is modulated by changing both its amplitude and phase. As shown in this 8QAM waveform, the top is the sine wave carrier, for bit 000, the sin wave has a phase shift of 0°, and an amplitude of 2. While for bit 110, the phase shift is 180°, and the amplitude now is 1. So both phase and amplitude are changed. In 16QAM, the input binary data is combined into groups of 4 bits called QUADBITS. As shown in this picture, the I and I' bits are sent to the sine wave modulation path, and the Q and Q' bits are sent to the cosine wave path. Since the bits are split and sent in parallel, so the symbol rate has been reduced to a quarter of the input binary bit rate. If the input binary data rate is 100 Gbps, then the symbol rate is reduced to only 25 Gbaud/second. This is the reason why 16QAM is under hot research for 100Gbps fiber optic communication. The I and Q bits control the carrier wave's phase shift, if the bit is 0, then the phase shift is 180°, if the bit is 1, then the phase shift is 0°. The I' and Q' bits control the carrier wave's amplitude, if bit is 0, then the amplitude is 0.22 volt, if the bit is 1, then the amplitude is 0.821 volt. So each pair of bits has 4 different outputs. Then they are added up at the linear summer. 4X4 is 16, so there is a total of 16 different combinations at the output, that is why this is called 16QAM. This illustration shows an example of how the QUADBIT 0000 is modulated onto the carrier waves. Here I and I' is 00, so the output is -0.22 Volt at the 2-to-4-level converter, when timed with the sine wave carrier, we get -0.22sin(2πfct), here fc is the carrier wave's frequency. QQ' is also 00, so the other carrier wave output is -0.22cos(2πfct). Here is the proof that quadbit 0000 is modulated as a sine wave with an amplitude of 0.311volt and a phase shift of -135°. You can now pause for a moment to study the proof. This list shows the 16QAM modulation output with different amplitude and phase change for all 16 quadbits. On the right side is the constellation diagram which shows the positions of these quadbits on a I-Q diagram. You can visit FO4SALE.com f]]> Thu, 25 Apr 2013 13:15:17 GMT /slideshow/what-is-16-qam-modulation/19974406 fiberoptics4sale@slideshare.net(fiberoptics4sale) What is 16 qam modulation fiberoptics4sale In this video, I will explain what is QAM modulation and what is 16QAM. QAM Stands for Quadrature Amplitude Modulation. QAM is both an analog and a digital modulation method. But here, we are only talking about QAM as a digital modulation. Quadrature means that two carrier waves are being used, one sine wave and one cosine wave. These two waves are out of phase with each other by 90°, this is called quadrature. At the receiving end, the sine and cosine wave can be decoded independently, this means that by using both a sine wave and a cosine wave, the communication channel's capacity is doubled comparing to using only one sine or one cosine wave. That is why quadrature is such a popular technique for digital modulation. QAM modulation is a combination of Amplitude Shift Keying and Phase Shift Keying, both carrier wave is modulated by changing both its amplitude and phase. As shown in this 8QAM waveform, the top is the sine wave carrier, for bit 000, the sin wave has a phase shift of 0°, and an amplitude of 2. While for bit 110, the phase shift is 180°, and the amplitude now is 1. So both phase and amplitude are changed. In 16QAM, the input binary data is combined into groups of 4 bits called QUADBITS. As shown in this picture, the I and I' bits are sent to the sine wave modulation path, and the Q and Q' bits are sent to the cosine wave path. Since the bits are split and sent in parallel, so the symbol rate has been reduced to a quarter of the input binary bit rate. If the input binary data rate is 100 Gbps, then the symbol rate is reduced to only 25 Gbaud/second. This is the reason why 16QAM is under hot research for 100Gbps fiber optic communication. The I and Q bits control the carrier wave's phase shift, if the bit is 0, then the phase shift is 180°, if the bit is 1, then the phase shift is 0°. The I' and Q' bits control the carrier wave's amplitude, if bit is 0, then the amplitude is 0.22 volt, if the bit is 1, then the amplitude is 0.821 volt. So each pair of bits has 4 different outputs. Then they are added up at the linear summer. 4X4 is 16, so there is a total of 16 different combinations at the output, that is why this is called 16QAM. This illustration shows an example of how the QUADBIT 0000 is modulated onto the carrier waves. Here I and I' is 00, so the output is -0.22 Volt at the 2-to-4-level converter, when timed with the sine wave carrier, we get -0.22sin(2πfct), here fc is the carrier wave's frequency. QQ' is also 00, so the other carrier wave output is -0.22cos(2πfct). Here is the proof that quadbit 0000 is modulated as a sine wave with an amplitude of 0.311volt and a phase shift of -135°. You can now pause for a moment to study the proof. This list shows the 16QAM modulation output with different amplitude and phase change for all 16 quadbits. On the right side is the constellation diagram which shows the positions of these quadbits on a I-Q diagram. You can visit FO4SALE.com f <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/whatis16qammodulation-130425131517-phpapp01-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> In this video, I will explain what is QAM modulation and what is 16QAM. QAM Stands for Quadrature Amplitude Modulation. QAM is both an analog and a digital modulation method. But here, we are only talking about QAM as a digital modulation. Quadrature means that two carrier waves are being used, one sine wave and one cosine wave. These two waves are out of phase with each other by 90°, this is called quadrature. At the receiving end, the sine and cosine wave can be decoded independently, this means that by using both a sine wave and a cosine wave, the communication channel&#39;s capacity is doubled comparing to using only one sine or one cosine wave. That is why quadrature is such a popular technique for digital modulation. QAM modulation is a combination of Amplitude Shift Keying and Phase Shift Keying, both carrier wave is modulated by changing both its amplitude and phase. As shown in this 8QAM waveform, the top is the sine wave carrier, for bit 000, the sin wave has a phase shift of 0°, and an amplitude of 2. While for bit 110, the phase shift is 180°, and the amplitude now is 1. So both phase and amplitude are changed. In 16QAM, the input binary data is combined into groups of 4 bits called QUADBITS. As shown in this picture, the I and I&#39; bits are sent to the sine wave modulation path, and the Q and Q&#39; bits are sent to the cosine wave path. Since the bits are split and sent in parallel, so the symbol rate has been reduced to a quarter of the input binary bit rate. If the input binary data rate is 100 Gbps, then the symbol rate is reduced to only 25 Gbaud/second. This is the reason why 16QAM is under hot research for 100Gbps fiber optic communication. The I and Q bits control the carrier wave&#39;s phase shift, if the bit is 0, then the phase shift is 180°, if the bit is 1, then the phase shift is 0°. The I&#39; and Q&#39; bits control the carrier wave&#39;s amplitude, if bit is 0, then the amplitude is 0.22 volt, if the bit is 1, then the amplitude is 0.821 volt. So each pair of bits has 4 different outputs. Then they are added up at the linear summer. 4X4 is 16, so there is a total of 16 different combinations at the output, that is why this is called 16QAM. This illustration shows an example of how the QUADBIT 0000 is modulated onto the carrier waves. Here I and I&#39; is 00, so the output is -0.22 Volt at the 2-to-4-level converter, when timed with the sine wave carrier, we get -0.22sin(2πfct), here fc is the carrier wave&#39;s frequency. QQ&#39; is also 00, so the other carrier wave output is -0.22cos(2πfct). Here is the proof that quadbit 0000 is modulated as a sine wave with an amplitude of 0.311volt and a phase shift of -135°. You can now pause for a moment to study the proof. This list shows the 16QAM modulation output with different amplitude and phase change for all 16 quadbits. On the right side is the constellation diagram which shows the positions of these quadbits on a I-Q diagram. You can visit FO4SALE.com f
What is 16 qam modulation from FOSCO Fiber Optics
]]> 26626 10 https://cdn.slidesharecdn.com/ss_thumbnails/whatis16qammodulation-130425131517-phpapp01-thumbnail.jpg?width=120&height=120&fit=bounds presentation White http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 What is fiber optic /slideshow/what-is-fiber-optic/19971996 whatisfiberoptic-130425122050-phpapp01
So how is light guided and travels inside the fiber? This video shows a beam of light that travels inside a water stream by total internal reflection. Optical fibers work the same way. So let's take a look. A glass fiber has a cylindrical structure and is composed of three layers. At the center is the core, core has higher refractive index. Outside of core is the cladding layer. Cladding layer has lower refractive index than the core. The third layer is a plastic buffer coating. This buffer coating doesn't affect the fiber's optical performance, it is there for mechanical protection only. The right picture shows how light is coupled into the fiber's core and bounced back and forth in the core and travels along the fiber. The core and cladding layers are all based on fused silica which is a type of glass. But this fused silica is extremely clear, with almost no impurities. This transparency is extremely important, so that the light can travel for a very long distance, such as hundreds of kilometers with minimum loss. This makes trans-Pacific and trans-continent fiber optic communications possible. Here comes the question. Why doesn't the light leak out of the fiber? That is why we have to explain the phenomenon of total internal reflection. The left picture shows Snell's the law which guides how light travels at the interface of the core and cladding. The core has a higher refractive index n = 1.5. The cladding has a lower refractive index n = 1.4. When light incidents at the interface between the core and cladding at different angles, some power is reflected back, and some power enters into the cladding which is refracted. But when we increase the incident angle to greater than a critical angle theta c, no more light enters into the cladding, all light is reflected back into the core. This phenomenon is called Total Internal Reflection. Here total means 100% of the power is reflected back into the core. The manufacturing of glass fibers go through two steps. In the first step a preform is made. This preform has exactly the same proportion of core and cladding as final fiber product, but in a much bigger size. It looks like a thick glass rod, as shown in the bottom picture. Then the preform is hanged at the top of a fiber drawing tower. The tower is a couple of stories tall as shown in the right picture. The preform is heated by a furnace which softens the glass. The softened glass drips and pulled downward by gravity. A diameter monitor carefully monitors the fiber's diameter, which usually is 125um. Then the coater deposits a layer of plastic buffer coating for mechanical protection, which usually is 250um in diameter. And finally, the fiber is winded onto a spool for storage and transportation.]]>
So how is light guided and travels inside the fiber? This video shows a beam of light that travels inside a water stream by total internal reflection. Optical fibers work the same way. So let's take a look. A glass fiber has a cylindrical structure and is composed of three layers. At the center is the core, core has higher refractive index. Outside of core is the cladding layer. Cladding layer has lower refractive index than the core. The third layer is a plastic buffer coating. This buffer coating doesn't affect the fiber's optical performance, it is there for mechanical protection only. The right picture shows how light is coupled into the fiber's core and bounced back and forth in the core and travels along the fiber. The core and cladding layers are all based on fused silica which is a type of glass. But this fused silica is extremely clear, with almost no impurities. This transparency is extremely important, so that the light can travel for a very long distance, such as hundreds of kilometers with minimum loss. This makes trans-Pacific and trans-continent fiber optic communications possible. Here comes the question. Why doesn't the light leak out of the fiber? That is why we have to explain the phenomenon of total internal reflection. The left picture shows Snell's the law which guides how light travels at the interface of the core and cladding. The core has a higher refractive index n = 1.5. The cladding has a lower refractive index n = 1.4. When light incidents at the interface between the core and cladding at different angles, some power is reflected back, and some power enters into the cladding which is refracted. But when we increase the incident angle to greater than a critical angle theta c, no more light enters into the cladding, all light is reflected back into the core. This phenomenon is called Total Internal Reflection. Here total means 100% of the power is reflected back into the core. The manufacturing of glass fibers go through two steps. In the first step a preform is made. This preform has exactly the same proportion of core and cladding as final fiber product, but in a much bigger size. It looks like a thick glass rod, as shown in the bottom picture. Then the preform is hanged at the top of a fiber drawing tower. The tower is a couple of stories tall as shown in the right picture. The preform is heated by a furnace which softens the glass. The softened glass drips and pulled downward by gravity. A diameter monitor carefully monitors the fiber's diameter, which usually is 125um. Then the coater deposits a layer of plastic buffer coating for mechanical protection, which usually is 250um in diameter. And finally, the fiber is winded onto a spool for storage and transportation.]]> Thu, 25 Apr 2013 12:20:50 GMT /slideshow/what-is-fiber-optic/19971996 fiberoptics4sale@slideshare.net(fiberoptics4sale) What is fiber optic fiberoptics4sale So how is light guided and travels inside the fiber? This video shows a beam of light that travels inside a water stream by total internal reflection. Optical fibers work the same way. So let's take a look. A glass fiber has a cylindrical structure and is composed of three layers. At the center is the core, core has higher refractive index. Outside of core is the cladding layer. Cladding layer has lower refractive index than the core. The third layer is a plastic buffer coating. This buffer coating doesn't affect the fiber's optical performance, it is there for mechanical protection only. The right picture shows how light is coupled into the fiber's core and bounced back and forth in the core and travels along the fiber. The core and cladding layers are all based on fused silica which is a type of glass. But this fused silica is extremely clear, with almost no impurities. This transparency is extremely important, so that the light can travel for a very long distance, such as hundreds of kilometers with minimum loss. This makes trans-Pacific and trans-continent fiber optic communications possible. Here comes the question. Why doesn't the light leak out of the fiber? That is why we have to explain the phenomenon of total internal reflection. The left picture shows Snell's the law which guides how light travels at the interface of the core and cladding. The core has a higher refractive index n = 1.5. The cladding has a lower refractive index n = 1.4. When light incidents at the interface between the core and cladding at different angles, some power is reflected back, and some power enters into the cladding which is refracted. But when we increase the incident angle to greater than a critical angle theta c, no more light enters into the cladding, all light is reflected back into the core. This phenomenon is called Total Internal Reflection. Here total means 100% of the power is reflected back into the core. The manufacturing of glass fibers go through two steps. In the first step a preform is made. This preform has exactly the same proportion of core and cladding as final fiber product, but in a much bigger size. It looks like a thick glass rod, as shown in the bottom picture. Then the preform is hanged at the top of a fiber drawing tower. The tower is a couple of stories tall as shown in the right picture. The preform is heated by a furnace which softens the glass. The softened glass drips and pulled downward by gravity. A diameter monitor carefully monitors the fiber's diameter, which usually is 125um. Then the coater deposits a layer of plastic buffer coating for mechanical protection, which usually is 250um in diameter. And finally, the fiber is winded onto a spool for storage and transportation. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/whatisfiberoptic-130425122050-phpapp01-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> So how is light guided and travels inside the fiber? This video shows a beam of light that travels inside a water stream by total internal reflection. Optical fibers work the same way. So let&#39;s take a look. A glass fiber has a cylindrical structure and is composed of three layers. At the center is the core, core has higher refractive index. Outside of core is the cladding layer. Cladding layer has lower refractive index than the core. The third layer is a plastic buffer coating. This buffer coating doesn&#39;t affect the fiber&#39;s optical performance, it is there for mechanical protection only. The right picture shows how light is coupled into the fiber&#39;s core and bounced back and forth in the core and travels along the fiber. The core and cladding layers are all based on fused silica which is a type of glass. But this fused silica is extremely clear, with almost no impurities. This transparency is extremely important, so that the light can travel for a very long distance, such as hundreds of kilometers with minimum loss. This makes trans-Pacific and trans-continent fiber optic communications possible. Here comes the question. Why doesn&#39;t the light leak out of the fiber? That is why we have to explain the phenomenon of total internal reflection. The left picture shows Snell&#39;s the law which guides how light travels at the interface of the core and cladding. The core has a higher refractive index n = 1.5. The cladding has a lower refractive index n = 1.4. When light incidents at the interface between the core and cladding at different angles, some power is reflected back, and some power enters into the cladding which is refracted. But when we increase the incident angle to greater than a critical angle theta c, no more light enters into the cladding, all light is reflected back into the core. This phenomenon is called Total Internal Reflection. Here total means 100% of the power is reflected back into the core. The manufacturing of glass fibers go through two steps. In the first step a preform is made. This preform has exactly the same proportion of core and cladding as final fiber product, but in a much bigger size. It looks like a thick glass rod, as shown in the bottom picture. Then the preform is hanged at the top of a fiber drawing tower. The tower is a couple of stories tall as shown in the right picture. The preform is heated by a furnace which softens the glass. The softened glass drips and pulled downward by gravity. A diameter monitor carefully monitors the fiber&#39;s diameter, which usually is 125um. Then the coater deposits a layer of plastic buffer coating for mechanical protection, which usually is 250um in diameter. And finally, the fiber is winded onto a spool for storage and transportation.
What is fiber optic from FOSCO Fiber Optics
]]> 4323 8 https://cdn.slidesharecdn.com/ss_thumbnails/whatisfiberoptic-130425122050-phpapp01-thumbnail.jpg?width=120&height=120&fit=bounds presentation White http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 https://cdn.slidesharecdn.com/profile-photo-fiberoptics4sale-48x48.jpg?cb=1522957715 http://www.fiberoptics4sale.com https://cdn.slidesharecdn.com/ss_thumbnails/whatislcosbasedwavelengthselectiveswitch-130510135710-phpapp02-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/what-is-l-co-s-based-wavelength-selective-switch/20940416 What is l co s based w... https://cdn.slidesharecdn.com/ss_thumbnails/whatis16qammodulation-130425131517-phpapp01-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/what-is-16-qam-modulation/19974406 What is 16 qam modulation https://cdn.slidesharecdn.com/ss_thumbnails/whatisfiberoptic-130425122050-phpapp01-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/what-is-fiber-optic/19971996 What is fiber optic