Optical Fiber Waveguides - Revision history

Cmditradmin at 19:55, 29 December 2009

2009-12-29T19:55:44Z

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	[[category:Photonics ~~Applications~~]]		[[category:Photonics applications]]
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Cmditradmin at 19:17, 29 December 2009

2009-12-29T19:17:42Z

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			[[category:Photonics Applications]]
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Nsylvain at 00:38, 27 August 2009

2009-08-27T00:38:01Z

← Older revision		Revision as of 17:38, 26 August 2009
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	There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.		There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.

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Cmditradmin at 23:04, 25 August 2009

2009-08-25T23:04:22Z

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	The fiber can support only one mode when V < 2.405		The fiber can support only one mode when V < 2.405

	For n<sub>1</sub> = 1.48 and n<sub>2</sub> = 1.46, the radius of the core a <2.~~7mu~~ m		For n<sub>1</sub> = 1.48 and n<sub>2</sub> = 1.46, the radius of the core a <2.7μm

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	[[Image:GI_fiber.png\|thumb\|300px\|Graded index fiber]]		[[Image:GI_fiber.png\|thumb\|300px\|Graded index fiber]]

Cmditradmin at 23:03, 25 August 2009

2009-08-25T23:03:55Z

← Older revision		Revision as of 16:03, 25 August 2009
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	[[Image:SI_fiber.png\|thumb\|300px\|Step index fiber]]		[[Image:SI_fiber.png\|thumb\|300px\|Step index fiber]]
	These are referred to as step index fibers. The y axis refers to the index of refraction. The x axis is the distance from the center of the core. So the highest index of refraction (n1) is found in the core and there is a significant step in the index of refraction (n2) at the interface with the cladding.		These are referred to as step index fibers. The y axis refers to the index of refraction. The x axis is the distance from the center of the core. So the highest index of refraction (n<sub>1</sub>) is found in the core and there is a significant step in the index of refraction (n<sub>2</sub>) at the interface with the cladding.


	In most practical waveguides the refractive indices of the core and cladding differ from each other by only a few percent.		In most practical waveguides the refractive indices of the core and cladding differ from each other by only a few percent.

			The number of modes in a step-index circular waveguide is determined by the V parameter where

	:<math>\frac {d} {\lambda_0} ~~< \frac {1} {2~~(n^~~{2}_{1} –~~ n^~~{2}_{2}~~)^{1/2}}\,\!</math>		:<math>V= \frac {2\pi a} {\lambda_0} (n^2_1 - n^2_2)^{1/2}\,\!</math>

			where
			:<math>a\,\!</math> is the core radius

	:<math>n^~~{2}_{2}~~)^{1/2}\,\!</math> is referred to as the numerical aperature, the larger this term the larger the number of modes.		:<math>(n^2_1 - n^2_2)^{1/2}\,\!</math> is referred to as the numerical aperature, the larger this term the larger the number of modes.

	The fiber can support only one mode when V < 2.405		The fiber can support only one mode when V < 2.405

	For n1 = 1.48 and n2 = 1.46, the radius of the core a <2.7mu m		For n<sub>1</sub> = 1.48 and n<sub>2</sub> = 1.46, the radius of the core a <2.7mu m
			<br clear='all'>
	[[Image:GI_fiber.png\|thumb\|300px\|Graded index fiber]]		[[Image:GI_fiber.png\|thumb\|300px\|Graded index fiber]]

	There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.		There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.

	<table id="toc" style="width: 100%">		<table id="toc" style="width: 100%">
	<tr>		<tr>

Cmditradmin at 22:57, 25 August 2009

2009-08-25T22:57:21Z

← Older revision		Revision as of 15:57, 25 August 2009
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	[[Image:Circular_dielect_wg.png\|thumb\|300px\|]]		[[Image:Circular_dielect_wg.png\|thumb\|300px\|Circular dielectric waveguide]]
	A circular dielectric waveguide or fiber optic has an internal core that has a higher index of refraction than the cladding. At a certain diameter there is an angle that is less than the critical angle so there is total internal reflection.		A circular dielectric waveguide or fiber optic has an internal core that has a higher index of refraction than the cladding. At a certain diameter there is an angle that is less than the critical angle so there is total internal reflection.


	[[Image:SI_fiber.png\|thumb\|300px\|]]		[[Image:SI_fiber.png\|thumb\|300px\|Step index fiber]]
	These are referred to as step index fibers. The y axis refers to the index of refraction. The x axis is the distance from the center of the core. So the highest index of refraction (n1) is found in the core and there is a significant step in the index of refraction (n2) at the interface with the cladding.		These are referred to as step index fibers. The y axis refers to the index of refraction. The x axis is the distance from the center of the core. So the highest index of refraction (n1) is found in the core and there is a significant step in the index of refraction (n2) at the interface with the cladding.

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	For n1 = 1.48 and n2 = 1.46, the radius of the core a <2.7mu m		For n1 = 1.48 and n2 = 1.46, the radius of the core a <2.7mu m

	[[Image:GI_fiber.png\|thumb\|300px\|]]		[[Image:GI_fiber.png\|thumb\|300px\|Graded index fiber]]

	There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.		There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.

Cmditradmin at 21:17, 20 August 2009

2009-08-20T21:17:07Z

@@ Line 18: / Line 18: @@
 :<math>\frac {d} {\lambda_0} < \frac {1} {2(n^{2}_{1} – n^{2}_{2})^{1/2}}\,\!</math>
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 :<math>n^{2}_{2})^{1/2}\,\!</math> is referred to as the numerical aperature, the larger this term the larger the number of modes.
@@ Line 35: / Line 29: @@
 There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.

Cmditradmin at 21:16, 20 August 2009

2009-08-20T21:16:53Z

← Older revision		Revision as of 14:16, 20 August 2009
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	:<math>\frac {d} {\lambda_0} < \frac {1} {2(n^{2}_{1} – n^{2}_{2})^{1/2}}\,\!</math>		:<math>\frac {d} {\lambda_0} < \frac {1} {2(n^{2}_{1} – n^{2}_{2})^{1/2}}\,\!</math>
			<table id="toc" style="width: 100%">
			<tr>
			<td style="text-align: left; width: 33%">[[Planar Dielectric Waveguides\|Previous Topic]]</td>
			<td style="text-align: center; width: 33%">[[Main_Page#Optical Fibers, Waveguides, and Lasers\|Return to Optical Fibers, Waveguides, and Lasers Menu]]</td>
			<td style="text-align: right; width: 33%">[[Dispersion and Attenuation Phenomena\|Next Topic]]</td>
			</tr>
			</table>

	:<math>n^{2}_{2})^{1/2}\,\!</math> is referred to as the numerical aperature, the larger this term the larger the number of modes.		:<math>n^{2}_{2})^{1/2}\,\!</math> is referred to as the numerical aperature, the larger this term the larger the number of modes.

Cmditradmin at 23:50, 10 August 2009

2009-08-10T23:50:51Z

← Older revision		Revision as of 16:50, 10 August 2009
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			[[Image:Circular_dielect_wg.png\|thumb\|300px\|]]
			A circular dielectric waveguide or fiber optic has an internal core that has a higher index of refraction than the cladding. At a certain diameter there is an angle that is less than the critical angle so there is total internal reflection.

	A circular dielectric waveguide or fiber optic has an internal core that has a higher index of refraction than the cladding. At a certain diameter there is an angle that is less than the critical angle so there is total internal reflection.

			[[Image:SI_fiber.png\|thumb\|300px\|]]
	These are referred to as step index fibers. The y axis refers to the index of refraction. The x axis is the distance from the center of the core. So the highest index of refraction (n1) is found in the core and there is a significant step in the index of refraction (n2) at the interface with the cladding.		These are referred to as step index fibers. The y axis refers to the index of refraction. The x axis is the distance from the center of the core. So the highest index of refraction (n1) is found in the core and there is a significant step in the index of refraction (n2) at the interface with the cladding.

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	n^{2}_{2})^{1/2} is referred to as the numerical aperature, the larger this term the larger the number of modes.		:<math>n^{2}_{2})^{1/2}\,\!</math> is referred to as the numerical aperature, the larger this term the larger the number of modes.

	The fiber can support only one mode when V < 2.405		The fiber can support only one mode when V < 2.405

	For n1 = 1.48 and n2 = 1.46, the radius of the core a <2.7mu m		For n1 = 1.48 and n2 = 1.46, the radius of the core a <2.7mu m

	[[Image:GI_fiber.png\|thumb\|300px\|]]		[[Image:GI_fiber.png\|thumb\|300px\|]]

	There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.		There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.

Cmditradmin at 23:46, 10 August 2009

2009-08-10T23:46:58Z

← Older revision		Revision as of 16:46, 10 August 2009
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	</tr>		</tr>
	</table>		</table>

			A circular dielectric waveguide or fiber optic has an internal core that has a higher index of refraction than the cladding. At a certain diameter there is an angle that is less than the critical angle so there is total internal reflection.

			These are referred to as step index fibers. The y axis refers to the index of refraction. The x axis is the distance from the center of the core. So the highest index of refraction (n1) is found in the core and there is a significant step in the index of refraction (n2) at the interface with the cladding.


			In most practical waveguides the refractive indices of the core and cladding differ from each other by only a few percent.


			:<math>\frac {d} {\lambda_0} < \frac {1} {2(n^{2}_{1} – n^{2}_{2})^{1/2}}\,\!</math>


			n^{2}_{2})^{1/2} is referred to as the numerical aperature, the larger this term the larger the number of modes.

			The fiber can support only one mode when V < 2.405

			For n1 = 1.48 and n2 = 1.46, the radius of the core a <2.7mu m
			[[Image:GI_fiber.png\|thumb\|300px\|]]

			There is current research to develop a core with a graded index of refraction that gradually decreases to equal that of the cladding. This is referred to as a graded index fiber.