iSnare.com - Free Content Articles Directory
Authors Contents [Advanced Search][Add OpenSearch][Job Search]
Distribute your articles to thousands of article sites for only $2 and below! Read more...

Index  Computers and Technology
 

How Are Optical Fibers Made?

 
[ Contact the Author] [ Send to a Friend] [ Article Publisher] [Make PDF] [ Print] [ Bookmark & Share]
 
Read our Terms of Service before reprinting this article. The submitter specified above has claimed the rights to this article.
Colin Yao

1. Materials for optical fibers

There are two major types of optical fibers: plastic optical fibers (POF) and glass optical fibers

Plastic optical fibers are usually made for lighting or decoration such as fiber optic christmas trees. They are also used on short range communication applications such as on vehicles and ships. Because of plastic optical fiber's high attenuation, they have very limited information carrying bandwidth.

When we talk about fiber optic networks and fiber optic telecommunications, we actually mean glass optical fibers. Glass optical fibers are mostly made from fused silica (90% at least). Other glass materials such as fluorozirconate and fluoroaluminate are also used in some specialty fibers.

2. Glass optical fiber manufacturing process

Before we start talking how to manufacture glass optical fibers, let's first take a look at its cross section structure.

Optical fiber cross section is a circular structure composed of three layers inside out.

A. The inner layer is called the core. This layer guides the light and prevent light from escaping out by a phenomenon called total internal reflection. The core's diameter is 9um for single mode fibers and 50um or 62.5um for multimode fibers.

B. The middle layer is called the cladding. It has 1% lower refractive index than the core material. This difference plays a vital part in total internal reflection phenomenon. The cladding's diameter is usually 125um.

C. The outer layer is called the coating. It is actually epoxy cured by ultraviolet light. This layer provides mechanical protection for the fiber and makes the fiber flexible for handling. Without this coating layer, the fiber will be very fragile and easy to break.

Because of optical fiber's extreme tiny size, it is not practical to produce it in a single step. Three steps are required as we explain below.

1). Preparing the fiber preform

Standard optical fibers are made by first constructing a large-diameter preform, with a carefully controlled refractive index profile. Only several countries including US have the ability to make large volume, high quality fiber preforms.

The process to make glass preform is called MOCVD (modified chemical vapor deposition).

In MCVD, a 40cm long hollow quartz tube is fixed horizontally and rotated slowly on a special lathe. Oxygen is bubbled through solutions of silicon chloride (SiCl4), germanium chloride (GeCl4) and/or other chemicals. This precisely mixed gas is then injected into the hollow tube.

As the lathe turns, a hydrogen burner torch is moved up and down the outside of the tube. The gases are heated up by the torch up to 1900 kelvins. This extreme heat causes two chemical reactions to happen.

A. The silicon and germanium react with oxygen, forming silicon dioxide (SiO2) and germanium dioxide (GeO2).
B. The silicon dioxide and germanium dioxide deposit on the inside of the tube and fuse together to form glass.

The hydrogen burner is then traversed up and down the length of the tube to deposit the material evenly. After the torch has reached the end of the tube, it is then brought back to the beginning of the tube and the deposited particles are then melted to form a solid layer. This process is repeated until a sufficient amount of material has been deposited.

2). Drawing fibers on a drawing tower

The preform is then mounted to the top of a vertical fiber drawing tower.

The preforms is first lowered into a 2000 degrees Celsius furnace. Its tip gets melted until a molten glob falls down by gravity. The glob cools and forms a thread as it drops down.

This starting strand is then pulled through a series of buffer coating cups and UV light curing ovens, finally onto a motor controlled cylindrical fiber spool.

The motor slowly draws the fiber from the heated preform. The formed fiber diameter is precisely controlled by a laser micrometer. The running speed of the fiber drawing motor is about 15 meters/second. Up to 20km of continuous fibers can be wound onto a single spool.

3). Testing finished optical fibers

Telecommunication applications require very high quality glass optical fibers. The fiber's mechanical and optical properties are then checked.

Mechanical Properties:

A. Tensile strength: Fiber must withstand 100,000 (lb/square inch) tension
B. Fiber geometry: Checks fiber's core, cladding and coating sizes

Optical Properties:

A. Refractive index profile: The most critical optical spec for fiber's information carrying bandwidth
B. Attenuation: Very critical for long distance fiber optic links
C. Chromatic dispersion: Becomes more and more critical in high speed fiber optic telecommunication applications

Important NoticeDISCLAIMER: All information, content, and data in this article are sole opinions and/or findings of the individual user or organization that registered and submitted this article at Isnare.com without any fee. The article is strictly for educational or entertainment purposes only and should not be used in any way, implemented or applied without consultation from a professional. We at Isnare.com do not, in anyway, contribute or include our own findings, facts and opinions in any articles presented in this site. Publishing this article does not constitute Isnare.com's support or sponsorship for this article. Isnare.com is an article publishing service. Please read our Terms of Service for more information.

Want to know even more? Check out these lc sc fiber patch, sc lc patch, sc to lc patch cable on Fiber Optics For Sale Co web site.

Article Tags: fiber [See Dictionary], fibers [See Dictionary], optical [See Dictionary]
Got a question about this article? Ask the community!
Article published on March 12, 2008 at Isnare.com
 
Rate this article:

How Do Fiber Optic Cleavers Precisely Cut Optical Fibers in a Flash?
Submitted by: Colin Yao

:: What is optical fiber cleaving Simply put, optical fiber cleaving is the art of cutting glass optical fibers at a perfect 90° angle with a mirror like surface...

Dummies' Guide to Fiber Optic Bit Error Ratio (BER) Measurement
Submitted by: Colin Yao

Bit error ratio (BER) measurement is the fundamental measurement of the quality of the fiber optic communication system...

The Secrets of Choosing Ribbon Fiber
Submitted by: Colin Yao

Do you know why it is so expensive to install Fiber To The Home Why Bell companies are reluctant to deploy fiber optic network directly to consumers in a large scale...

Everything You Need to Know About Fiber Optic Ethernet
Submitted by: Colin Yao

In the last decade, a wide variety of applications have been developed that covers a dozen of datacom networking technologies...

How to Design a High Performance Optical Receiver?
Submitted by: Colin Yao

The structure of an optical receiver is simple: consisting of just a photodiode to produce the electrical current and an amplifier...

How to Design a Highly Reliable Fiber Optic Network
Submitted by: Colin Yao

What happens if a major fiber optic cable is cut or a major hubbing location is destroyed in a fiber network...

Dummies' Guide to Fiber Optic Sensors
Submitted by: Colin Yao

What are fiber optic sensors The fundamental characteristic of all fiber optic sensors is that they depend on some optical properties, such as intensity, phase, state of polarization and wavelength, to be modulated by measurands...

Understanding The Basics Of All Optical Switching
Submitted by: Colin Yao

What is all-optical switching All-optical switching is a process by which light, usually in the form of digital communication signals, is routed from one transmission channel to another, or modulated, without intermediate conversion to another format...

What Are Fiber Optic Circulators? Fiber Optic Communication Tutorial Series
Submitted by: Colin Yao

What is an optical circulator The optical circulator has similar function and design as the optical isolator...

What Are Fiber Optic Isolators? Fiber Optic Communication Tutorial Series
Submitted by: Colin Yao

Why do we need fiber optic isolator Light can be reflected back and forth...

What Are Fiber Optic Attenuators? Fiber Optic Communication Tutorial Series
Submitted by: Colin Yao

Why Do We Need Fiber Optic Attenuators A fiber optic attenuator, also called an optical attenuator, simulates the loss the would be caused by a long length of fiber...

The Current Status of FTTH in the US and the Rest of the World
Submitted by: Colin Yao

Understanding FTTH (Fiber To The Home) FTTH is an all-fiber connection to the home which provides a minimum of 155Mbps bandwidth on both up stream and down stream directions...

What is WDM (Wavelength Division Multiplexing) For Fiber Optic Communication? Fiber Optic Tutorial Series
Submitted by: Colin Yao

What is WDM WDM is the abbreviation for Wavelength Division Multiplexing...

Some Basic Concepts of Fiber Optic Loss Testing
Submitted by: Colin Yao

When testing loss in a fiber optic link, some basic principles must be kept in mind all the time 1...

The Future of Fiber Optic Communication
Submitted by: Colin Yao

There is no question that fiber optic communication is our future Fiber optic communication industry has been enjoying amazing growth for over 15 years...

School Surveillance Applications
Submitted by: Wesley Fernley

In this day in age it has almost become necessity that our schools, from the elementary level through the college level, include video surveillance for precautionary measures to help provide a secure environment for staff and especially for the students attending...

Using IP Surveillance Cameras in Check Cashing Locations
Submitted by: Wesley Fernley

As tax season approaches and during this challenging economy, payday loan check cashing locations are busier than ever...

How to Install Aftermarket Stereo in Vauxhall Agila
Submitted by: Jack Wylde

DESCRIPTION: The radio installation in VAUXHALL AGILA Some Cars have steering controls from new and when you replace your radio...

Don't Ruin Your Laminator - 4 Reasons to Always Use a Carrier With Your Pouch Laminating Machine
Submitted by: Jeff McRitchie

One of the most important supplies you'll need when getting ready to use a pouch laminator is a carrier...

GBC ShredMaster CC195 Cross-Cut Shredder Review
Submitted by: Jeff McRitchie

If you've visited an office supply store recently or checked out paper shredders on the Internet, it probably seems like paper shredders are all alike, especially in the looks department...

Frequently Asked Questions About Spiral Coil Binding
Submitted by: Jeff McRitchie

Coil binding - also known as spiral binding - is a very popular method of binding, but it can be difficult to understand how it's done...

An Overview of the GBC C-75 Comb Binding Machine
Submitted by: Jeff McRitchie

If you are looking for an inexpensive comb binding machine for your office or home office you might be considering the GBC C75...

5 Great Features of the Rhin-O-Tuff HD6500
Submitted by: Jeff McRitchie

Designed for the heaviest duty users such as print and copy shops, binderies and large organizations, the Rhino Tuff HD6500 is a machine that offers top of the line flexibility and capacity...

Comparing the Swingline SmartCut EasyBlade and EasyBlade Plus Rotary Trimmers
Submitted by: Jeff McRitchie

At first glance, Swingline's SmartCut EasyBlade and EasyBlade Plus may look very similar, except for the price...

Five Reasons to Consider the Rhino-Tuff OD4000 Modular Binding Punch
Submitted by: Jeff McRitchie

Though it may be the smallest of Rhino's electric interchangeable punches, the OD4000 offers you about as much as a binding punch can offer...

Carnival of New Digital Camera Camcorder
Submitted by: Leo Vegner

The category of camcorder is one broad category of the old and new, dynamic and basic offing in the world of digital photography...

DirectAccess Takes the Place of VPN For Windows Seven
Submitted by: Gregg Housh

Microsoft has unveiled Direct Access for Windows 7 and Windows Server 2008, remotely connecting users to their office as if they were right there...

Looking For Reliable Software To Restore Memory Cards Files
Submitted by: Lance Edwards

Well, bad things always happen There is no exception...

Where Can You Sell Your Used Toner Cartridges?
Submitted by: Adriana N

Many hi-tech devices now come with many accessories, components, and specific parts For instance, there are many computer related devices that over time will require new parts...

History of Dell Computers
Submitted by: Adriana Noton

Dell is a well-known computer company that has been around for over 20 years Most people recognize the name and thousands of people buy new Dell products every day...

Isnare.com Footer Divider

© 2004-2009. Isnare Free Articles - An Isnare Online Technologies Free Articles Project. All Rights Reserved.   Privacy Policy