Print this page Optical Fibers, Lasers and Modulators
Roy Timpe, P.E.
Course Outline
Fiber optic communication systems have enabled the affordability and ubiquity of the Internet, as well as their earlier application in telephony. These systems are found within buildings, corporate campuses, undersea cables, and long haul trunk lines between cities. This four hour online course discusses the physical devices and components used in these systems. This course will enable the student to understand these systems at the physical layer. The student will also be able to identify and avoid some safety issues with the installation and use of these devices.
This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.
Learning Objective
At the conclusion of this course, the student will:
- Understand how the light is guided in an optical fiber;
- Be able to recognize the difference between single mode and multi mode fibers;
- Understand why certain wavelengths of light have been chosen for fiber systems;
- Understand the principles of semiconductor laser diodes;
- Be able to explain the principles of detector diodes used in optical receivers;
- Understand the principles of the three most common ways to modulate light in a digital fiber system; and
- Be able to recognize and avoid the optical safety hazards of these fiber systems.
Intended Audience
This course is intended for engineers and contractors.
Benefit for Attendee
Attendee of this course will understand how these fiber systems work at the most basic level. The attendee will understand the safety issues associated with these systems.
Course Introduction
Virtually all optical devices used in fiber optics are based on the diode. The diode functions as a check valve for electricity. Forward biased the the properly structured diode can provide optical gain for photons, making the laser possible. Reverse biased it can detect photons.
Dispersion limits the length of an optical fiber link. There are two types of dispersion: modal and wavelength. Wavelength dispersion is exacerbated by multiple laser modes and laser chirp. Methods of modulating the laser external to the cavity have become necessary to reduce chirp. These methods are discussed, along with laser safety as it relates to fiber systems.
Course Content
The course content is contained in the following PDF file:
Optical Fibers, Lasers and Modulators
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Course Summary
Optical transmitters, optical receivers, and the fiber itself comprise the physical layer of these modern communication systems. The materials have dictated the several different wavelengths used. The bit rate and length of transmission dictate the type of fiber used, the power level, and the method of modulation. All of these choices not only affect the performance of the system, but also dictate safety concerns for the engineers and technicians that install and maintain these systems.
Quiz
Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.
DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.
