FOA CFOT Terms and Definitions A thru
Z Exam Questions Correct Answers
Current Update (A Pass)
What is a linear measure of optical power? - Answers -Watts
What is the measure of the color of light, usually expressed in nanometeres (nm) or
microns (*m)? - Answers -Wavelength
What do you call a technique of sending signals of several different wavelengths of light
into the fiber simultaneously? - Answers -Wavelength Division Multiplexing (WDM)
The difference (in dB) between the power budget and the loss budget (i.e. the excess
power margin) is known as what? - Answers -Working Margin
A device that couples visible light into the fiber to allow visual tracing and testing of
continuity. - Answers -Visual Fault Locator (VFL)
A type of laser that emits light vertically out of the chip, not out of the edge, and is
widely used in fast multimode networks. - Answers -Vertical Cavity Surface Emitting
Laser (VCSEL)
A device which includes an LED or laser source and signal conditioning electronics that
is used to inject a signal into fiber. - Answers -Transmitter
Confinement of light into the core of a fiber by the reflection off the core-cladding
boundary. - Answers -Total internal reflection
A laser diode or LED used to inject an optical signal into fiber for testing loss of the fiber
or other components. - Answers -Test source
A kit of fiber optic instruments, incl. power meter, source and test accessories (to
measure loss and power) - Answers -Test kit
A short single fiber jumper cable with connectors on both ends. This cable must be
made of fiber and connectors of matching type... - Answers -Test cable
The preparation of the end of a fiber to allow connection to another fiber or active
device. - Answers -Termination
A communication device that allows conversation over unused fibers. - Answers -
Talkset
, LED that emits light perpendicular to the semiconductor chip. Most LEDs used in data
communications are this type. - Answers -Surface emitter LED
This is a multimode fiber where the core is all the same index of refraction. - Answers -
Step index fiber
Equilibrium modal distribution (EMD) in multimode fiber (achieved some distance from
the source) where the relative power in the modes becomes stable with increasing
distance. - Answers -Steady State Modal Distribution
The distribution of power among the output fibers of a coupler. - Answers -Splitting
Ratio
A device that provides for a permanent connection between two fibers. - Answers -
Splice (fusion or mechanical)
A laser diode or LED used to inject an optical signal into fiber - Answers -Source
A fiber with small core that allows only one mode of light to propagate. Commonly used
with laser sources for high speed, long distance links. - Answers -Singlemode Fiber
Term used for outer protective layers of a cable (jacket, armor and strength members) -
Answers -Sheath
The change of direction of light after striking small particals that causes loss in optical
fibers. - Answers -Scattering
A device that receives a fiber optic signal and regenerates it for retransmission (typical
in very long fiber optic links) - Answers -Repeater
Property of optical materials that relates to velocity of light in material. - Answers -
Refractive index
A device containing a photodiode and signal conditioning circuitry converting light to an
electrical signal in fiber optic links. - Answers -Receiver
Known good fiber optic jumper cable attached to power meter for loss testing. Must be
made of matching fiber and connectors of cables tested. - Answers -Receive cable
Large diameter glass rod where fiber is made or "drawn" from. - Answers -Preform
Dispersion in singlemode fiber caused by difference in speed of light of the fibers
polarization modes. - Answers -Polarization Mode Dispersion (PMD)
Fiber made with glass core and plastic cladding. - Answers -Plastic-clad Silica (PCS)
fiber
Z Exam Questions Correct Answers
Current Update (A Pass)
What is a linear measure of optical power? - Answers -Watts
What is the measure of the color of light, usually expressed in nanometeres (nm) or
microns (*m)? - Answers -Wavelength
What do you call a technique of sending signals of several different wavelengths of light
into the fiber simultaneously? - Answers -Wavelength Division Multiplexing (WDM)
The difference (in dB) between the power budget and the loss budget (i.e. the excess
power margin) is known as what? - Answers -Working Margin
A device that couples visible light into the fiber to allow visual tracing and testing of
continuity. - Answers -Visual Fault Locator (VFL)
A type of laser that emits light vertically out of the chip, not out of the edge, and is
widely used in fast multimode networks. - Answers -Vertical Cavity Surface Emitting
Laser (VCSEL)
A device which includes an LED or laser source and signal conditioning electronics that
is used to inject a signal into fiber. - Answers -Transmitter
Confinement of light into the core of a fiber by the reflection off the core-cladding
boundary. - Answers -Total internal reflection
A laser diode or LED used to inject an optical signal into fiber for testing loss of the fiber
or other components. - Answers -Test source
A kit of fiber optic instruments, incl. power meter, source and test accessories (to
measure loss and power) - Answers -Test kit
A short single fiber jumper cable with connectors on both ends. This cable must be
made of fiber and connectors of matching type... - Answers -Test cable
The preparation of the end of a fiber to allow connection to another fiber or active
device. - Answers -Termination
A communication device that allows conversation over unused fibers. - Answers -
Talkset
, LED that emits light perpendicular to the semiconductor chip. Most LEDs used in data
communications are this type. - Answers -Surface emitter LED
This is a multimode fiber where the core is all the same index of refraction. - Answers -
Step index fiber
Equilibrium modal distribution (EMD) in multimode fiber (achieved some distance from
the source) where the relative power in the modes becomes stable with increasing
distance. - Answers -Steady State Modal Distribution
The distribution of power among the output fibers of a coupler. - Answers -Splitting
Ratio
A device that provides for a permanent connection between two fibers. - Answers -
Splice (fusion or mechanical)
A laser diode or LED used to inject an optical signal into fiber - Answers -Source
A fiber with small core that allows only one mode of light to propagate. Commonly used
with laser sources for high speed, long distance links. - Answers -Singlemode Fiber
Term used for outer protective layers of a cable (jacket, armor and strength members) -
Answers -Sheath
The change of direction of light after striking small particals that causes loss in optical
fibers. - Answers -Scattering
A device that receives a fiber optic signal and regenerates it for retransmission (typical
in very long fiber optic links) - Answers -Repeater
Property of optical materials that relates to velocity of light in material. - Answers -
Refractive index
A device containing a photodiode and signal conditioning circuitry converting light to an
electrical signal in fiber optic links. - Answers -Receiver
Known good fiber optic jumper cable attached to power meter for loss testing. Must be
made of matching fiber and connectors of cables tested. - Answers -Receive cable
Large diameter glass rod where fiber is made or "drawn" from. - Answers -Preform
Dispersion in singlemode fiber caused by difference in speed of light of the fibers
polarization modes. - Answers -Polarization Mode Dispersion (PMD)
Fiber made with glass core and plastic cladding. - Answers -Plastic-clad Silica (PCS)
fiber
