Description : Light rays that are emitted simultaneously from an LED and propagated down an optical fiber do not arrive at the far end of the fiber at the same time results to ∙ A. intramodal dispersion ∙ B. pulse length dispersion ∙ C. modal dispersion ∙ D. wavelength dispersion
Last Answer : D. wavelength dispersion
Description : Optical amplifiers use ____________________-doped glass.
Last Answer : erbium
Description : Optical fibers for telecommunications are typically about _____ mils thick and consists of a glass core, a glass cladding of lower index of refraction, and a protective coating ∙ a. 5 ∙ b. 6 ∙ c. 7 ∙ d. 8
Last Answer : ∙ a. 5
Description : An increase in light intensity produces fast optic switching due to ∙ a. Increase in index of glass ∙ b. Amplification of optical signal ∙ c. High gain ∙ d. Photoconductivity
Last Answer : b. Amplification of optical signal
Description : Which is not a possible cause of optical fiber loss? ∙ a. Impurities ∙ b. Glass attenuation ∙ c. Stepped index operation ∙ d. Microbending
Last Answer : ∙ c. Stepped index operation
Description : The ultrapure glass used to manufacture optical fibers is approximately ___pure ∙ a. 99.9 % ∙ b. 99.99 % ∙ c. 99.999 % ∙ d. 99.9999 %
Last Answer : d. 99.9999 %
Description : SONET stands for ____________________ Optical Network.
Last Answer : Synchronous
Description : SONET stands for ∙ a. System Optical Network ∙ b. Synchronous Optical Network ∙ c. Silica Optic Network ∙ d. System Optical Fiber Net
Last Answer : ∙ b. Synchronous Optical Network
Description : SONET stands for: a. Simple Optical Network b. Standard Optical Network c. Synchronous Optical Network d. none of the above
Last Answer : c. Synchronous Optical Network
Description : The upper pulse rate and information-carrying capacity of a cable is limited by ∙ A. pulse shortening ∙ B. attenuation ∙ C. light leakage ∙ D. modal dispersion
Last Answer : D. modal dispersion
Description : It indicates what signal frequencies can be propagated through a given distance of fiber cable. ∙ A. Bandwidth Distance Product ∙ B. Pulse width dispersion ∙ C. Rise time ∙ D. Cutoff frequency
Last Answer : A. Bandwidth Distance Product
Description : The upper pulse rate and information carrying capacity of a cable is limited by ∙ a. Pulse shortening ∙ b. Attenuation ∙ c. Light leakage ∙ d. Modal dispersion
Last Answer : ∙ d. Modal dispersion
Description : Which is the proper measurement of average power emitted by a pulsed laser? ∙ a. Energy x time ∙ b. Pulse energy x repetition rate ∙ c. Pulse energy / repetition rate ∙ d. Peak power x pulse length
Last Answer : ∙ b. Pulse energy x repetition rate
Description : A type of index of an optical fiber that has no cladding and whose central core has a non-uniform refractive index. ∙ A. graded index ∙ B. multimode ∙ C. single mode ∙ D. step-index
Last Answer : ∙ A. graded index
Description : A type of index profile of an optical fiber that has a central core and outside cladding with a uniform refractive index ∙ A. multimode ∙ B. graded index ∙ C. step-index ∙ D. single mode
Last Answer : ∙ C. step-index
Description : In SONET, OC-1 stands for: a. Optical Carrier level one b. Optical Coupler unidirectional c. Optical Channel one d. Optical Cable type 1
Last Answer : a. Optical Carrier level one
Description : Optical amplifiers use a ____________________ laser.
Last Answer : pump
Description : For safety, you should never ____________________ at the end of an optical fiber unless you know it is not connected to a light source.
Last Answer : look
Description : The optical fiber is not free to move around in a ____________________ cable.
Last Answer : tight-buffer
Last Answer : loose-tube
Description : With optical fiber, ____________________ light is more common than visible light.
Last Answer : infrared
Description : Optical fiber relies on total ____________________ reflection.
Last Answer : internal
Description : Which of the following is not a part of the optical spectrum? ∙ A. infrared ∙ B. ultraviolet ∙ C. visible color ∙ D. x-rays
Last Answer : ∙ D. x-rays
Description : The minimum optical power a light detector can receive and still produce a usable electrical output signal. ∙ A. light responsivity ∙ B. light sensitivity ∙ C. light collectivity ∙ D. illumination
Last Answer : B. light sensitivity
Description : The term responsivity as it applies to a light detector is best described as ∙ A. the time required for the signal to go from 10 to 90 percent of maximum amplitude ∙ B. the ratio of the diode ... . the ratio of the input power to output power ∙ D. the ratio of output current to input current
Last Answer : the ratio of the diode output current to the input optical power
Description : For a 300-m optical fiber cable with a bandwidth distance product of 600 MHz-km, determine the bandwidth. ∙ A. 5 GHz ∙ B. 1 GHz ∙ C. 2 GHz
Last Answer : C. 2 GHz
Description : For a single mode optical cable with 0.25 dB/km loss, determine the optical power 100 km from a 0.1-mW light source. ∙ A. -45 dBm ∙ B. -15 dBm ∙ C. -35 dBm
Last Answer : ∙ C. -35 dBm
Description : The three major groups of the optical system are ∙ A. the components, the data rate and the response time ∙ B. the source, the link and the receiver ∙ C. the transmitter, the cable and the receiver ∙ D. the source, the link and the detector
Last Answer : B. the source, the link and the receiver
Description : Optical power is sometimes called __________. ∙ A. Radiant emission ∙ B. Radiant power ∙ C. Radiant flux ∙ D. Radiant optics
Last Answer : C. Radiant flux
Description : It is described as the flow of light energy past a given point in a specified time ∙ A. Optical radiation ∙ B. Optical impedance ∙ C. Optical illusion ∙ D. Optical power
Last Answer : D. Optical power
Description : In radiometric terms, it measures the rate at which electromagnetic waves transfer light energy ∙ A. Optical radiation ∙ B. Optical impedance ∙ C. Optical illusion ∙ D. Optical power
Description : Developed an optical fiber with losses less that 2 dB/km ∙ A. Kao and Bockham ∙ B. Maiman, Kao and Bockham ∙ C. Maiman and Schawlow ∙ D. Kapron, Keck and Maurer
Last Answer : ∙ A. Kao and Bockham
Description : The scientist who built the first optical maser ∙ A. Charles Townes ∙ B. GA Bockham ∙ C. Theodore Maiman ∙ D. ACS Van Heel
Last Answer : ∙ C. Theodore Maiman
Description : Approximately what is the frequency limit of the optical fiber? ∙ A. 20 MHz ∙ B. 1 MHz ∙ C. 100 MHz ∙ D. 40 GHz
Last Answer : ∙ D. 40 GHz
Description : Which modulation methods are the most widely used in optical systems? ∙ a. Phase and frequency modulations ∙ b. Polarization modulation and phase modulation ∙ c. Intensity modulation and phase modulation ∙ d. Intensity modulation and polarization modulation
Last Answer : Intensity modulation and polarization modulation
Description : Used to test a fiber optics splice ∙ a. Spectrum analyzer ∙ b. Oscilloscope ∙ c. Optical power meter ∙ d. Field strength meter
Last Answer : c. Optical power meter
Description : What is the frequency limit of an optical fiber? ∙ a. 20 GHz ∙ b. 30 GHz ∙ c. 40 GHz ∙ d. 50 GHz
Last Answer : ∙ c. 40 GHz
Description : Which optical detector is used when high sensitivity and bandwidth are required? ∙ a. PMT ∙ b. APD ∙ c. PIN ∙ d. Phototransistor
Last Answer : a. PMT
Description : The _____ is equal to the number of electrons emitted per second times the electron charge ∙ a. Intensity ∙ b. Optical power ∙ c. Photocurrent ∙ d. Responsitivity
Last Answer : c. Photocurrent
Description : Optical detectors are square-law devices because they respond to _____ rather than amplitude ∙ a. Intensity ∙ b. Light ∙ c. Density ∙ d. Photon
Last Answer : a. Intensity
Description : One of the following is not a solid-state optical detector ∙ a. APD ∙ b. PIN ∙ c. PMT ∙ d. Phototransistors
Last Answer : . PMT
Description : In solid-state optical detectors, the excited charge is transported in the solid by ∙ a. Holes and protons ∙ b. Holes and electrons ∙ c. Anion and cation ∙ d. Protons and photons
Last Answer : ∙ b. Holes and electrons
Description : Light traveling in optical fiber follows which of the following principles. ∙ a. Huygen’s principle ∙ b. Reflection theory ∙ c. Light theory ∙ d. Snell’s law
Last Answer : d. Snell’s law
Description : Optical cable testers are used for ∙ a. Checking refractive index ∙ b. Light power out of a fiber ∙ c. Non-calibrated light into a fiber
Last Answer : b. Light power out of a fiber
Last Answer : ∙ b. Light power out of a fiber
Description : An IC that represents a short distance one-way optical communications ∙ a. Optoisolator ∙ b. Insulator ∙ c. Multivibrator ∙ d. Optical IC
Last Answer : a. Optoisolator
Description : The graded-index multimode optical fiber has a core diameter of _____ nm. ∙ a. 0.5 ∙ b. 0.05 ∙ c. 0.0005 ∙ d. 5
Last Answer : ∙ a. 0.5
Description : A step-index multimode optical fiber has a core diameter of _____ nm. ∙ a. 0.02 ∙ b. 0.2 ∙ c. 2 ∙ d. 0.002
Last Answer : b. 0.2
Description : A single mode optical fiber has a core diameter of _____ nm. ∙ a. 0.1 ∙ b. 0.01 ∙ c. 0.2 ∙ d. 0.05
Last Answer : a. 0.1
Description : OTDR stands for ∙ a. Optical Time Domain Reflectometer ∙ b. Optical Transmit Direction Return ∙ c. Optical Time Domain Time Regeneration ∙ d. Overtime Direct Reference
Last Answer : c. Optical Time Domain Time Regeneration