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
Last Answer : D. Optical power
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 : The leakage current that flows through a photodiode with no light input ∙ A. dark voltage ∙ B. dark impedance ∙ C. dark power ∙ D. dark current
Last Answer : D. dark current
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 : 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 : 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 : EMD is best described by which statement? ∙ A. 70 percent of the core diameter and 70% of the fiber NA should be filled with light. ∙ B. 70 percent of the fiber diameter and 70% of the ... be measured at the output. ∙ D. 70 percent of the unwanted wavelengths should be attenuated by the fiber.
Last Answer : 70 percent of the core diameter and 70% of the fiber NA should be filled with light.
Description : Light intensity is generally described in terms of __________ and measured in _________. ∙ A. Luminous flux density; Lumens per unit area ∙ B. Luminous flux intensity; Lumens per unit area ∙ C. Luminous flux density; Lumens per unit volume ∙ D. Luminous flux intensity; Lumens per unit volume
Last Answer : Luminous flux density; Lumens per unit area
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 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 : 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 : 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 of the following contributes to the broadening of laser emission bandwidth? ∙ a. Doppler shift of moving atoms and molecules ∙ b. Amplification within the laser medium ∙ c. Coherence of the laser light ∙ d. Optical pumping of the laser transition
Last Answer : Doppler shift of moving atoms and molecules
Description : . Is a non-coherent light source foe optical communications system. ∙ a. ILD ∙ b. LED ∙ c. APD ∙ d. PIN Diode
Last Answer : ∙ b. LED
Description : What is a specific path the light takes in an optical fiber corresponding to a certain angle and number of reflection ∙ a. Mode ∙ b. Grade ∙ c. Numerical Aperture ∙ d. Dispersion
Last Answer : a. Mode
Description : Is the different angle of entry of light into an optical fiber when the diameter of the core is many times the wavelength of the light transmitted. ∙ a. Acceptance angle ∙ b. Modes ∙ c. Sensors ∙ d. Aperture
Last Answer : b. Modes
Description : The law that states “When visible light of high frequency electromagnetic radiation illuminates a metallic surface, electrons are emitted” is known as ____________. ∙ A. Einstein law of photon ∙ B. Marconi’s law ∙ C. Maxwell’s law ∙ D. Plank’s law
Last Answer : D. Plank’s law
Description : Optical power is sometimes called __________. ∙ A. Radiant emission ∙ B. Radiant power ∙ C. Radiant flux ∙ D. Radiant optics
Last Answer : C. Radiant flux
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 : 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 : The term single mode and multimode are best described as ∙ A. a number of fibers placed into fiber-optic cable ∙ B. the number of voice channels each fiber can support ∙ C. the number of wavelengths each fiber can support ∙ D. the index number
Last Answer : C. the number of wavelengths each fiber can support
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 : 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
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 : 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 : 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 : 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 : 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 : 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 : 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 IC that represents a short distance one-way optical communications ∙ a. Optoisolator ∙ b. Insulator ∙ c. Multivibrator ∙ d. Optical IC
Last Answer : a. Optoisolator
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 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 : 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 : 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 : Which of the following is not part of the optical spectrum? ∙ a. Infrafed ∙ b. Ultraviolet ∙ c. Visible color ∙ d. X-rays
Last Answer : ∙ d. X-rays
Description : Which of the following is used as an optical receiver in fiber optics communications ∙ a. APD ∙ b. Tunnel diode ∙ c. Laser diode ∙ d. LED
Last Answer : a. APD
Description : Which of the following is used as an optical transmitter on the Fiber Optical Communications? ∙ a. APD ∙ b. LSA diode ∙ c. PIN diode ∙ d. LED
Last Answer : d. LED
Description : The bandwidth of optical fiber ∙ a. 900M Hz ∙ b. 900 PHz ∙ c. 900 THz ∙ d. 900 EHz
Last Answer : c. 900 THz
Description : The core of an optical fiber has a ∙ a. Lower refracted index than air ∙ b. Lower refractive index than the cladding ∙ c. Higher refractive index than the cladding ∙ d. Similar refractive index with the cladding
Last Answer : c. Higher refractive index than the cladding
Description : The dominant loss mechanisms in silica fiber are ∙ a. Absorption and radiation losses ∙ b. Absorption and Rayleigh scattering ∙ c. Coupling and radiation losses ∙ d. Radiation and modal dispersion
Last Answer : b. Absorption and Rayleigh scattering