Description : What parameter of light detector determines the range or system length that can be achieved for a given wavelength? ∙ a. Transit time ∙ b. Spectral response ∙ c. Dark current ∙ d. Responsitivity
Last Answer : ∙ b. Spectral response
Description : A measure of conversion efficiency of a photodetector. ∙ A. Efficiency ∙ B. Responsivity ∙ C. Dark current ∙ D. Spectral response
Last Answer : B. Responsivity
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 range of wavelength values that a given photodiode will respond.
Last Answer : spectral response
Description : One of the following is not a characteristic of light detectors. ∙ a. Responsitivity ∙ b. Spectral response ∙ c. Transmit time ∙ d. Dispersion
Last Answer : ∙ d. Dispersion
Description : Is the width of the range of wavelengths emitted by the light source ∙ a. Bandwidth ∙ b. Chromatic Dispersion ∙ c. Spectral width ∙ d. Beamwidth
Last Answer : c. Spectral width
Description : Which of the following is the fastest light sensor? ∙ A. PIN photodiode ∙ B. Photovoltaic diode ∙ C. Photodiode ∙ D. Avalanche photodiode
Last Answer : Avalanche photodiode
Last Answer : D. Avalanche photodiode
Description : Which of the following is the fastest light sensor ∙ a. PIN photodiode ∙ b. Photovoltaic diode ∙ c. Phototransistor ∙ d. Avalanche photodiode
Last Answer : ∙ d. Avalanche photodiode
Description : Which of the following is NOT a common light detector ∙ a. PIN photodiode ∙ b. Photovoltaic diode ∙ c. Photodiode ∙ d. Avalanche photodiode
Last Answer : ∙ b. Photovoltaic diode
Description : What is the spectral width of an ILD? ∙ A. 0.1 nm to 1 nm ∙ B. 2 nm to 5 nm ∙ C. 1 nm to 3 nm ∙ D. 3 nm to 4 nm
Last Answer : C. 1 nm to 3 nm
Description : What is the spectral width of a standard LED? ∙ A. 20 to 40 nm ∙ B. 30 to 50 nm ∙ C. 10 to 30 nm ∙ D. 40 to 60 nm
Last Answer : 30 to 50 nm
Description : Dark current in light detectors is caused by ∙ a. Thermally generated carriers in the diode ∙ b. The absence of light input ∙ c. Small leakage current ∙ d. Its imperfection
Last Answer : a. Thermally generated carriers in the diode
Description : The band of light frequencies to which human eye will respond ∙ A. Infrared ∙ B. Visible light ∙ C. Ultraviolet ∙ D. Cosmic ray
Last Answer : B. Visible light
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 : The wavelength of a visible extends from ∙ A. 0.8 to 1.6 um ∙ B. 400 to 750 nm ∙ C. 200 to 660 nm ∙ D. 700 to 1200 nm
Last Answer : B. 400 to 750 nm
Description : A popular light wavelength fiber-optic cable is ∙ A. 0.7 micrometer ∙ B. 1.3 micrometer ∙ C. 1.5 micrometer ∙ D. 1.8 micrometer
Last Answer : B. 1.3 micrometer
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 : How many modes possible with a multimode step-index with a core diameter of 50 um, a core refractive index of 1.6, a cladding refractive index of 1.584, and a wavelength of 1300 nm. ∙ A. 456 ∙ B. 213 ∙ C. 145 ∙ D. 372
Last Answer : D. 372
Description : Infrared light has a wavelength that is ∙ A. less than 400 nm ∙ B. more than 700 nm ∙ C. less than 700 nm ∙ D. a little over 400 nm
Last Answer : B. more than 700 nm
Description : The higher the index number ∙ A. the higher the speed of light ∙ B. the lower the speed of light ∙ C. has no effect on the speed of light ∙ D. the shorter the wavelength propagation
Last Answer : B. the lower the speed of light
Description : Which of the following terms best describes the reason that light is refracted at different angles? ∙ A. Photon energy changes with wavelength ∙ B. Light is refracted as a function of surface smoothness ∙ ... determined partly by a and b ∙ D. The angle is determined by the index of the materials
Last Answer : ∙ D. The angle is determined by the index of the materials
Description : ange of wavelength of visible light ∙ A. 670 nm to 10^3 nm ∙ B. 440 nm to 540 nm ∙ C. 110 nm to 240 nm ∙ D. 390 nm to 770 nm
Last Answer : D. 390 nm to 770 nm
Description : What is the unit of light wavelength? ∙ a. Micrometer ∙ b. Angstroms ∙ c. Mils ∙ d. Fathom
Last Answer : ∙ b. Angstroms
Description : The bandwidth of a fiber is limited by ∙ a. Mode ∙ b. Wavelength ∙ c. Dispersion ∙ d. Frequency
Last Answer : c. Dispersion
Description : Modal dispersion is caused by the ∙ a. Dependence of wavelength on index of refraction ∙ b. Dependence of propagation constant on index of refraction ∙ c. Dependence of the propagation constant on the wavelength ∙ d. Dependence of the propagation constant on the mode number
Last Answer : d. Dependence of the propagation constant on the mode number
Description : Material dispersion is caused by the ∙ a. Wavelength dependence of the index of refraction ∙ b. Wavelength independence of the index of refraction ∙ c. Dependence of the propagation constant on the mode number ∙ d. Independence of the propagation constant on the mode number
Last Answer : d. Independence of the propagation constant on the mode number
Description : What is the typical wavelength of light emitted from epitaxially grown LEDs? ∙ a. 840 nm ∙ b. 490 nm ∙ c. 480 nm ∙ d. 940 nm
Last Answer : ∙ d. 940 nm
Description : A popular light wavelength in fiber-optic cable is ∙ a. 0.7 um ∙ b. 1.3 um ∙ c. 1.5 um ∙ d. 1.8 um
Last Answer : b. 1.3 um
Description : The wavelength of visible light extends from ∙ a. 0.8 to 1.0 nm ∙ b. 400 to 750 nm ∙ c. 200 to 660 nm ∙ d. 700 to 1200 nm
Last Answer : b. 400 to 750 nm
Description : The laser frequency when the light has the wavelength 800 nm is ∙ a. 375 x 1012 Hz ∙ b. 475 x 1015 Hz ∙ c. 375 x 109 Hz ∙ d. 375 x 1018 Hz
Last Answer : d. 375 x 1018 Hz
Description : ______ dispersion is caused by the difference in the propagation times of light rays that take different paths down a fiber. ∙ a. Material dispersion ∙ b. Wavelength dispersion ∙ c. Modal dispersion
Last Answer : ∙ c. Modal dispersion
Description : The wavelength of light has no role in ∙ a. Diffraction ∙ b. Interference ∙ c. Polarization ∙ d. Reflection
Last Answer : c. Polarization
Description : When a beam of light enters one medium from another, which quantity will not change? ∙ a. Direction ∙ b. Speed ∙ c. Frequency ∙ d. Wavelength
Last Answer : c. Frequency
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 : Which color has the shortest wavelength of light? ∙ a. Red ∙ b. Yellow ∙ c. Blue ∙ d. Green
Last Answer : c. Blue
Description : The magnetism left in the iron after exciting field has been removed is known as (a) permeance (b) residual magnetism (c) susceptance (d) reluctance
Last Answer : (b) residual magnetism
Description : Define reluctance and permeance with respect to magnetic circuit.
Last Answer : Reluctance: The opposition offered by magnetic circuit to establish magnetic flux in it, is called as “Reluctance”. Permeance: It is the reciprocal of reluctance and implies the magnetic core’s readiness with which magnetic flux is developed.
Description : Define the following terms: i) Magnetic flux density, ii) Reluctance, iii) Magneto-motive force, iv) Permeance.
Last Answer : (i) Magnetic flux density (B): It is the magnetic flux per unit area measured at right angles to the flux path. (Its unit is weber/m2 or tesla). (ii) Reluctance: It is the ... flux to set up through it and it is reciprocal of reluctance. Permeance = 1/ Reluctance. Unit: weber/ampere.
Description : The time it takes a light induced carrier travel across the depletion region of the semiconductor. ∙ A. dispersion ∙ B. response time ∙ C. irradiance ∙ D. transit time
Last Answer : D. transit time
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 : APD stands for: a. Avalanche Photodiode b. Advanced Photodiode c. Avalanche Photo Detector d. Advanced Photo Detector
Last Answer : a. Avalanche Photodiode
Description : Single-mode step-index cable has a core diameter in the range of ∙ A. 100 to 1000 micrometer ∙ B. 50 to 100 micrometer ∙ C. 2 to 15 micrometer ∙ D. 5 to 20 micrometer
Last Answer : . 2 to 15 micrometer
Description : Range of wavelengths of ultraviolet ∙ A. 670 nm to 10^3 nm ∙ B. 440 nm to 540 nm ∙ C. 110 nm to 240 nm ∙ D. 10 nm to 390 nm
Last Answer : D. 10 nm to 390 nm
Description : Range of infrared ∙ A. 360 nm to 440 nm ∙ B. 670 nm to 10^3 nm ∙ C. 110 nm to 240 nm ∙ D. 770 nm to 10^6 nm
Last Answer : D. 770 nm to 10^6 nm
Description : Infrared range for fiber optics ∙ a. 400 – 700 nm ∙ b. 700 – 1200 nm ∙ c. 300 – 2000 nm ∙ d. 400 – 7000 nm
Last Answer : b. 700 – 1200 nm
Description : Which laser emits light in the visible range 400 to 700 nm? ∙ a. Argon-ion ∙ b. Nitrogen ∙ c. Carbon-dioxide ∙ d. Neodymium-YAG
Last Answer : a. Argon-ion
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 : 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 : Ratio of the velocity of propagation of a light ray in free space to the velocity of propagation of a light ray in free space in a given material. ∙ A. refractive index ∙ B. standing wave ratio ∙ C. velocity factor ∙ D. propagation velocity
Last Answer : ∙ A. refractive index