Description : The _____ of a detector is the fraction of incident photons that produce a photoelectron or electron-hole pair ∙ a. Responsitivity ∙ b. Photon efficiency ∙ c. Aperture ∙ d. Quantum efficiency
Last Answer : d. Quantum efficiency
Description : t is a result of photons of light that are absorbed by the atoms of the glass core molecule. ∙ A. ion resonance absorption ∙ B. infrared absorption ∙ C. ultraviolet absorption ∙ D. visible light absorption
Last Answer : B. infrared absorption
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 : ________ is the result of photons of light that are absorbed by the atoms of the glass core molecules ∙ a. Ion resonance absorption ∙ b. Ultraviolet absorption ∙ c. Infrared absorption ∙ d. Absorption loss
Last Answer : c. Infrared absorption
Description : Which theory states that the light wave behaves as if it consists of many tiny particles? ∙ a. Huygen’s theory ∙ b. Wave theory of light ∙ c. Nyquist theory ∙ d. Quantum theory
Last Answer : ∙ d. Quantum theory
Description : Total internal reflection takes place if the light ray strikes the interface at an angle with what relationship to the critical angle? ∙ A. less than ∙ B. greater than ∙ C. equal to ∙ D. zero
Last Answer : ∙ B. greater than
Description : Between silicon and gallium arsenide, which has the greatest index of refraction? ∙ A. Gallium arsenide ∙ B. Neither of silicon nor gallium arsenide ∙ C. Silicon ∙ D. They are equal
Last Answer : Gallium arsenide
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 : Total internal reflection takes place if the light ray strikes the interface at an angle with what relationship to the critical angle? ∙ a. Less than ∙ b. Grater than ∙ c. Equal to ∙ d. Zer
Last Answer : ∙ b. Grater than
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 : The process of moving from one energy level to another is called ____________. ∙ A. Spontaneous emission ∙ B. Excited emission ∙ C. Absorption ∙ D. Spontaneous decay
Last Answer : C. Absorption
Description : The process of decaying from one energy level to another energy level is called __________. ∙ A. Spontaneous emission ∙ B. Excited emission ∙ C. Absorption ∙ D. Any of these
Last Answer : A. Spontaneous emission
Description : Any energy above the ground state is called ___________. ∙ A. normal state ∙ B. above-ground state ∙ C. excited state ∙ D. spontaneous state
Last Answer : D. spontaneous state
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 : The energy of the photon is ∙ a. Directly proportional to its bandwidth ∙ b. Directly proportional to the Planck’s constant ∙ c. Directly proportional to Boltzmann’s constant ∙ d. Inversely proportional to the Planck’s constant
Last Answer : Directly proportional to the Planck’s constant
Description : Which of the following factor does not harm laser efficiency? ∙ a. Atmospheric absorption ∙ b. Excitation energy not absorbed ∙ c. Problems in depopulating the lower laser level ∙ d. Inefficiency in populating the upper laser level
Last Answer : ∙ a. Atmospheric absorption
Description : What is the photon energy for an infrared wave with frequency of 1012 Hz? ∙ a. 10.6 x 1034 joules ∙ b. 6.63 x 10-34 joules ∙ c. 6.63 x 10-22 joules ∙ d. 10.6 x 1022 joules
Last Answer : ∙ c. 6.63 x 10-22 joules
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 dielectric waveguide for the propagation of electromagnetic energy at light frequencies ∙ a. Stripline ∙ b. Microstrip ∙ c. Laser beam ∙ d. Fiber optics
Last Answer : d. Fiber optics
Description : It is caused by the difference in the propagation time of light rays that take different paths down the fiber. ∙ A. modal dispersion ∙ B. microbending ∙ C. Rayleigh scattering ∙ D. chromatic dispersion
Last Answer : A. modal dispersion
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 quantum of light is called the ____________________.
Last Answer : photon
Description : The quantum of light is called: a. an erg b. an e-v c. a photon d. a phonon
Last Answer : c. a photon
Description : The minimum angle of incidence at which the light ray may strike the interface of two media and result in an angle of refraction of 90 degrees or greater. ∙ A. optimum angle ∙ B. angle of refraction ∙ C. refracted angle ∙ D. critical angle
Last Answer : D. critical angle
Description : Under normal condition, a single fiber should not be used for a two-way communication mainly because of ∙ a. Loss ∙ b. Fading ∙ c. Noise ∙ d. Attenuation
Last Answer : ∙ c. Noise
Description : It refers to the abrupt of change in refractive index from core to clad ∙ A. step index ∙ B. graded index ∙ C. semi-graded index ∙ D. half step index
Last Answer : ∙ A. step index
Description : The term power budgeting refers to ∙ A. the cost of cable, connectors, equipment and installation ∙ B. the loss of power due to defective components ∙ C. the total power available minus the attenuation losses ∙ D. the comparative costs of fiber and copper installations
Last Answer : C. the total power available minus the attenuation losses
Description : Which type of fiber-optic cable is the most widely used? ∙ A. single-mode step-index ∙ B. multimode step-index ∙ C. single-mode graded index ∙ D. multimode graded index
Last Answer : B. multimode step-index
Description : Which of the following cables will have the highest launch power capability? ∙ A. 50/125/0.2 ∙ B. 85/125/0.275 ∙ C. 62.5/125/0.275 ∙ D. 100/140/0.3
Last Answer : A. 50/125/0.2
Description : Refraction is the ∙ A. bending of light ∙ B. reflection of light waves ∙ C. distortion of light waves ∙ D. diffusion of light waves
Last Answer : A. bending of light
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 : 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 : 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 main benefit of light wave communications over microwaves or any other communications media are ∙ A. lower cost ∙ B. better security ∙ C. wider bandwidth ∙ D. freedom from interface
Last Answer : C. wider bandwidth
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 : Which of the following is not a major benefit of a fiber-optic cable? ∙ A. immunity from interference ∙ B. no electrical safety problems ∙ C. excellent data security ∙ D. lower cost
Last Answer : ∙ D. lower cost
Description : The speed of light in plastic compared to the speed of light in air is ∙ A. less ∙ B. more ∙ C. the same ∙ D. zero
Last Answer : A. less
Description : The core of fiber-optic cable is surrounded by ∙ A. wire braid shield ∙ B. Keviar ∙ C. cladding ∙ D. plastic insulation
Last Answer : ∙ C. cladding
Description : The core of a fiber-optic cable is made of ∙ A. air ∙ B. glass ∙ C. diamond ∙ D. quartz
Last Answer : B. glass
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 : The mechanical splice is best suited for ∙ A. quicker installation under ideal condition ∙ B. minimum attenuation losses ∙ C. field service conditions ∙ D. situations in which cost of equipment is not a factor
Last Answer : D. situations in which cost of equipment is not a factor
Description : Which cable length has the highest attenuation? ∙ A. 1 km ∙ B. 2 km ∙ C. 95 ft. ∙ D. 500 ft.
Last Answer : B. 2 km
Description : Cable attenuation is usually expressed in terms of ∙ A. loss per foot ∙ B. dB/km ∙ C. intensity per mile ∙ D. voltage drop per inch
Last Answer : . dB/km
Description : Which of the following is not a common type of fiber-optic cable? ∙ A. single-mode step-index ∙ B. multimode graded-index ∙ C. single-mode graded-index ∙ D. multimode step-index
Last Answer : . single-mode graded-index
Description : The operation of a fiber-optic cable is based on the principle of ∙ A. refraction ∙ B. reflection ∙ C. dispersion ∙ D. absorption
Last Answer : A. refraction
Description : Loss comparisons between fusion splices an mechanical splices ∙ A. 1:10 ∙ B. 10:1 ∙ C. 20:1 ∙ D. 1:20
Last Answer : A. 1:10
Description : Which of the following is not a common application of fiber-optic cable? ∙ A. computer networks ∙ B. long-distance telephone system ∙ C. closed-circuit TV ∙ D. consumer TV
Last Answer : ∙ D. consumer TV
Description : Type of lasers that are made from semiconductor ph-junctions commonly called ILDs ∙ A. semiconductor lasers ∙ B. liquid lasers ∙ C. plasma lasers ∙ D. gas lasers
Last Answer : semiconductor lasers
Description : Type of lasers that use solid, cylindrical crystals such as ruby ∙ A. solid lasers ∙ B. ILD ∙ C. gas lasers ∙ D. liquid lasers
Last Answer : ∙ A. solid lasers