Description : A mode filter is a device that attenuates specific modes propagating in the core of an optical fiber. What mode propagating along single mode fibers do mode filters eliminate?
Last Answer : Second-order mode.
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 single mode operation, the value of the normalized frequency (V) should remain near the 2.405 level. If the value of V is less than 1, do single mode fibers carry a majority of the power in the core or cladding material?
Last Answer : Cladding material.
Description : Explain the difference between multimode and single mode core-cladding concentricity errors.
Last Answer : Multimode core-cladding concentricity error is the distance between the core and cladding centers expressed as a percentage of core diameter while the single mode core-cladding concentricity error is just the distance between the core and cladding centers
Description : Give two reasons why optical fiber manufacturers depart from the traditional circular core and cladding, low-loss glass fiber design?
Last Answer : To increase performance and reduce cost
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 : The number of modes propagated in a multimode fiber depends on core size and numerical aperture (NA). If the core size and the NA decrease, will the number of modes propagated increase or decrease?
Last Answer : Decrease.
Description : How are source-to-fiber coupling and microbending and macrobending losses affected by changes in core diameter and D?
Last Answer : Coupling efficiency increases with both core diameter and D, while bending losses increase directly with core diameter and inversely with D.
Description : Will fiber coupling loss generally increase or decrease if the mode field diameter of a single mode fiber is decreased?
Last Answer : Increase.
Description : Low-order and high-order modes propagate along an optical fiber. How are modes determined to be low-order or high order modes?
Last Answer : Depends on the bending caused by the velocity difference of the wave traveling through different mediums
Description : The core of a fiber optic is surrounded by a. Wire braid shield b. Kevlar c. Cladding d. Plastic insulation
Last Answer : c. Cladding
Description : The inner portion of the fiber cable is called a. Cladding b. Coating c. Inner conductor d. Core
Last Answer : d. Core
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 core of the optical fiber has ______. A. A medium index of refraction B. A lower index of refraction than the cladding C. A lower index of refraction than air D. A higher index of refraction than the cladding
Last Answer : D. A higher index of refraction than the cladding
Description : ECE Board Exam March 1996 That dielectric material of an optical fiber surrounding the core A. Cladding B. Armor C. Shield D. Cover
Last Answer : A. Cladding
Description : ______ cables arecomposed ofa glass or plastic inner core surrounded by cladding, allencasedin an outside jacket. A) Coaxial B) Fiber-optic C) Twisted-pair D) none of the above
Last Answer : Fiber-optic
Description : ……cables are composed of a glass or plastic inner core surrounded by cladding,all encased in an outside jacket. a. Fiber-optic b. Coaxial c. Shield Twisted Pair d. Unshield Twisted-pair
Last Answer : a. Fiber-optic
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 : What phenomenon will result if the glass fiber is exposed to long periods of high humidity? ∙ A. stress fatigue ∙ B. core corrosion ∙ C. stress corrosion ∙ D. cladding corrosion
Last Answer : stress corrosion
Description : The three essential types of fiber commonly used today except: ∙ A. Plastic core and cladding ∙ B. Plastic core and glass cladding ∙ C. Glass core and glass cladding (SCS) ∙ D. Glass core and plastic cladding (PCS)
Last Answer : B. Plastic core and glass cladding
Description : ____ is applied to protect core and cladding of the fiber ∙ a. Insulation ∙ b. Fiber insulation ∙ c. Silica ∙ d. Polymer jacket
Last Answer : d. Polymer jacket
Description : The core of a fiber optic is surrounded by ∙ a. Wire braid shield ∙ b. Kevlar ∙ c. Cladding ∙ d. Plastic insulation
Last Answer : ∙ c. Cladding
Description : The inner portion of the fiber cable is called ∙ a. Cladding ∙ b. Coating ∙ c. Inner conductor ∙ d. Core
Last Answer : ∙ d. Core
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
Description : In fiber optics, higher-order mode refers to ∙ a. Cladding boundary at high angle ∙ b. Backscattering electromagnetic signals ∙ c. Diffracting signals ∙ d. All of these
Last Answer : ∙ a. Cladding boundary at high angle
Description : Multimode step-index fibers have a core and cladding of constant refractive index n1 and n2, respectively. Which refractive index, the core or cladding, is lower?
Last Answer : Cladding.
Description : Which fiber cladding, matched or depressed, consists of two regions?
Last Answer : Depressed.
Description : A light ray incident on the optical fiber core is propagated along the fiber. Is the angle of incidence of the light ray entering the fiber larger or smaller than the acceptance angle
Last Answer : Smaller.
Description : The mode theory uses electromagnetic wave behavior to describe the propagation of the light along the fiber. What is a set of guided electromagnetic waves called?
Last Answer : Modes of the fiber.
Description : Type of bend that occurs as a result of differences in thermal contraction rates between the core and the cladding material. ∙ A. Macrobending ∙ B. Microbending ∙ C. Quad bending ∙ D. Constant-radius bending
Last Answer : B. Microbending
Description : Type of bend that occurs as a result of differences in thermal contraction rates between the core and the cladding material.
Last Answer : Microbending
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 : 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
Description : Modes that are bound at one wavelength may not exist at longer wavelengths. What is the wavelength at which a mode ceases to be bound called?
Last Answer : Cutoff wavelength
Description : What four fiber properties determine the number of modes propagating in a multimode gradedindex fiber?
Last Answer : Numerical aperture (NA), relative refractive index difference ( D), profile parameter (α), and normalized frequency (V).
Description : Does underfilling a multimode optical fiber excite mainly high-order or low-order modes?
Last Answer : Low-order modes.
Description : Modes of a light pulse that enter the fiber at one time exit the fiber at different times. This condition causes the light pulse to spread. What is this condition called?
Last Answer : Modal dispersion.
Description : The fiber's normalized frequency (V) determines how many modes a fiber can support. As the value of V increases, will the number of modes supported by the fiber increase or decrease?
Description : Is coupling loss from fiber separation and lateral misalignment more critical in expanded-beam or butt-jointed connectors?
Last Answer : Butt-jointed connectors.
Description : Does coupling loss from refractive index profile difference result when the receiving fiber has a larger profile parameter
Last Answer : Fiber alignment.
Description : What is the basic fiber cleaving technique for preparing optical fibers for coupling?
Last Answer : Score-and-break.
Description : How does index matching gel affect the amount of coupling loss caused by (a) fiber separation, (b) lateral misalignment, and (c) angular misalignment?
Last Answer : (a) Reduces coupling loss, (b) does not change coupling loss, and (c) increases coupling loss
Description : What connection properties result in fiber optic connector coupling loss?
Last Answer : Poor fiber alignment and end preparation, fiber mismatches, and Fresnel reflection.
Description : In fiber-to-fiber connections, Fresnel reflection is one source of coupling losses. Light is reflected back into the source fiber and is lost. What causes Fresnel reflection?
Last Answer : A step change in refractive index that occurs at fiber joints, caused by fiber separation.
Description : Fiber-to-fiber coupling loss is affected by intrinsic and extrinsic coupling losses. Can intrinsic coupling losses be limited by limiting fiber mismatches?
Last Answer : Yes.
Description : The different angles of entry of light into an optical fiber when the diameter of the core is many times the wavelength of the light transmitter is known as ________. A. refraction B. sensor C. mode D. emitter
Last Answer : C. mode
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 : The core refractive index should be lesser than the cladding refractive index for a coaxial cable. State True/False a) True b) False
Last Answer : b) False
Description : The numerical aperture of a coaxial cable with core and cladding indices given by 2.33 and 1.4 respectively is a) 3.73 b) 0.83 c) 3.46 d) 1.86
Last Answer : d) 1.86