A device that was constructed from mirrors and selenium detectors that transmitted sound waves over a beam of light. ∙ A. lightphone ∙ B. photophone ∙ C. cameraphone ∙ D. walletphone

A device that was constructed from mirrors and selenium detectors that transmitted sound waves over a  beam of light.
∙ A. lightphone
∙ B. photophone
∙ C. cameraphone
∙ D. walletphone
by

1 Answer

Answer :

B. photophone
by

Related questions

Optical detectors are square-law devices because they respond to _____ rather than amplitude ∙ a. Intensity ∙ b. Light ∙ c. Density ∙ d. Photon

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

One of the following is not a characteristic of light detectors. ∙ a. Responsitivity ∙ b. Spectral response ∙ c. Transmit time ∙ d. Dispersion

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

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

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

A function of an optic isolator ∙ a. Cancels reflective waves ∙ b. Amplifies signal transmitted ∙ c. Filters unnecessary signals ∙ d. All of these

Description : A function of an optic isolator ∙ a. Cancels reflective waves ∙ b. Amplifies signal transmitted ∙ c. Filters unnecessary signals ∙ d. All of these

Last Answer : a. Cancels reflective waves

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

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

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 : 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

____ is a light that can be coherent ∙ a. Spontaneous emission ∙ b. Monochromatic and in-phase ∙ c. Narrow beam divergence ∙ d. Monochromatic

Description : ____ is a light that can be coherent ∙ a. Spontaneous emission ∙ b. Monochromatic and in-phase ∙ c. Narrow beam divergence ∙ d. Monochromatic

Last Answer : ∙ b. Monochromatic and in-phase

The first laser emitted ∙ a. Pulses of 694 nm red light ∙ b. A continuous red beam ∙ c. Pulses of white light from a helical flash lamp ∙ d. Spontaneous emission

Description : The first laser emitted ∙ a. Pulses of 694 nm red light ∙ b. A continuous red beam ∙ c. Pulses of white light from a helical flash lamp ∙ d. Spontaneous emission

Last Answer : ∙ a. Pulses of 694 nm red light

A dielectric waveguide for the propagation of electromagnetic energy at light frequencies ∙ a. Stripline ∙ b. Microstrip ∙ c. Laser beam ∙ d. Fiber optics

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

Dispersion is used to describe the ∙ a. Splitting of white light into its component colors ∙ b. Propagation of light in straight lines ∙ c. Bending of a beam of light when it goes from one medium to another ∙ d. Bending of a beam light when it strikes a mirror

Description : Dispersion is used to describe the ∙ a. Splitting of white light into its component colors ∙ b. Propagation of light in straight lines ∙ c. Bending of a beam of light when it goes from one medium to another ∙ d. Bending of a beam light when it strikes a mirror

Last Answer : a. Splitting of white light into its component colors

When a beam of light enters one medium from another, which quantity will not change? ∙ a. Direction ∙ b. Speed ∙ c. Frequency ∙ d. Wavelength

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

What generates a light beam of a specific visible frequency? ∙ a. Laser ∙ b. Maser ∙ c. Infrared ∙ d. Flashlight

Description : What generates a light beam of a specific visible frequency? ∙ a. Laser ∙ b. Maser ∙ c. Infrared ∙ d. Flashlight

Last Answer : ∙ a. Laser

Refraction is the ∙ A. bending of light ∙ B. reflection of light waves ∙ C. distortion of light waves ∙ D. diffusion of light waves

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

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 : 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

It is the science of measuring only light waves that are visible to the human eye. ∙ A. Radiometry ∙ B. Photometry ∙ C. Ophthalmology ∙ D. Optometry

Description : It is the science of measuring only light waves that are visible to the human eye. ∙ A. Radiometry ∙ B. Photometry ∙ C. Ophthalmology ∙ D. Optometry

Last Answer : B. Photometry

They wrote a paper describing how it was possible to use stimulated emission for amplifying light waves (laser) as well as microwaves (maser). ∙ A. Theodore Maiman ∙ B. KC Kao and GA Bockham ∙ C. Charles Townes and Arthur Schawlow ∙ D. Kapron, Keck and Maurer

Description : They wrote a paper describing how it was possible to use stimulated emission for amplifying light waves (laser) as well as microwaves (maser). ∙ A. Theodore Maiman ∙ B. KC Kao and GA Bockham ∙ C. Charles Townes and Arthur Schawlow ∙ D. Kapron, Keck and Maurer

Last Answer : C. Charles Townes and Arthur Schawlow

Refraction is the ∙ a. Bending of light waves ∙ b. Reflection of light waves ∙ c. Distortion of light waves ∙ d. Diffusion of light waves

Description : Refraction is the ∙ a. Bending of light waves ∙ b. Reflection of light waves ∙ c. Distortion of light waves ∙ d. Diffusion of light waves

Last Answer : a. Bending of light waves

As light is coupled in a multiport deflective device, the power is reduced by ∙ A. 1.5 dB ∙ B. 0.1 dB ∙ C. 0.5 dB ∙ D. 0.001 dB

Description : As light is coupled in a multiport deflective device, the power is reduced by ∙ A. 1.5 dB ∙ B. 0.1 dB ∙ C. 0.5 dB ∙ D. 0.001 dB

Last Answer : C. 0.5 dB

A coupler which consists of a series of lenses and a partly reflective surface ∙ a. Beam-splitting coupler ∙ b. Reflective star coupler ∙ c. Fused coupler ∙ d. None of these

Description : A coupler which consists of a series of lenses and a partly reflective surface ∙ a. Beam-splitting coupler ∙ b. Reflective star coupler ∙ c. Fused coupler ∙ d. None of these

Last Answer : ∙ a. Beam-splitting coupler

Longitudinal waves do not exhibit ∙ a. Polarization ∙ b. Refraction ∙ c. Reflection ∙ d. Diffraction

Description : Longitudinal waves do not exhibit ∙ a. Polarization ∙ b. Refraction ∙ c. Reflection ∙ d. Diffraction

Last Answer : a. Polarization

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

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

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

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

The main benefit of light-wave communications over microwaves or any other communications media is ∙ a. Lower cost ∙ b. Better security ∙ c. Wider bandwidth ∙ d. Freedom from interference

Description : The main benefit of light-wave communications over microwaves or any other communications media is ∙ a. Lower cost ∙ b. Better security ∙ c. Wider bandwidth ∙ d. Freedom from interference

Last Answer : c. Wider bandwidth

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 cone of acceptance should be filled with light. ∙ C. 70 percent of input light should be measured at the output. ∙ D. 70 percent of the unwanted wavelengths should be attenuated by the 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.

The speed of light in plastic compared to the speed of light in air is ∙ A. less ∙ B. more ∙ C. the same ∙ D. zero

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

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

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

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

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

A popular light wavelength fiber-optic cable is ∙ A. 0.7 micrometer ∙ B. 1.3 micrometer ∙ C. 1.5 micrometer ∙ D. 1.8 micrometer

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

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

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

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 output current to the input optical power ∙ C. the ratio of the input power to output power ∙ D. the ratio of output current to input current

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

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

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

The leakage current that flows through a photodiode with no light input ∙ A. dark voltage ∙ B. dark impedance ∙ C. dark power ∙ D. dark current

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

A pn-junction diode emits light by spontaneous emission ∙ A. LED ∙ B. APD ∙ C. PIN

Description : A pn-junction diode emits light by spontaneous emission ∙ A. LED ∙ B. APD ∙ C. PIN

Last Answer : A. LED

How can modal dispersion reduced entirely? ∙ A. Use a graded index fiber ∙ B. Use a single-mode fiber ∙ C. Use a monochromatic light source ∙ D. Use a very sensitive light detector

Description : How can modal dispersion reduced entirely? ∙ A. Use a graded index fiber ∙ B. Use a single-mode fiber ∙ C. Use a monochromatic light source ∙ D. Use a very sensitive light detector

Last Answer : Use a single-mode fiber

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

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

Chromatic dispersion can be eliminated by __________. ∙ A. using a monochromatic light source ∙ B. using a very small numerical aperture fiber ∙ C. using a graded-index fiber ∙ D. using a very sensitive photo detector

Description : Chromatic dispersion can be eliminated by __________. ∙ A. using a monochromatic light source ∙ B. using a very small numerical aperture fiber ∙ C. using a graded-index fiber ∙ D. using a very sensitive photo detector

Last Answer : A. using a monochromatic light source

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

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

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

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

It is caused by hydroxide ions in the material ∙ A. visible light absorption ∙ B. infrared absorption ∙ C. ultraviolet absorption ∙ D. ion resonance absorption

Description : It is caused by hydroxide ions in the material ∙ A. visible light absorption ∙ B. infrared absorption ∙ C. ultraviolet absorption ∙ D. ion resonance absorption

Last Answer : D. ion resonance absorption

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

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

It is caused by valence electrons in the silica material from which the fiber are manufactured. ∙ A. ion resonance absorption ∙ B. infrared absorption ∙ C. ultraviolet absorption ∙ D. visible light absorption

Description : It is caused by valence electrons in the silica material from which the fiber are manufactured. ∙ A. ion resonance absorption ∙ B. infrared absorption ∙ C. ultraviolet absorption ∙ D. visible light absorption

Last Answer : ultraviolet absorption

It is analogous to power dissipation to copper cables, impurities in the fiber absorb the light and covert it to heat. ∙ A. power loss ∙ B. absorption loss ∙ C. resistive loss ∙ D. heat loss

Description : It is analogous to power dissipation to copper cables, impurities in the fiber absorb the light and covert it to heat. ∙ A. power loss ∙ B. absorption loss ∙ C. resistive loss ∙ D. heat loss

Last Answer : B. absorption loss

Which of the following is not a factor in cable light loss? ∙ A. reflection ∙ B. absorption ∙ C. scattering ∙ D. dispersion

Description : Which of the following is not a factor in cable light loss? ∙ A. reflection ∙ B. absorption ∙ C. scattering ∙ D. dispersion

Last Answer : A. reflection

Results in reduction in the power of light wave as it travels down the cable. ∙ A. power loss ∙ B. absorption loss ∙ C. resistive loss ∙ D. heat loss

Description : Results in reduction in the power of light wave as it travels down the cable. ∙ A. power loss ∙ B. absorption loss ∙ C. resistive loss ∙ D. heat loss

Last Answer : A. power loss

More than one path for light rays to take down the fiber ∙ A. Multimode ∙ B. Step-index ∙ C. Single mode

Description : More than one path for light rays to take down the fiber ∙ A. Multimode ∙ B. Step-index ∙ C. Single mode

Last Answer : A. Multimode

Only one path for light rays to take down the fiber ∙ A. Multimode ∙ B. Step-index ∙ C. Single mode ∙ D. Graded index

Description : Only one path for light rays to take down the fiber ∙ A. Multimode ∙ B. Step-index ∙ C. Single mode ∙ D. Graded index

Last Answer : C. Single mode

The effect of a large magnitude of the numerical aperture ∙ A. The amount of external light the fiber will accept is greater. ∙ B. The amount of external light the fiber will accept is less. ∙ C. The amount of modal dispersion will be less. ∙ D. The amount of chromatic dispersion will be greater.

Description : The effect of a large magnitude of the numerical aperture ∙ A. The amount of external light the fiber will accept is greater. ∙ B. The amount of external light the fiber will accept is less. ... The amount of modal dispersion will be less. ∙ D. The amount of chromatic dispersion will be greater.

Last Answer : The amount of external light the fiber will accept is greater.

The maximum angle in which external light rays may strike the air/glass interface and still propagate down the fiber. ∙ A. Acceptance cone half-angle ∙ B. Acceptance cone ∙ C. Critical angle ∙ D. Angle of incidence

Description : The maximum angle in which external light rays may strike the air/glass interface and still propagate down the fiber. ∙ A. Acceptance cone half-angle ∙ B. Acceptance cone ∙ C. Critical angle ∙ D. Angle of incidence

Last Answer : A. Acceptance cone half-angle

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

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

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

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