Optoelectronics and Laser Instrumentation Mid - I, September - 2014

1.The modulation band width being the frequency range between ________ & _________ Frequency.
  • one,3dB
  • zero, 0dB
  • zero,3dB
  • one, 0dB
Answer: C
2.p-i-n photo diode for operation in the shorter wavelength band below___________
  • 1.09μm
  • 1.08μm
  • 1.07μm
  • 1.06μm
Answer: A
3.APD works on the principle of ______________
  • Zener Breakdown
  • Zeeman effect
  • Avalanche Breakdown
  • Population Inversion
Answer: C
4.Ruby laser is a
  • two level laser system
  • three level laser system
  • four level laser system
  • five level laser system
Answer: B
5.YAG stands for
  • Y2AlO12
  • Y3Al4O11
  • Y3Al5O12
  • YAlO4
Answer: C
6.In He-Ne laser, helium atom tend to accumulate at levels F2 & F3 due to their long life times of
  • 10-4 & 5×10-6s
  • 10-3 & 4×10-4s
  • 10-2 & 3×10-3s
  • 10 & 2×10-4s
Answer: A
7.Output power of dye laser is
  • 2-4W
  • 3-6W
  • 2-5W
  • 1-4W
Answer: D
8.Excimer laser are tunable & emit mostly in
  • UV region
  • visible region
  • IR region
  • None
Answer: A
9.Pulsed telemeter are used to measure the distance
  • upto 50km
  • upto 100km
  • upto 150km
  • upto 200km
Answer: B
10.Pulsed compression technique has been demonstrated with
  • Argon laser
  • He-Ne laser
  • CO2 laser
  • Ruby laser
Answer: C
11.The responsivity is a useful parameter as it gives the transfer characteristic of the ___________
Answer: Detector
12.Group 3 & Group 5 semiconductor alloys have been employed in the fabrication of ____________ region detectors.
Answer: Longer wavelength
13.Drift time of carriers through the_____________, diffusion time of carriers generated____________
Answer: Depletion region, outside the depletion region
14.In light amplification N1>N2 means _____________ medium;N1
Answer: Attenuating, amplifying
15.The first gas laser to be operated successfully was the____________
Answer: He-Ne
16.Nd-YAG lasers find many applications in_____________ , ______________
Answer: Range finders, illuminators
17.The laser level is an extension of the concept of ______________
Answer: Point-like alignment
18.Laser level can be implemented by a _______________
Answer: Tripod-mounted laser
19.In order to measure α in triangulation method which instrument is used________________
Answer: Theodolite
20.Pulsed telemeters are useful for ______________ &_______________applications.
Answer: Geodesy research, military