Procedure for simulator
Controls
Start button: To start the experiment.
Switch on: To switch on the Laser.
Select Fiber: To select the type of fiber used.
Select Laser: To select a different laser source.
Detector distance (Z): Use the slider to vary the distance between the source and detector. (ie toward the fiber or away from the fiber.
Detector distance(x): Use the slider to change the detector distance i.e towards left or right w.r.t the fiber.
Show Graph: To Displays the graph.
Reset: To resets the experimental arrangement.
Preliminary Adjustment
- Drag and drop each apparatus in to the optical table as shown in the figure below.
Fig (4)
- Then Click “Start” button.
- Switch On (now you can see a spot in the middle of the detector)
- After that select the Fiber and Laser for performing the experiment from the control options.
To perform the experiment
- Set the detector distance Z (say 4mm). We referred the distance as “d” in our calculation.
- Vary the detector distance X by an order of 0.5mm, using the screw gauge (use up and down arrow on the screw gauge to rotate it).
- Measure the detector reading from output unit and tabulate it.
- Plot the graph between X in x-axis and output reading in y-axis. See figure 5.
- Find the radius of the spot r, which is corresponding to Imax/2.71 (See the figure 5).
Fig (5)
- Then find the numerical aperture of the optic fiber using the equation (4).
Observation column
SL No.
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Screw gauge reading
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Distance (X) mm
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I µA
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H.S.R
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P.S.R
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Calculations
Distance between the fiber and the detector, d = …………………………… m
Radius of the spot, r =……………………….. m
Numerical Aperture of the optic fiber, sin(θ) = = ..................
Acceptance angle, θ= = ...........................
Result
Numerical aperture of the optic fiber is = …………………
Angle of acceptance = ……………….