CD Diffraction

CD diffraction:

In this experiment, we shine a laser on a cd and measure the reflected diffraction. This lets us calculate the size of the distance between the grooves of the CD.

using our laser, we first calculate the wavelength of our laser.

using our found values;

Using MATLAB:

>> properror(theta,[x y],[100 34],[1 1])

ans =

    [       0.3277]    '+/-'    [0.0095]

    'Percent Error'    '+/-'    [2.8888]

we calculate the wavelength to be 643 nm +_ 20nm

>> properror(theta,[x y],[50 25],[.2 .2])

ans =

    [       0.4636]    '+/-'    [0.0036]

    'Percent Error'    '+/-'    [0.7716]

theta = .4636 radians

We find the d, diffraction spacing of the CD:

>> properror(d,[theta lambda],[.4636 643],[.0036 .0095])

ans =

    [  1.4379e+003]    '+/-'    [10.3543]

    'Percent Error'    '+/-'    [ 0.7201]