Fraunhofer diffraction and Fourier Transform

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SUMMARY

The discussion focuses on comparing an experimentally obtained single slit diffraction pattern with the theoretical results derived from a Discrete Fourier Transform (DFT) in MATLAB. The slit width is specified as 0.000134 m. The MATLAB code provided calculates the diffraction pattern using the sinc function, but the user seeks guidance on accurately comparing the width of the central maxima between the experimental and theoretical results, particularly regarding the inclusion of the light wavelength in the calculations.

PREREQUISITES
  • Understanding of Fraunhofer diffraction principles
  • Familiarity with MATLAB programming and plotting
  • Knowledge of the Discrete Fourier Transform (DFT)
  • Basic concepts of wave optics and sinc functions
NEXT STEPS
  • Modify the MATLAB code to include the wavelength of light in the calculations for accurate diffraction pattern comparison
  • Research the impact of slit width on the diffraction pattern and central maxima width
  • Learn about the relationship between spatial frequency and diffraction patterns in optics
  • Explore advanced MATLAB functions for performing Discrete Fourier Transforms
USEFUL FOR

Students and researchers in optics, particularly those studying wave phenomena and diffraction patterns, as well as MATLAB users seeking to enhance their understanding of Fourier analysis in experimental physics.

bcjochim07
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Homework Statement


In lab, I obtained a single slit diffraction pattern and recorded an image of it. The slit width is known to be 0.000134 m. We are supposed to compare our experimentally-obtained diffraction pattern to the result of taking a Discrete Fourier Transform of the aperture in MATLAB.


Homework Equations





The Attempt at a Solution



Here is my MATLAB code:

E=[-100000:25:100000];
F=zeros(1,8001);
for n=1:8001;
F(n)=0.000134*(sin(pi*0.000134*E(n)))/(pi*0.000134*E(n));
end;
plot(E,abs(F))

Here, E corresponds to spatial frequency (m^-1). I'm plotting the power spectrum as a function of E. Qualitatively, the MATLAB result looks very similar to the experimental result, as one would expect. But can I compare the width of the central maxima? At first, I thought that maybe taking the reciprocal of the width of the central max. of the MATLAB result would yield the same width as I saw experimentally. But then again, I'm not taking into account the wavelength of the light in the code. How could I modify my code to give an accurate comparison?
 
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I guess I'm technically not taking the Discrete Fourier transform but just plotting what I know the Fourier transform should be based on F.T. pairs.
 
Any suggestions?
 

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