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## Main Question or Discussion Point

Hello, I've recently been studying simple diffraction for an upcoming proficiency test, and in the lecture notes for the class, a simple equation regarding single-slit Fraunhoffer diffraction was derived. The derivation was a little weird, so as an exercise, I just decided to go ahead and use phasors to derive the formula myself. Anyway, when I was finished, I nearly had the exact same result as the notes, except for one thing: a factor of a, the width of the slit. Because I couldn't find my mistake anywhere, I decided to look up the result on Wikipedia, which I suspected would do it the same way that I did. Anyway, in the step where the factor of a in the denominator was introduced, there seems to be an integration error. Am I just missing something here?

[tex]= C \int_{-\frac{a}{2}}^{\frac{a}{2}}e^\frac{ikxx^\prime}{z} \,dx^\prime

=C \frac{\left(e^\frac{ikax}{2z} - e^\frac{-ikax}{2z}\right)}{\frac{2ikax}{2z}}[/tex]

[tex]= C \int_{-\frac{a}{2}}^{\frac{a}{2}}e^\frac{ikxx^\prime}{z} \,dx^\prime

=C \frac{\left(e^\frac{ikax}{2z} - e^\frac{-ikax}{2z}\right)}{\frac{2ikax}{2z}}[/tex]