# Diffraction derivation on Wiki - wrong?

1. Jun 12, 2005

### jetpeach

Hey Everyone, anybody want to verify if what I believe is true- Wikipedia has an incorrect derivation for Fraunhoffer diffraction to calculate the intensity from a single slit.
http://en.wikipedia.org/wiki/Diffraction
The step I believe they "fudged" is the final integral under "Quantitative analysis of single-slit diffraction". The integral is from -a/2 to a/2 when they find it equal to (e^ikax/2z - e^-ikax/2z ) / (2ikax/2z). I believe this is the correct answer for this type of diffraction, but if I remember my integrals I can't see how they get the 'a' term in the denominator. Take a look, let me know what you think, if it really is wrong and somebody can correct the Wiki page, would they do so? (just click edit on the section) Or if we discuss it here and find it is in error, I'll correct it later.
Thanks! jet

2. Jun 12, 2005

### dextercioby

That C is arbitary and can be redefined as to factor "1/a"...

Daniel.