# The Kirchhoff diffraction formula with small wavelength

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1. Apr 18, 2017

### zhouhao

1. The problem statement, all variables and given/known data
The fresnel-kirchhoff diffraction formula could explain diffraction,I think it should also produce the result with relatively small wavelength and large width slit in which case there is no diffraction.

2. Relevant equations
$U(P)=\frac{ia}{2\lambda}\int_S\frac{e^{ik(s+r)}}{sr}[(cos(n,r)-cos(n,s)]dS$

3. The attempt at a solution
when $\lambda$(wavelength) is very small,the $U(P)$ would very large and seems not equal to $\frac{ae^ir_{P_0P}}{r_{P_0P}}$

Last edited: Apr 18, 2017
2. Apr 19, 2017