single and Dual Slit refraction

[PhysicsMan_2003]

Can someone give me the formulas for single a two slit defraction of light. And please explain what te variables mean.

Are these right? Wave length = xd/L

Wave length = yw/L
If these are right can someone please explain what the variable stand for because I am at a loss due to the fact that I have lost my notes
-thanks

[Claude Bile]

Intensity profile for 2 slits:

I1(x) + I2(x) + 2*sqrt(I1(x)*I2(x))*cos(delta)

Where

I1(x) = Intensity due to 1st slit
I2(x) = Intensity due to 2nd slit
delta = 2*pi*d/lambda

Where

d = distance between slits
lambda = Wavelength

I1(x) and I2(x) are gaussians i.e in the form Ae^(-(x-b)^2/a^2)
where A, b and a are constants determined by source intensity, slit width etc.

I have no idea what the equations you mentioned mean.

[PhysicsMan_2003]

Thanks a lot for your reply you really helped alot.