1. The problem statement, all variables and given/known data I need to derive the intensity distribution of the double slit experiment. Intensity as a function of the slit separation d, the distance to the screen L and the wavelength [itex]\lambda[/itex]. L>>d 2. Relevant equations 3. The attempt at a solution Ok this is ridiculous but everything I find is just telling me how to find the minimum or maximum. I also need to figure this out for the triple and N slit problems. I know that intensity is basically the square of the electric field. So I have been trying to make two waves and then add them together and then square them. I keep going wrong here. Is there an online resource that takes this approach?