White light is used to illuminate the two slits in YDSE. The separation between the slits is b and the screen is at a distance d (>>b) from the slits. At a point on the screen directly in front of one of the slits, certain wavelengths are missing. Some of these missing wavelengths are
λ=b2d
λ=b23d
O1P=y=b2
Δx=S2P−S1P=ybd
=(b22)d=b22d
Wavelength are missing for,
Δx=λ12,3λ22,5λ32
λ1=2Δx=b2d,λ2=2Δx3=b23d,λ3=2Δx5=b25d