Draw for a 3d state all the possible orientations of theangular momentum vector L . What is Lx2 Ly2 forthe m/ 1 component?

1 Friday, November 13, 15 Diffraction and interference 2 Constructive Interference (1) § The geometric optics of the previous chapter cannot be used to explain interference § To understand these interference + phenomena we must take into account the wave nature of light § Interference takes place when light waves of the same wavelength are = superimposed § If the light waves are in phase, they interfere constructively, as shown to the right 14 Constructive Interference (2) § The statement that the two waves interfere constructively is the same as saying that the phase difference between the two waves is zero § A phase difference of 2π radians, 360° (one wavelength) will also produce two waves that are in phase § If the light waves are traveling from some common point, then the phase difference can be related to the path difference between the two waves § The criterion for constructive interference is given by a path difference Δx given by 15 Destructive Interference (1) § If the two light waves are out of phase, as shown to the right, the amplitudes of the waves will sum to + zero everywhere and the two waves will destructively interfere § Here the phase difference between the two waves is π = radi