Image and coherence transfer in the stimulated down-conversion process

The intensity transverse profile of the light produced in the process of st imulated down-conversion is derived. A quantum-mechanical treatment is used . We show that the angular spectrum of the pump laser can be transferred to the stimulated down-converted beam, so that images can also be transferred from the pump to the down-converted beam. We also show that the transfer c an occur from the stimulating beam to the down-converted one. Finally, we s tudy the process of diffraction through an arbitrarily shaped screen. For t he special case of a double-slit, the interference pattern is explicitly ob tained. The visibility far the spontaneous emitted light is in accordance w ith the van Cittert-Zernike theorem for incoherent light, while the visibil ity for the stimulated emitted light is unity. The overall visibility is in accordance with previous experimental results.