
Second Harmonic Generation Imaging196
ψ = = + + +uI u o ug or ug ro u r
o r o r
2 2
,
*
,
*
.
(9.3)
In the interesting case where the hologram is illuminated by a replica of the reference wave used for
its recording (u = r), the hologram would diract part of that light in a way that mimics the object wave.
is is illustrated in Figure 9.2a. By replacing u with r in Equation 9.3, one sees that the second term of
ψ
produces a replica of the object wave, weighted by the product of mutual coherence function with the
intensity of the reference wave. Consequently, an observer looking at the hologram along the direction
indicated by the viewpoint arrow wou ...