Non-coherent HSE

Non-coherent HSE takes place during illumination of recorded hologram with scattered light (Fig. 11b (2)). In this case, the 3-D hologram acts as a spatial filter which selects the light beams at the Bragg angle. Then, HSE occurs, as discussed above. However, for non-coherent HSE, the self-enhancement factor, $\xi$, is much smaller (for one or two orders) than for coherent HSE. Coherent and non-coherent HSE is a general phenomenon which occurs in any real time recording medium. This effect must be taken into account in real time optical recordings [19,2].