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Spatial coherence is a concept of wave disturbance describing the correlation between periodic transmitted energy (wave signals) from one point to another,it can also be said that it is a mutual interdependence or connection of variable wave quantities of two different points in a given instant of time,the coherence is presented as a function of distance ; the and mapped as correlation against an absolute distance between points in question.While spatial coherence is concerned with the phase correlation of waves in different observation points, temporal coherence entails the phase correlation of waves at a given point in space at two different instances of time.