Holography : Non-contact and optical non-destructive testing applications
Illustration
Figure 8 illustrates the appearance of fringes in real time when a composite membrane in which an adhesion defect is present is tested with a thermal source.
Figure 8 : Example of holograms in real time
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When the thermal constraint is increased the number of fringes increases until it is impossible to distinguish them because they are too tightly packed together as the image on the right shows.