Holographic interferometric investigations of plastic parts

Basic principles in the use of holographic interferometry for high-precision dimensional metrology on plastic shapes. Welded and adhesive bonded PVC sheets, PVC pipe junctions, galvanic coats, and orthotropic FRP sheets were examined nondestructively. Interference patterns are shown for melt-welded and sealed PVC and PE pipes. Faults built into the specimens were detected with ease, and unintended faults in the specimens were also clearly revealed. The geometry and density of the interference lines provide qualitative information on deformations caused by flaws in the product. Time-average and double-exposure holographic techniques were applied.