Optical Coherence Measurement Fundamentals for Deep Tooling Cavities
Optical coherence measurement uses broad-bandwidth infrared interference to capture deep cavity topographies without mechanical probe contact or lens clipping.
CAD Deviation Mapping
Meaning
Inspection methodology comparing physical scan data to digital nominal models. In polymer injection molding, cad deviation mapping provides a heat map of dimensional variance across complex surfaces. This process identifies areas of excessive shrinkage or tool deflection that standard calipers cannot capture.
Inspection Accuracy
Precision measurement depends on the alignment of the point cloud to the master file. Using cad deviation mapping allows quality engineers to visualize warpage patterns in thin walled sections. These color coded overlays show exactly where the part pulls away from the designed geometry.
Tool Correction
Adjusting the steel requires high resolution feedback from the first shots during the sampling phase. When a mold produces parts with consistent localized errors, cad deviation mapping guides the machinist toward the specific coordinates needing adjustment. This eliminates the trial and error associated with manual profile checking because the software isolates the global shift from local defects.
Precise milling paths are then derived directly from the delta between the scan and the model.
Process Stability
Consistency across batches remains the primary goal of any high volume production run. Engineers apply cad deviation mapping during validation to confirm that cycle time changes do not introduce non linear deformations. One shift in cooling rate can alter the entire surface profile.