WHY RESOLUTION MATTERS
For x-ray & CT imaging there is a dynamic called Geometric Magnification. GeoMag (Mg) is the calculation of the distance between the x-ray source to test object and detector (Source to Object Distance, SOd) & (Source to Detector Distance, SDd).
If the detector remains stationary, the closer the object moves to the x-ray source the higher the resolution becomes. However, the further the object moves from the detector, the smaller the field of view. Put simply, the higher the resolution, the smaller the area of interest to be imaged.
A proper understanding of the project requirements determines the appropriate resolution and field of view. If a client needs to check for hairline fractures or micro-porosity, maximum resolution is necessary. If these defects are smaller than the resolution of the data they may not be resolved.
The below sensor is being scanned to evaluate potential leak paths in the soldered tip. The advantage of the 40um scan is that the entire part is characterized. However, the fine details of the area of interest are best resolved in an area of interest scan at 5x that resolution. At this resolution we can see micro-porosity not seen in the larger GeoMag scan.
40um Full Part Scan
8um Area of Interest Scan
