1. 01The flash floods the surface with heat.
  2. 02Heat drains downward through the material.
  3. 03The air gap blocks that drain, so the surface above it stays warm.
  4. 04Shallow blooms early, deep blooms late. That timing is the depth measurement.

GT-1 instrument $8,500
Incumbent systems from $45,000

Cross sectionDefect boxed
Surface line scanWhat the camera reads