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Optics & resolution

2D vs 3D: choosing the right dimension

Not every problem needs 3D. Not every problem can be solved in 2D. The best solution is often a combination.

One of the biggest lessons in metrology is that the choice between 2D and 3D is not ideological.

2D captures appearance; 3D captures shape and height
2D is fast for appearance defects; 3D measures shape and height. The best systems often combine both.
  • Not every problem requires 3D.
  • Not every problem can be solved with 2D.
  • The best solution is often a combination of both.

How I decide

  • If the defect is defined by appearance (contrast, color, texture), 2D is usually faster and cheaper.
  • If the defect is defined by shape or height (coplanarity, dents, bond loops), you need 3D.
  • Many real systems use 2D to find candidates fast, then 3D to confirm or measure only where needed.
Combining modalities usually beats forcing one technique to do everything.