[Physics] Could airport security devices detect differences between printed and written documents


If airport security scanners of any kind (xray, thermal, whatever else they use) looked at two items:

  • A printed paper textbook
  • The same printed paper textbook into which we have inserted a regular folded US letter-sized paper with something written on it with a pencil, pen, marker, etc.

Could the security be able to detect the difference between the two?

Best Answer

No, it would look exactly the same as far as the x-ray is concerned.

Think x-ray passing through paper and ink.