The passenger steps into a machine where he or she is quickly scanned with radio waves.

CNN: TSA trying new airline passenger screening machines

When a passenger steps forward to get on a flight, an agent could hold up the boarding pass and passport in front of their smart glasses, scanning barcodes on the two documents simultaneously.

BBC: Could Google Glass ease air travel?

Under new TSA guidelines, they point out, the person looking at the scanned image is in an entirely separate room, and the picture is deleted as soon as the next passenger steps into the scanner.

WSJ: Noah Shachtman: Has Airport Security Gone Too Far?