1. The underlying technology works by identifying unique vein patterns in the human eye.

2. In the same vein, every pilot must also accept the input of their fellow crewmembers on the flight deck.

3. He even used the flashlight function on his smartphone to help her find a good vein for it, according to the defense.

4. In a more limited vein, Samsung has extended its software for recognizing a hovering stylus, to the human finger.