Laser distance measurer

I got to play with a laser distance measurer. It fires a pulse of laser light at the wall and times how long it takes to come back. See below for the distance. You can shine it an angle.The light scatters a bit so no matter which angle you shine it, some comes back to the handset.

 It was more fun with a mirror where the scattering didn't work. So the laser light bounced off the mirror up to the ceiling, scattered from that and then back the way it had come, Impressive.