For better power-savings from your computer display. Shut down your computer's display in an innovative way.

Computer Operating Systems typically try to save power by turning off the display after some keyboard/mouse activity timeout: maybe 10 minutes. Wouldn't it be better if the computer actually knew when you were at the computer and when you have left?

Sonar Power Manager use a new user presence detection technique to shut off the computer display when you are not present. It was developed by myself and other researchers at Northwestern University and University of Michigan. The goal is to shut off the screen immediately after you leave, even if you just moved the mouse 10 seconds ago.

The Sonar Power Manger uses ultrasonics (sound above 20kHz in frequency and which humans cannot hear) on your computer's regular sound system. Surprisingly, we have found that many laptops can use ultrasonics. However, many laptops cannot. For these unlucky users, the Sonar Power Manager will not properly detect user presence. Other unlucky users will find that their speakers produce annoying lower-frequency harmonics or noise while the sonar is operating.

Compatibility
1. The software works on MS Windows (2000, XP, Vista, 7) and also on Linux. However, to use it on Linux you must compile from source.
2. Hardware requirements include speakers and a microphone; these are built into most modern laptop computers.

The license of this software is Freeware, you can free download and free use this shutdown software.