Screen Locking
Using this module, you can determine how much time must pass before the screen locker is activated, and add or remove password protection to your screen locker.
At the top is a check box to have the screen locker Lock screen automatically after, and a spin box which determines the period of inactivity before the screen locker should be started. You can enter any positive number of minutes in this box.
Below that is a spinbox labeled Require password after locking. When you press a key or click a mouse button to end the screen locker after the time in the spinbox and return to your work, you must enter a password. The password used is the same password you used to login to your machine.
Locking the screen manually causes the password protection to engage immediately.
The default shortcut L provides a quick way to lock the screen manually.
Check Lock screen on resume if you want a password protected system when waking up from suspension.
If you would like to change the background in locked status switch to the Wallpaper tab.
You can select a Plain Color as wallpaper type.
Alternatively use a single image or a slideshow with images from a folder or load new wallpapers from the Internet.