By default Raspbian has two things that make the screen blank: Screensaver and HDMI blanking. To remedy this we have to edit two files: LXDE’s autostart programs and kbd’s configuration.

The screensaver (xscreensaver) is bundled with the LXDE desktop and is autostarted by default. The HDMI output is subject to kbd and is due to the default configuration being powered down after 30 minutes of inactivity.

Disabling screensaver and configuring x11 options

Begin by installing the x11-server-utils if they’re not already installed.

[shell]raspberry@pi:~$ sudo apt-get install x11-xserver-utils[/shell]

Now we need to edit the autostart file

[shell]raspberry@pi:~$ sudo nano /etc/xdg/lxsession/LXDE-pi/autostart[/shell]

Find and remove the line @xscreensaver -no-splash.

Add the following, each on a separate line:

@xset s noblank
@xset s off
@xset -dpms

Save and exit the file (ctrl + x, then y)

[shell gutter=”true”]raspberry@pi:~$ sudo nano /etc/kbd/config[/shell]

Find and edit the following sections in the file so they look like below:

BLANK_TIME=0
BLANK_DPMS=off
POWERDOWN_TIME=0

Now just restart the raspberry pi or run:

[shell gutter=”true”]
raspberry@pi:~$ sudo pkill xscreensaver
raspberry@pi:~$ sudo service kbd restart
raspberry@pi:~$ export DISPLAY=:0; xset s noblank; xset s off; xset -dpms[/shell]

That should do the trick!