xbacklight does not work in Lubuntu 12.04

[cogitator]

And so I can not set the backlight of my monitor screen (for example, "xbacklight -set 50" does not make any effect, nor using the FN+F6 or FN+F7 keys does something). In 11.10 it was okay, but not now (in 12.04) is not. [My eyes hurts...!]

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: xbacklight 1.1.2-1
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic-pae 3.2.14
Uname: Linux 3.2.0-24-generic-pae i686
ApportVersion: 2.0.1-0ubuntu6
Architecture: i386
Date: Fri Apr 27 13:49:27 2012
EcryptfsInUse: Yes
ProcEnviron:
 TERM=xterm
 PATH=(custom, user)
 LANG=el_GR.UTF-8
 SHELL=/bin/bash
SourcePackage: xbacklight
UpgradeStatus: Upgraded to precise on 2012-04-27 (0 days ago)

[cogitator (bigdippergames)]

There should be a solution. I really can not comfortably use my pc with that problem in Lubuntu 12.04. All that strong light ...it is like being in a solarium! [There is a solution... to wear sunglasses, how's that...? Just kidding... but, really, you can not tolerate that.]

Well, if you are willing to help, do so -for the sake of Ubuntu.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[amjjawad  (amjjawad)]

Hi,

You are not alone, I too have the very same issue. I do have it on HP Pavilion dv6 - Core i5 and 4GB RAM - Lubuntu 12.04 64bit.

I can't look at the screen at all O_o

[amjjawad  (amjjawad)]

Not sure if this bug is fixed or not yet? and it seems that some machines are affected and some other are not!

[xhoch3 (xhoch3)]

Same thing happened to me. In my case xbacklight had a problem with choosing the right device in /sys/class/backlight/
To fix this I found a solution on https://wiki.archlinux.org/index.php?title=Backlight&oldid=310785#Backlight_fails_to_adjust_on_Intel_chipsets_with_Kernel_3.13

1. Create /etc/X11/xorg.conf.d/20-intel.conf
2. Put the following lines of code in there
Section "Device"
        Identifier "Backlight fix"
        Driver "intel"
        Option "Backlight" "intel_backlight"
EndSection