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My laptop's screen is far too bright at night, even if I set it to minimum brightness. I know that it is capable of being dimmer, because Windows will dim it further if I leave it idle. However, I can't figure out how to dim it lower to minimum on Ubuntu. Is there a way?

I've looked at this question, but it's talking about Windows.

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If the back-light is set to the minimum, then that is all you can do with it. Try adjusting the brightness, contrast, and gamma of the video-card with something like xgamma or other program. –  Synetech Jan 3 '14 at 5:09

1 Answer 1

Here is a link specifically addressing setting screen brightness below the minimum:

Decrease Backlight Below Minimum – Ask Ubuntu

  1. Open Terminal

  2. Enter the following command:

    cat /sys/class/backlight/intel_backlight/brightness
  3. Write down the resulting value (12421 in my case)

  4. Divide value by 6 and write it down (2070 in my case)

  5. Enter the following in the terminal, replacing 2070 with your value:

    sudo su -c "echo 2070 >/sys/class/backlight/intel_backlight/brightness"
  6. Close Terminal

  7. For future usage of the last command, open Terminal, press Ctrl and R together, start typing brightness. When the last command appears, just press Enter.

It works for me on a Samsung NC110 with Ubuntu 12.04.

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That gives better control within the standard range. I want to go outside the standard range. –  cpast Mar 4 '13 at 6:05
For me, this dimmed the screen well past the minimum. :) (Lenovo Y50) –  Chris Cooper Dec 19 '14 at 4:31
Also worked great with 14.04 on acer E15. +1 –  Publi Design Mar 6 at 5:01

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