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Re: [3810T] Screen is Flickering on low brightness

 

Am 28.12.2009 01:17, schrieb Michael:
Paul,

To my understanding, the backlight controller of all LED lit screens use high frequency flashing of the LEDs with different on-times, to adjust the (perceived) brightness. So for instance, at 100% brightness, LEDs are on at all times (no flickering). At 80% brightness, LEDs are flashing while being on for 80% of time and off for 20% of time. As the brightness decreases, the flickering increases. All that said, due to the high frequency of flashing, it's usually difficult to detect the flickering without paying special attention. If your screen is annoying you, there might be something wrong with it.

On Mon, Dec 28, 2009 at 11:03 AM, Pål Levold <paal.levold@xxxxxxxxx <mailto:paal.levold@xxxxxxxxx>> wrote:

    When I dim the brightness of my screen it starts flickering a bit
    when going below 34% (on the four lowest steps). It's a somewhat
    high frequent, small change in brightness so it's a bit hard to
    spot at once. The lower I set the brightness, the more significant
    it gets.
    Is this a hardware problem that occurs no matter what or is it
    something I can do to fix it? Anyone knows if this occurs in
    Windows too?

    Sincerely
    Paul



It's no problem on windows, but it's possible that windows doesn't go as far down with the brightness.

In linux it only occured to me on the lowest level so far. Much more noticable without the backlight=vendor line in the boot config (where you only have like 5 steps anyway).

What I however noticed on Windows is that they try to get more "dynamic" contrast using that nasty backlight trick, so depending on what's on the screen it might flicker because they try to improve the perceived contrast.
Best regards.

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