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My primary external IPS LED computer monitor is too bright, even when its hardware brightness is set to zero (0) and its contrast is turned down.

As such, I run a software tool that applies a translucent dark filter over the entire screen. This has 2 downsides:

  1. It requires some CPU power, which results in other tasks being slightly slower, increases energy usage, and increases noise due to increased use of fans.
  2. It wastes energy, as it doesn't actually reduce the display's backlight intensity.

For external LED computer displays, is there any way to reduce the brightness below zero (0)?

Answers that can be applied to Windows are preferred, but answers for all operating systems are welcome.

One option I've considered is applying a physical filter to the screen. My concern with doing this is reducing legibility of small text and possibly introducing more reflection.

Note: This question is intentionally similar to Precise backlight control on windows, except that question is specifically asking about internal screens within laptops.

RockPaperLz- Mask it or Casket
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  • Check that your system is properly set up and check with the monitor support site for advice on lowering brightness. I turn down my (internal) monitor and it goes to near black. – John Feb 16 '22 at 17:13
  • Do you need to retain colour accuracy? People usually go for IPS displays because they need an accurate display. If you're willing to abandon accuracy, you could start playing with gamma & target white point. Unless the manufacturer states differently, you can assume zero brightness is the lowest the LEDs can go. Everything else will be some form of 'masking' - like your overlay. – Tetsujin Feb 16 '22 at 17:24
  • @Tetsujin Thanks. Most of the time, I'm somewhat flexible regarding colour accuracy. The hue is important, but that's about it. For times when colour accuracy is critical, I am willing to change settings. I've was experimenting with gamma, and found that turning gamma up to 1.2 - 1.5 yields somewhat better results. I don't see a "target white point" setting anywhere. Could it have other names? – RockPaperLz- Mask it or Casket Feb 16 '22 at 17:56
  • I don't know the Windows structure well enough, but if you find it the units will be measure in degrees Kelvin [4,000 to 10,000], perhaps with some 'D' numbers too, D50, D65 etc. Basically it's a red/yellow/blue shift control. It won't affect actual brightness, but lower temperatures may be easier on the eye. – Tetsujin Feb 16 '22 at 18:26

1 Answers1

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If you need true control over the light output then ANY LCD/TFT/IPS screen is going to be useless. LEDs typically have minimum on levels and PWM used to dim them can also only go so far before it starts to show an obvious flicker and cause eye strain.

On a "normal" screen, even when it is black, it will still have a bright white light behind the darkened pixels. Some screens might turn off or selectively dim sections of the screen, but there is still some minimal back-light brightness.

Turning the display below 0 should in theory simply turn the back-light off. Not a big help there.

What you might want to look for is a true OLED panel, where the colour is generated by the pixels themselves without a bright light behind it. These should, in theory have more control of the low-light output.

Alternatively there are many options for privacy filters which can cover screens and dim the display as a side effect. Or simply buying a sheet of tinted material of the type you would use to tint car windows would probably achieve a similar effect.

RockPaperLz- Mask it or Casket
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Mokubai
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  • Thanks Mokubai. OLED is an interesting idea. I don't have buying a new screen in my budget right now, but it's a good idea for the future. With my IPS LED screen, if I were somehow able to turn off the backlight, would it make the screen completely worthless (meaning I wouldn't be able to see anything on it)? – RockPaperLz- Mask it or Casket Feb 16 '22 at 17:59
  • With the backlight off, you'd have to shine a torch at the front to attempt to see anything at all, but that would be … not a good look. ;) – Tetsujin Feb 16 '22 at 18:27
  • @RockPaperLz-MaskitorCasket the back-light is entirely what allows you to see anything at all. Without it you will have, at best, various shades of black ranging from a subtle reddish black, through to a nice shade of blueish black. LCD/IPS/LED (different from OLED) all act the same way as a screen projector does but instead of casting the image at a projector screen it is cast at you. It's all just bright light behind getting blocked or coloured by various elements in the way. No light, no image projected. – Mokubai Feb 16 '22 at 18:50
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    @Tetsujin Wait... I'm the only one who computes wearing a mining helmet with an affixed 18000 lumen task light? I thought that's how we all did it. ;) – RockPaperLz- Mask it or Casket Feb 16 '22 at 18:53
  • @Mokubai Thanks. That makes good sense. Not as funny as Tetsujin's comment, but very useful. ;) – RockPaperLz- Mask it or Casket Feb 16 '22 at 18:54