Current alternative to W-LED backlighting?

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partikl

Limp Gawd
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Aug 10, 2017
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I think that W-LED is the issue with backlight bleed through. I have an old RGB-LED monitor that does not have nearly as much backlight bleed through as any W-LED backlit monitor I have seen. And I think the limited light spectrum and high intensity of W-LED (and the bleed through) is a major factor in eye fatigue.

What are the current backlight alternatives for practical desktop monitors (27" or smaller)?
 
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The type of LEDs used shouldn't have an effect on backlight bleed. That has to do with assembly, LED backlight arrangement (edge-lit vs. full array), panel type, and panel quality.
 
What I am calling bleed through is not edge bleeding. It is overall backlight bleed through or glow. I guess more people call it IPS glow. But it isn't only a problem with IPS panels. It is a problem with IPS, VA, and TN. In other words, it is a W-LED backlight problem, not a panel type problem. OLED is the only current display type I have seen where it is not a major problem. Any way, I should probably call it W-LED glow since it affects all panel types that use W-LED backlighting.

Last night at work, where there is a mix of many old and newer monitors, I noticed an old TN monitor where the backlight glow was minimal. It was almost as if the monitor was off (black background, nothing but a white mouse cursor), and it was much better than any current monitor that I have seen (except OLED) and most likely because it uses CCFL backlighting. An old monitor of mine that uses RGB-LED backlighting also has much less backlight glow than any current monitor I have seen.

The backlight intensity of W-LED is just way overboard if you ask me. It makes the panel glow even when the image on display is solid black. And white elements (such as white text on black background) glows so much that fonts have small streamers coming off of them, even with the brightness turned down. And of course when the brightness is turned way down to try and mitigate the glow, the picture suffers badly, often looking dim and washed out.
 
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partikl said:
What I am calling bleed through is not edge bleeding. It is overall backlight bleed through or glow. I guess more people call it IPS glow. But it isn't only a problem with IPS panels. It is a problem with IPS, VA, and TN. In other words, it is a W-LED backlight problem, not a panel type problem. OLED is the only current display type I have seen where it is not a major problem. Any way, I should probably call it W-LED glow since it affects all panel types that use W-LED backlighting.

Last night at work, where there is a mix of many old and newer monitors, I noticed an old TN monitor where the backlight glow was minimal. It was almost as if the monitor was off (black background, nothing but a white mouse cursor), and it was much better than any current monitor that I have seen (except OLED) and most likely because it uses CCFL backlighting. An old monitor of mine that uses RGB-LED backlighting also has much less backlight glow than any current monitor I have seen.

The backlight intensity of W-LED is just way overboard if you ask me. It makes the panel glow even when the image on display is solid black. And white elements (such as white text on black background) glows so much that fonts have small streamers coming off of them, even with the brightness turned down. And of course when the brightness is turned way down to try and mitigate the glow, the picture suffers badly, often looking dim and washed out.
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Sorry, don't see what you're talking about with any of the monitors that I use. Sounds like the monitors you're talking about need to be properly calibrated. A display properly calibrated at 100 nits will not appear washed out.
 
I think you're talking about backlight uniformity.

The problem is the light source is on the edge of the display, or wherever they put it, but they have to evenly distribute it to each pixel.
The more light sources they have the easier it is to do. So "full array local dimming" high end displays have less noticable issues.

It's always noticable if you look close enough though.

The only way to fix it is have a massive backlight that fits the entire screen and outputs the exact same brightness all over, or each pixel gets it's own backlight.
 
sharknice said:
I think you're talking about backlight uniformity.

The problem is the light source is on the edge of the display, or wherever they put it, but they have to evenly distribute it to each pixel.
The more light sources they have the easier it is to do. So "full array local dimming" high end displays have less noticable issues.

It's always noticable if you look close enough though.

The only way to fix it is have a massive backlight that fits the entire screen and outputs the exact same brightness all over, or each pixel gets it's own backlight.
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No, I am not talking about uniformity. And I am not talking about edge bleed. I am talking about overall panel glow from the backlight. The worst glow I have seen has been on W-LED IPS monitors where a black screen can look light grey or dark purple under low light. On the VA monitor that I am trying out, with the room lights off and a completely black screen, there is still enough backlight glow to illuminate the room just well enough to be able to navigate the room, with the panel having a sort of greyish look.
 
Armenius said:
Sorry, don't see what you're talking about with any of the monitors that I use. Sounds like the monitors you're talking about need to be properly calibrated. A display properly calibrated at 100 nits will not appear washed out.
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I can very easily see it on any W-LED monitor, even with the brightness turned all the way down. Your monitors must be made of magic dust and unicorns. ;)

Or maybe I have an unrecognzied super power for seeing light through objects.

Neither case is very likely.
 
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Okay, you're actually talking about the intrinsic inability of LCD to fully block light, not backlight bleed or IPS glow specifically. The only thing you can really do about this is to lower the brightness of the display. Otherwise, panels with higher contrast ratios will help, but some degree of automatic backlight dimming will do the most (especially FALD).
 
Glow on CCFL backlit panels and LED backlit panels is the same.
Where difference lies is most probably native backlight color temperature. CCFL's had usually natively 6500K and got more yellow over time. There exist W-LEDs with 6500K but many of them are much more blue and blue is terrible for black presentation. Yellow is also bad but less intrusive. As a general rule you want black temperature to match white temperature exactly. So any display you use should have 6500K white with 100% red, 100% green and 100% blue set in monitor OSD/service_menu. Many monitors without 6500K backlight will reduce blue to achieve D65 whitepoint.

HP LP2480zx always have the same color for black and white because RGB-LED backlight can change colors so unlike basically any other professional monitor it will have 100% of its contrast ratio no matter how you calibrate it. It also have A-TW polarizer to elliminate off-angle glow and digital uniformity correction so brightness is pretty uniform across the screen. It also have direct backlight vs edge lit like in most monitors and this by itself improves off-angle glow. When it comes to SDR image quality it is the best monitor money can buy except OLEDs which will have better blacks.

Acer XB271HK which I use for desktop and games have close to 6500K backlight and black is thus also 6500K. It have off-angle glow (IPS glow) but this is only visible on sides or rather corners. Most of the screen have very similar contrast ratio as LP2480zx. Colors are worse and gamma cannot be set to higher than 2.2 (which is bad for videos) and motion clarity is visibly worse but generally I am satisfied with its image quality for what it is. If it had blueish pale look to it like some other W-LED monitors including Dell you mentioned in other thread I would return it as soon as I got it.
 
XoR_ said:
HP LP2480zx always have the same color for black and white because RGB-LED backlight can change colors so unlike basically any other professional monitor it will have 100% of its contrast ratio no matter how you calibrate it. It also have A-TW polarizer to elliminate off-angle glow and digital uniformity correction so brightness is pretty uniform across the screen. It also have direct backlight vs edge lit like in most monitors and this by itself improves off-angle glow. When it comes to SDR image quality it is the best monitor money can buy except OLEDs which will have better blacks.
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It's really too bad that manufacturers didn't further pursue RGB-LED and A-TW polarizers. I think it has alot going for it. But in the case of the LP2480ZX the PWM is not nice, and the requirement for a custom calibrator (lacking even basic OSD adjustments, as with every other monitor) leaves this monitor back in it's day, if such a design decision ever had it's day.
 
Necere said:
Okay, you're actually talking about the intrinsic inability of LCD to fully block light, not backlight bleed or IPS glow specifically. The only thing you can really do about this is to lower the brightness of the display. Otherwise, panels with higher contrast ratios will help, but some degree of automatic backlight dimming will do the most (especially FALD).
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This except he's also right that CCFL produces more consistent results.
That's cause Edge LED is distributed in strips while CCFL is just a rigid tube, so you can't mount it wrong and it doesn't react badly to pressure.
The only place where this doesn't happen is where there's an A-TW polarizer. The most common device with those are macbook pros.
 
Keller1 said:
This except he's also right that CCFL produces more consistent results.
That's cause Edge LED is distributed in strips while CCFL is just a rigid tube, so you can't mount it wrong and it doesn't react badly to pressure.
The only place where this doesn't happen is where there's an A-TW polarizer. The most common device with those are macbook pros.
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Do you know which macbook pros use a A-TW polarizer?
 
partikl: I've used MacBookPros as well as the most recent 5K Cinema Display from LG which was over 1000 EUR and they were both unusable in the long run. From what you wrote you seem to suffer W-LEDs just as I do. I still have a few CCFL-backlit monitors stacked to be able to work. I can read white text on gray background on CCFL-backlit monitor just fine. Any W-LED backlit display and white fonts have so much glare it feels like looking at a street lamp at night. Up until recently I wasn't sure why my eyes burn after using W-LED backlit displays. Then I've read this article which seems to explain the process very well: http://texyt.com/bright+blue+leds+annoyance+health+risks . For he past 5 years I have been testing various *LED backlit based displays and I haven't found anything as comfortable as CRT/CCFL. Haven't tried OLED but it might suffer from PWM issues.
 
deviant, tell me about it. And staring into these W-LED's for hours every day is terrible for the eyes. I don't care what anyone says. I never had any issues with computer monitors until W-LED backlighting came about. I have been permanently affected as I'm sure many other people have.

What really gets me is that there are no monitors today designed to address the primary concern of working with text. It's all about video and gaming. Brighter and more vibrant...and killing our eyes. I want a monitor that is comfortable for working with text.

I have found VA to be somewhat more comfortable, but it sure isn't an end all to the issue. When I look at my current VA monitor it doesn't look blue at all. I have it set up to look warm. But if I spend 10 minutes outside in the day sun and come back in, it sure does have a blue tint to it, although nothing on par with what I see at work. And it can't be completely adjusted out. And no W-LED display that I have seen can practically have the blue tint adjusted out. Other colors being mixed in helps to mask it, but it's still there.
 
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Ever tried to video chat with someone who wears glasses and sits in a dark room? Pay attention to the reflections in their glasses. Even if they have youtube open or any other website with white background, you will notice the screen reflection is all blue. This pretty much shows you the amount of blue light that most people's eyes are trying to fight against and focus on. Most people with bad vision are ok with LED backlit displays. Usually the better the eye sight the worse it gets when you try to look at blue light halo. You can see a good comparison of LED to CCFL here: https://pcmonitors.info/articles/the-evolution-of-led-backlights/
 
deviant said:
Ever tried to video chat with someone who wears glasses and sits in a dark room? Pay attention to the reflections in their glasses. Even if they have youtube open or any other website with white background, you will notice the screen reflection is all blue. This pretty much shows you the amount of blue light that most people's eyes are trying to fight against and focus on. Most people with bad vision are ok with LED backlit displays. Usually the better the eye sight the worse it gets when you try to look at blue light halo. You can see a good comparison of LED to CCFL here: https://pcmonitors.info/articles/the-evolution-of-led-backlights/
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There is a woman at work who wears glasses that have blue light blocking lenses. Every time I see her the lenses look like blue neon signs. And that is just in open space under fluorescent lights, not in front of an W-LED backlit monitor.
 
QLEDs have less glow, but that’s not because they aren’t using WLEDs in the backlight. Someone earlier in the thread pointed out that it’s the full stack of backlight, polarizer / filter, panel and assembly that leads rto glow and IPS is more prone to it than VA. TNs have such bad off angle characteristics that glow looks different than on IPS and VA.
 
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