Dell U2312HM--Manufacturing defect or not? Need advice

user99

n00b
Joined
Jun 5, 2012
Messages
6
Hi everyone. I just received my U2312HM in the mail and I'm wondering if a silvery-blue "sheen" or "tint" in the bottom-right corner of my display is a manufacturing defect or just an unfortunate characteristic of these particular displays. Below are four pictures of what I'm seeing. It's noticeable on darker images, even when sitting right in front of the monitor (not off-axis). I apologize for the pictures--they seem a little over-exposed (I don't own a good camera) and exaggerate the problem, making it seem a little more noticeable as it actually is. The sheen (or tint?) is much less noticeable when I'm more than a few feet away from the monitor, and when I line my eyes up directly with the corner. The display also seems to have a very slight silvery-red sheen on bottom-left corner, but it's almost impossible to notice compared to the tint of the bottom-right corner (which is always visible, looking for it or not). Basically, it's hard to see dark details in the bottom-right because of the tint.

I haven't RMA'd the monitor yet because I haven't ever owned an IPS display (just "upgraded" from two Dell P1130's) and I've found a bunch of posts by people who seem to have a very similar issue in exactly the same spot. Basically, I'd like someone who owns a U2312HM and is familiar with the tech to let me know if they think I should RMA the monitor or not. Apart from this issue, it seems like a great monitor for the price, so if this isn't an actual manufacturing defect, I won't sweat it. Any advice is appreciated.

Here's my monitor:
http://imgur.com/a/pM2VF#3
More pics

Here are people with a similar problem:
http://hardforum.com/showpost.php?p=1037116790&postcount=1548
http://hardforum.com/showpost.php?p=1037112306&postcount=1535
http://forums.overclockers.co.uk/showpost.php?p=20156197&postcount=201
http://forum.lowyat.net/topic/2014372/+1820 (requires scrolling)
http://www.sweclockers.com/forum/10...00-kr-e-ips-eller-tn/index2.html#post12082623

Thanks
 
Last edited:

cvgd

Limp Gawd
Joined
Mar 20, 2011
Messages
421
This is called "backlight bleed". Some is inevitable with any monitor, and it tends to be worse with LED backlights, as there are inefficiencies in the diffuser/reflector, which can increase variance in panel luminosity.

Your situation looks pretty bad, outside what I would consider acceptable. I would return it. Back light bleed varies from monitor to monitor within the same model line, and your next one is likely to have less bleed.
 

user99

n00b
Joined
Jun 5, 2012
Messages
6
This is called "backlight bleed". Some is inevitable with any monitor, and it tends to be worse with LED backlights, as there are inefficiencies in the diffuser/reflector, which can increase variance in panel luminosity.

Your situation looks pretty bad, outside what I would consider acceptable. I would return it. Back light bleed varies from monitor to monitor within the same model line, and your next one is likely to have less bleed.

That's a shame... thanks for the heads-up. Could it be anything else, other than backlight bleed? I ask because I've owned a few tablets which had backlight bleed and it looked a bit different than this. This reminds me of the IPS "glow" that you see when viewing dark colors from extreme angles. Also, someone else (from here, I think) mentioned that their replacement monitor had the same issue. If it's something other than backlight bleed, it'd be a bummer to RMA it and get another one with the same thing.
 

Namelessme

[H]ard|Gawd
Joined
Jan 3, 2012
Messages
1,161
It looks like bleed to me too. Not that I'm an expert or anything, but based off of pics others have posted, it looks bleedy to me.

For IPS glow, I think it's a bit more uniform, usually in the corners and changes based on your viewing position -- others correct me if I'm wrong. The Dell 2412 I had sort of had a white glow in the corners, which spread out some. But I don't think it looked like your pic.

If it was me, I'd RMA it, and verify that if the replacement is worse, you can simply return and get a complete refund. But I'm sort of picky about bleed. Unless you can just live with it as it is now... in which case, just keep it.
 

cvgd

Limp Gawd
Joined
Mar 20, 2011
Messages
421
If it were IPS glow, it would shift based on your viewing angle. When you are directly perpendicular to an area of the screen, glow effect should disappear.

IPS glow derives from how the IPS pixel matrix blocks out the backlight. It's very effective from head on, but from acute angles, there is some leakage, which results in contrast reduction/elevation of black levels.

Backlight bleed does not shift based on perspective, though there can be an additive effect with glow, such as that you see additional lightening at acute angles. If you have your face in the corner and are staring directly at the relevant area, and it remains significantly brighter, you've got bleed.

There are multiple theories that attempt to explain bleed. The diffuser could be misaligned. The underlying leds could have different brightness. There could be pressure from the bezel (perhaps causing diffuser misalignment). It just happens sometimes. I have no idea how often, or what percentage of IPS monitors suffer from it, or even how it varies among manufacturers.
 

user99

n00b
Joined
Jun 5, 2012
Messages
6
Thanks everyone. In the OP I mentioned,
The sheen (or tint?) is much less noticeable when I'm more than a few feet away from the monitor, and when I line my eyes up directly with the corner.
I meant that when viewing with my eyes aligned to about the center of the screen, the silver tint muddies dark details in that corner. But when I move my head to that corner, or move a few feet away from the display, it seems less significant. It also doesn't look like the light bleed that I'm familiar with. However, it's clearly much brighter in that spot according to what my camera picks up, and I don't think it's "normal" even when looking at it directly. So I'm still unsure. Could it be IPS glow because it shifts? I'm mainly going back and forth because I don't want to ship it out only to receive a different display with the same "problem"--I've had bad experiences with that recently and it was a headache.

Here are some pics which demonstrate what I mean (click to expand):


Normal viewing position:



Close up on the corner:



Further back:


Additional pics:
http://imgur.com/a/Vxnm0#3
Picture 3, 4, and 6 are from "normal" viewing positions. Notice how when I back up a bit or move the camera to that corner, the effect is much less noticeable, It shows up differently on camera than it actually looks, but that's still a pretty good representation of what's happening. Could this be a combo of excessive light bleed and the IPS glow effect?
 
Last edited:

cvgd

Limp Gawd
Joined
Mar 20, 2011
Messages
421
Yeah, it looks like pretty bad backlight bleed exacerbated by IPS glow.

You seem resistant to going through the RMA process. Are you just wary of the hassle given that your next monitor might not be a significant improvement? It probably will be significantly better, but you're correct that it may not be.
 

user99

n00b
Joined
Jun 5, 2012
Messages
6
Yeah, it looks like pretty bad backlight bleed exacerbated by IPS glow.

You seem resistant to going through the RMA process. Are you just wary of the hassle given that your next monitor might not be a significant improvement? It probably will be significantly better, but you're correct that it may not be.

Well, I've been having trouble with a lot of my recent tech purchases. (Is nothing made well now? I don't get it.) My laptop has actually been in limbo for a total of probably two or three months as a result of RMA process shenanigans. It's probably been sent back and forth six or seven times in total... Not to mention the fact that I had to go through five or so tablets before finding one without major manufacturing defects, one which was actually worth its price. Nothing too serious, but I've just had a bad luck streak and I don't want to unnecessarily inconvenience myself further. But since the verdict seems pretty unanimous, and because the color distortion is starting to bug me, it's definitely going back to Dell this week.

Appreciate the advice guys. :)
 

DirtyB

Gawd
Joined
Jun 30, 2007
Messages
830
I have the 2311 and mine looks very similar. I can't really complain tho considering the price I paid for it.
 

DirtyB

Gawd
Joined
Jun 30, 2007
Messages
830
Yeah I have backlight bleed in the bottom two corners. Doesn't really bother me except on all black screens.
 

tk-don

Limp Gawd
Joined
Jun 15, 2010
Messages
324
Judging from your last three images, it's a little bit of backlight bleed, while most of it is "glow".
An LCD panel basically consists of a backlight, two sheets of polarizers (back + front) and the LCD matrix sandwiched between the polarizers. The angle that the two polarizers are rotated compared to each other corresponds to the how much the liquid crystals can twist. The angle of the back polarizer corresponds to block all light, when the crystals are "resting" (for IPS or VA).
If these two polarizers aren't perfect with regards to polarization or perpendicular to one another, the amount of polarization becomes offset, meaning the backlight will look non-uniform.

White glow can be caused by the fact that the liquid crystal may not perfectly shift in-plane, meaning that the amount of polarization wouldn't look the same from all angles.

TL;DR: I would try going for an exchange, as the amount of white glow can change slightly from panel to panel.
 

Crake8

Limp Gawd
Joined
Jun 6, 2012
Messages
129
I had a U2312HM for a week and I do not recall it having a glow like that, so perhaps yours is defective.
 

Racer_J

Gawd
Joined
Jan 17, 2012
Messages
657
I'm going to agree with tk-don. It looks like a combination of flashlighting (when the backlight bleeds out in the corner and illuminates an area like a flashlight does) and IPS glow. Flashlighting and backlight bleed along the edges is fairly common on edge light LED displays. You can do an exchange to try and get a better one but, you can actually end up with something far worse.
 

user99

n00b
Joined
Jun 5, 2012
Messages
6
I'm going to agree with tk-don. It looks like a combination of flashlighting (when the backlight bleeds out in the corner and illuminates an area like a flashlight does) and IPS glow. Flashlighting and backlight bleed along the edges is fairly common on edge light LED displays. You can do an exchange to try and get a better one but, you can actually end up with something far worse.

Thanks, and thanks to everyone above as well. After using it for a couple of days, the bleed or whatever it is is pretty extreme in that corner, to the point that it bugs me. So I'm going to take a shot at getting a better one. I hear Dell's customer service is pretty helpful, so hopefully that's true.
 
Top