X220 IPS display backlight issue (with photos)

Question

Hello,
I've purchased the Lenovo X220 laptop with the Premium HD IPS display and I do have a problem with it (see below).
Laptop was purchased something like month ago and I've spotted this after I've started to work with it more heavily but after 14 days, so I was not able to return it to the seller (http://www.lenovoonline.cz).
When you put backlight to maximum you see that the display is not evenly lighted and forming bright spots on the bottom of it. It's most noticable on the black background.
I've sent notebook for repair (http://www.pcnet.cz) with this description (translated to english):
"With maximum brightness set and the black display/background (eg. BOOT screen) on the bottom edge of the display there are visible white spots/maps. Small but visible and not even with different sizes. It's most visible on black background and while limiting external light (darker room, working in the night). Spots highlights even more when you try to pull the display towards you into steeper angle."
The laptop has been in the repair for 2 weeks and the result was this description:
"This kind of display is very sensitive to any pressure, and it will result in the brightening the place. It is specific for this model line and it's not the reason to warranty repair. We recommend to lower the brightness level in the darker room. Check of the display frame has been done and no problem has been found."
Later they said they've replaced the panel too.
However the issue still persists (see attached photos).
Let me say few words about this:
display is showing the spots while in rest I'm not touching it, if it's sensitive for pressure than it is indicating that there's some pressure on it while mounted in the frame
I want to have backlight lighting the display evenly on the whole surface area, that's the correct function of a product anything else is NOT
if they claim this is how it should be and it's actually a "feature" of the PREMIUM display then if I had known I would choose regular TN display and even save some money, needless to say that in that case the word PREMIUM sounds like a bad joke
after lowering brightness level problem doesn't go away, still visible just gradually slightly less, depending on the brightness set
if you are working in the night without external light this is VERY irritating
So my question to you X220 community is, do you happen to have same issue?
as they say it's "normal" with X220
Thanks
EDIT1:
I've done a search now and it seems I'm not alone with this issue
PS:
I'm attaching two photos.
First is the X220 (booted into GNU/Linux with X running and mouse as reference).
Second is the very old Z60m (booted into Windows and running blank screensaver).
Compare for yourself which one you would prefer.
It was shooted in absolute dark (I'm used to work like that) with Canon EOS350D on tripod.
There are some slight artifacts which you normally not percieve but anyway I think it clearly shows my point.
X220
Link to image 1
Z60m
Link to image 2
Moderator note: images larger than 50k converted to links per forum rules: Lenovo Community Participation Rules

Answer 1

Yes, at maximum brightness level the backlight bleeding is very visible but I use it at 5 or 6 level where it has excellent contrast ratio considering how crappy current notebook displays are in general. The uneven backlight is caused by fancy LED backlight which is still not able to deliver similar quality regarding uniformity as good old CCFL backlight (that's why professional LCD monitors still rely on W-CCFL backlight). But I agree that the top-left corner is way too much bad and might indicate that the panel is seated badly in the frame. On the other hand my old IPS panel in R51 also have backlight bleed at maximum brightness level.
Major problem is that Lenovo is still not able to fix the stupid bug with brightness level always set to max in BIOS screen that the backlight bleeding is very visible and irritating everytime you boot your machine.
IMHO, the X220 IPS panel is still much better than any ugly contrastless TN panel Lenovo puts into ThinkPads (except 15" FHD). I bet that you would hate the X220i TN panel more than this one
There are also two different revisions of the IPS panel, the second one fixes problems with image retention. As for comparison with Z60m, X220 display lid is much more fragile so the panel is not protected well against pressures and flexes. In any case panel flex should affect the backlight bleeding temporarily only. If it persists it is subject to repair (replace, reseat etc.).
Unfortunately I don't have any good low-light camera that takes useable pictures in dark environment so I can't post relevant images of the backlight bleeding.