Uneven illumination

John

Thanks for posting your, very interesting, info.

Would the Aluminium PowerBook screen assemblies be identical to the Titanium you worked on?

My PB has the exact same problem. When I power it on, or wake it from sleep, I get the dark dome at the bottom of the screen, roughly from the center to right side. This seems to go away after three minutes, but it disturbs me nonetheless. It also seems that the left side of the screen may be slightly darker than the right. It's so slight that I'm not sure if I'm just looking for things or not. Finally, I have a little band of discolored pixels on the lower right side after everything's warmed up and the dome of doom is gone.

This is really annoying, especially since it seems iBooks don't have this problem, and I probably could have done most of what I wanted with one of them. Do problems like this occur for many laptops? I don't remember ever seeing anything like this on a PBG3 I used at a job for two years. I've also seen or used several PC laptops that didn't have any major, or even minor, LCD issues.

The fact that this defect is likely to come back after I send it in is equally disheartening. I already had to send it in to get the FW400 port working properly. My battery was also part of the recall, and the new battery refuses to charge beyond 99% no matter what I do. I have buyer's remorse, which is something I can't say about the SIX other Macs I've owned over the last twelve years. Is Apple the new lemon?

No, the Aluminum Powerbook displays would be different display models, even if their dimensions are the same (display manufacturers release new versions every year), but their basic design, as far as the backlight and its reflector are concerned, would probably be similar. Slight design changes, and/or more careful assembly, would probably have to be made to avoid a repeat of the warped reflector problem.

Many of the iBooks, at least the earlier iBook G3, have similar uneven illumination problems--I've got one on the workbench right now for other problems--so getting an iBook wouldn't necessarily have been the solution, though I don't recall whether I've seen this problem with the iBook G4. Also keep in mind that some people find that even if their iBook or Powerbook doesn't display these problems right away, the problem sometimes develops over time, so it's not really possible to tell if the newer models are immune to this problem, even if they don't have it right now. At least with your Powerbook, you're lucky enough to have one where the illumination evens out after the Powerbook has been on for a little while.

As far as your battery not charging beyond 99%: your battery's 99% might be better than other people's 100%, in terms of how long it allows your Powerbook to run. If it runs for at least an hour and a half, or two hours, from this battery, without your having to dim the screen, run in reduced speed mode, etc., that's about average.

I know after spending some big bucks, we'd want these products to work without flaws like these, but unless the problem is a real deal-breaker, sometimes that's the luck of the draw. But that doesn't mean we shouldn't keep asking Apple to be more consistent in their quality control.

OMIGOODNESS! I thought I was losing my mind when I started seeing the bottom left quadrant of the screen appearing darker than the rest. I also have three white spots that, together, form a triangle in the center area of the screen.

This is very annoying. I do have a 17" PB, so don't know if that makes a difference (I just noticed I'm in the 15" section of the board).

I guess I'm going to have to take it in...

Hi Phil:

I was thinking about what you had said about getting my PB repaired and wanted to update you.

This month (September) my hard drive failed and I finally relented and took the Powerbook to the Apple Store in the Houston Galleria. I showed the Apple Genius my dead hard drive, my white-spotted screen and mentioned that my keyboard had been sticking a little bit. He wrote up the repair and sent it in. 72 hours later it was back with a new screen, a new hard drive, a new liner for the keyboard, and a fresh install of 10.4.2. All these repairs were covered under my Apple Care Warranty.

It's just like having a new Powerbook and everything works great.

I was deterred from sending it in primarily by all the negative experiences reported in these forums. But the old adage really is true: People with bad experiences are much more likely to post that those with positive experiences. Just a sad fact of human nature I guess.

I thought you might be amused by my procrastination. 🙂

Cheers:

Marby

I have replaced every part on my ALpowerbook 15" expcet the cpu and bottom case.

I am about to go for my third display because of uneven illumination.

I was wondering since I have had more then three majour parts replaced, Is it apples responsability to give me a new powerbook?

Whilst it's not specifically Apple's responsibility to give you a new PowerBook, you might be able to negotiate a replacement.

Have these repairs occured within a 12 month time frame? If so, and you have already had three major repairs, then you can try to negotiate for a replacement.

I have had my PowerBook for just over a year, and I recently noticed the uneven illumination that Phil and beekicker describe. I have a dark patch, like a dome, at about the bottom centre of the screen, extending about 1/4 to 1/3 of the way up the screen. I tend to notice it out of the corner of my eye (where we're most sensitive to differences in brightness), and it's very distracting, for instance when I'm reading text. It's noticeable only with plain, light backgrounds, not photos or videos. I wondered if what causes it is heat. You may have noticed that if one of the fans, probably the left-hand one, turns on, it vents onto the screen (why Apple did it like that, I don't know). After several seconds, the screen will darken where the hot air hits it. Now, if I touch the lower screen bezel and hinge, it is invariably very hot - much hotter than the strip above the keyboard is most of the time. And the hottest spot is just slightly to the right of the word 'PowerBook' just below where the dark shadow starts. There must be something in addition to the display cabling in the hinge housing to generate this heat - the inverter board? - I don't know. But should it be getting this hot? However, Jerry's very useful photo seems to suggest that the 'dome' problem is a milder (or earlier!) form of the dark bottom-right quarter of the screen issue, so this is unlikely to be caused by heat.

The thing that gets the hottest in the display, is the lamp, a long thin fluorescent tube which runs the bottom length of the display, behind the bottom bezel. I haven't taken the time to touch the inverter board to see how hot it gets, but the lamp gets plenty hot. There's nothing in the display hinge besides cabling--the hinge get hot because the lamp just above it gets hot, and and because the processor and hard drive get hot, and some of this heat transfers to the hinge by way of the heat sink, which runs the length of the inside rear of the Powerbook, and some heat is transferred by the fan, as it exhausts hot air onto the lower part of the display.

Uneven illumination can begin right away with some Powerbooks, as soon as you power it up, and can take a little while with other Powerbooks. In an earlier post, I described what I believe is the main cause of uneven illumination--the lamp's reflector not being perfectly aligned with the bottom of the display. It may be slightly warped. Heat generated by the various sources I describe above, can warp the reflector further, or unwarp it, as the Powerbook is running, causing the unevenly illuminated areas to change.

I am ready to join the club. I bought a 12inch PB in june, and this week I started to see the dark spot in my lower right corner. Its pretty bad coming back from screensaver, and it eases off a little bit with time, but is still apparent. How can Apple do nothing if there is so many of us with the same problem? Anybody dealt with the problem in Montreal?

Exact same story here John. I bought my PB 12in in June '05, and just last week noticed the dark area, but in the center bottom of my screen. It is the worst when coming back from the screensaver. I am especially upset at the fact that this is my first apple notebook, after years of pc notebooks, without one single hardware issue. I guess I was just lucky. I would certainly hope that Apple would address this "common" issue and step in to defend the exceptional quality of their products. Can anyone post any positive word about this problem being 100% resolved?

Hi John ( - Sawyer),

I read your long (& superb) post above with interest a few weeks ago having developed the intermittent 'dark patch' problem in the lower right side of my 15" aluminium Powerbook's display. Your theory on the deflector getting distorted over time certainly made sense, & so - based on your advice AND previous not-so-great experiences of having my old titanium Powerbook repaired - I decided I'd live with the 'problem' as it isn't too bad once the PB's been on for a while...

However, I wanted to provide some additional feedback here because - whilst you may be right to some extent about the deflector distorting - I honestly think there may be something else (electrical) going on, be it with the LCD, backlight or inverter board (etc etc) :

I've noticed that when I power-up the PB (when it's cold first thing), the display illumination's pretty good... BUT, whilst the screen's still displaying the grey boot-up background with the 'radar' icon spinning, the dark patch appears (& pretty badly too) in approx' 5 > 10 seconds, all before arriving at the blue background with the login window, & long before heat could possibly enter the equation.

So... could this be an inverter board or RF (or something else) problem as you earlier thought? I never thought tubes could produce less light in one area than the rest, but it certainly looks like it from where I'm sitting, based on how quickly the 'fault' changes...

Thanks!

Jason

I've had the uneven illumination as well, twice! (two replacement diplays...)
I've also had the white spots problem, this problem twice as well... (two more replacement displays...)
Then ive also had problems with dead pixels on one display, 24! dead pixels... (another replacement display...)
Then my dear powerbook started to freeze, time for a logic board replacement...
So finally my powerbook powersupply started sounding really high and we added a powersupply card to the replacement list...

So after all, 5 displays, 1 logicboard and 1 powersupply card. My impression of that Apple's products are fine quality is gone, but finally i've got myself a working (non-freezing) powerbook with a perfect display (no defects at all)...

Still think that my powerbook is awseome, looks so nice, os x is so sweet and it's so quiet. The apple service personel at the local apple reseller has been really helpful aswell during all the repairs. Love my macintosh but feel kind of ripped of when all my friends cheap 1000$ laptops work fine and show no sign of display problems...