a31 2653 lcd brightness during daylight

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housedl · #1 Post by **housedl** » Sat Feb 16, 2008 2:05 pm

my lcd is not very bright during the daytime. i guess a better description would be that it looks good at night but it just doesnt seem to get bright enough for the daytime... it is difficult to see a dvd and most dvd software doesnt allow a 'brightness' option and the ones that do just make it look white.. i have the brightness turned all the way up with the function home/end keys...

any fixes for this.. or is this just an indicator of lcd going out.. i had it replaced once already..

thanks
darrell

i have all the latest drivers running windows xp...

housedl · #2 Post by **housedl** » Sat Feb 16, 2008 2:27 pm

i just found this thread... would letting this user replace whatever he replaces make my screen brighter??

http://forum.thinkpads.com/viewtopic.ph ... 0cb5d0b771

sjthinkpader · #3 Post by **sjthinkpader** » Sat Feb 16, 2008 4:15 pm

I've replaced a few CCFs but only used tubes from cracked panels. The user jamiphar may have a stock of new CCFs. If you have all the symptoms of CCF going out, it may be best to send the panel off to him.

ajkula66 · #4 Post by **ajkula66** » Sun Feb 17, 2008 1:02 am

I've sent you the pictures you requested, and you will see that James' work compares very favourably to factory backlights...

What's the full 7-character code of your machine?

housedl · #5 Post by **housedl** » Sun Feb 17, 2008 4:56 am

ajkula66 wrote:I've sent you the pictures you requested, and you will see that James' work compares very favourably to factory backlights...

What's the full 7-character code of your machine?

Computer Model: 2653H5U

ajkula66 · #6 Post by **ajkula66** » Sun Feb 17, 2008 10:48 am

OK, so you have one of the early A31p machines...two things here:

a) FlexView IPS screens seem dimmer than "normal" LCDs even when brand new.
b) Your machine is five years old. If you still have the original LCD, it is likely at the end of its natural life. Replacing the CCFL will make a world of difference.

pianowizard · #7 Post by **pianowizard** » Sun Feb 17, 2008 11:26 am

Few Thinkpads, including brand new ones, are bright enough to be used under direct sunlight or in a brightly lit room. My office gets lots of sunlight and during the day I usually need to close all curtains and turn off the room light in order to see the screens on my R50p and T42.

Do you remember whether this A31p has always seemed too dim during the day, or did this problem start only recently? If you've had this problem since day one, then I don't think anything is failing.

ajkula66 · #8 Post by **ajkula66** » Sun Feb 17, 2008 12:26 pm

I'm sure that my friend pianowizard will agree that any 5-year old LCD will be dimmer than the new one, even if it hasn't been used a lot...

A new backlight is the solution to this problem. I've recently had an A31p that came back from IBM under warranty repair with a brand new LCD, and the one where James had replaced the backlight was still brighter by quite a margin.

That being said, any imperfections that exist on the LCD (scratches, dirt, dead pixels) will also be much more noticeable with a new backlight.

pianowizard · #9 Post by **pianowizard** » Sun Feb 17, 2008 12:32 pm

ajkula66 wrote:I'm sure that my friend pianowizard will agree that any 5-year old LCD will be dimmer than the new one

Yep, I agree with you, as usual. But we don't know whether the OP's A31p is only slightly dimmer or much dimmer than when it was new, so I asked him those questions to help determine whether it's worth shelling out $150 to replace the backlight. If such replacement makes the screen only a little bit brighter, then it may not be worthwhile.

sjthinkpader · #10 Post by **sjthinkpader** » Mon Mar 31, 2008 4:43 pm

I found my old Topcon luminance meter (BM-8) and measured a few LCDs in the house last night and here are the results:

Backgound: a blank web page.
The meter about an inch from the LCD

T42 15 inch SXGA+ IPS, ~195 NITs (spec 200 NIT)
A30p 15 inch UXGA IPS, ~115 NITs (spec 200 NIT)
T41 14.1 inch SXGA+, ~75 NITs (spec 150 NIT)

The T42's display was just replaced by Lenovo so it is close to the spec at 200 NIT. The A30p LCD is from 2002 and now close to half the original brightness of 200 NIT. The T41 SXGA+ was from 2004 and also close to 50% of the original 150 NIT. The brightest spot is in the middle close to the bottom. The upper edge is less bright.

So yes, they lose quite a bit of brightness over time.

beeblebrox · #11 Post by **beeblebrox** » Mon Apr 28, 2008 10:03 am

sjthinkpader wrote:I found my old Topcon luminance meter (BM-8) and measured a few LCDs in the house last night and here are the results:

Backgound: a blank web page.
The meter about an inch from the LCD

T42 15 inch SXGA+ IPS, ~195 NITs (spec 200 NIT)
A30p 15 inch UXGA IPS, ~115 NITs (spec 200 NIT)
T41 14.1 inch SXGA+, ~75 NITs (spec 150 NIT)

The T42's display was just replaced by Lenovo so it is close to the spec at 200 NIT. The A30p LCD is from 2002 and now close to half the original brightness of 200 NIT. The T41 SXGA+ was from 2004 and also close to 50% of the original 150 NIT. The brightest spot is in the middle close to the bottom. The upper edge is less bright.

So yes, they lose quite a bit of brightness over time.

Unfortunately, LCDs with a CCFL die after a few years. There is nothing, absolutely nothing you can do. Trust me, I have replaced a few CCFLs myself in various Thinkpads.

The CCFL simply destroys the LCD with its harsh UV light. The older the CCFL the hotter both ends of the lamp will grow and more UV light goes thru the panel.

Well, the CCFL either might go supernova, it either burns thru that's when the inverters switch off the current due to overload, or it turns in to a red sun when mercury is depleted and only Neon is ionized.
Or the lamp just fades away, when all gas is either depleted (on old lamp designs) or mercury is lost thru spattering.

In all cases the LCD will suffer tremendously by UV light, it darkens and turns yellowish. If you change the backlight after a couple years of heavy use, you have a brighter but yellowish LCD.
You will get about 60% of the original brightness, not more.
Interested folks might wanna google for "Sanken Electric & CCFL", there is a lot of excellent info.

That's why I am looking forward to LED backgrounds. This should eliminate the UV problem

a31 2653 lcd brightness during daylight

a31 2653 lcd brightness during daylight

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