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Laptop Screen Problem

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  Laptop Screen Problem Enrie Membership <me2@privacy.net> - 2012-11-14 09:12 +0000
    Re: Laptop Screen Problem wrat@panix.com (the wharf rat) - 2012-11-14 22:29 +0000
      Re: Laptop Screen Problem Bob_Villa <pheeh.zero@gmail.com> - 2012-11-16 04:15 -0800
        Re: Laptop Screen Problem wrat@panix.com (the wharf rat) - 2012-11-16 18:39 +0000
          Re: Laptop Screen Problem mike <ham789@netzero.net> - 2012-11-16 13:52 -0800
            Re: Laptop Screen Problem wrat@panix.com (the wharf rat) - 2012-11-17 01:14 +0000
              Re: Laptop Screen Problem mike <ham789@netzero.net> - 2012-11-16 20:20 -0800
                Re: Laptop Screen Problem Bob_Villa <pheeh.zero@gmail.com> - 2012-11-17 07:08 -0800
                Re: Laptop Screen Problem wrat@panix.com (the wharf rat) - 2012-11-17 17:44 +0000
                  Re: Laptop Screen Problem mike <ham789@netzero.net> - 2012-11-17 18:04 -0800
                    Re: Laptop Screen Problem Michael Black <et472@ncf.ca> - 2012-11-17 22:30 -0500
                      Cute magnet story (was: lcd blah blah blah) wrat@panix.com (the wharf rat) - 2012-11-18 18:46 +0000
                        Re: Cute magnet story mike <ham789@netzero.net> - 2012-11-18 13:14 -0800
                          Re: Cute magnet story wrat@panix.com (the wharf rat) - 2012-11-19 06:30 +0000
                            Re: Cute magnet story ak621@chebucto.ns.ca (Richard Bonner) - 2012-11-24 22:44 +0000
                          Re: Cute magnet story ak621@chebucto.ns.ca (Richard Bonner) - 2012-11-24 22:38 +0000
                    Re: Laptop Screen Problem wrat@panix.com (the wharf rat) - 2012-11-18 18:24 +0000
          Re: Laptop Screen Problem Bob_Villa <pheeh.zero@gmail.com> - 2012-11-18 16:10 -0800
            Re: Laptop Screen Problem wrat@panix.com (the wharf rat) - 2012-11-19 06:39 +0000

#1663 — Laptop Screen Problem

I have a Samsung laptop with a screen problem.

http://imageshack.us/a/img838/206/screenproblem.jpg

This is an LED back-lit 15.6" screen. I thought the screen was faulty as 
I get a normal display when I connect the laptop to an external monitor 
so I purchased a new screen but the new one exhibits the same fault. I 
have also replaced the ribbon cable that connects the screen to the 
motherboard.

Both the original screen and the new one show the same pattern and are 
not cracked or damaged.

Screen resolution is set to correct value so is colour depth

Has anyone seen anything like this?

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#1664

In article <k7vn9l$dia$1@speranza.aioe.org>,
Enrie Membership  <me2@privacy.net> wrote:
>I have a Samsung laptop with a screen problem.
>
>
>Has anyone seen anything like this?


	You're *sure* the second screen was good?  You're *sure* you 
reassembled it using the new screen?  (You won't be the first guy who put
the old bad parts back in by mistake.)

	Is there an auto adjust feature somewhere in the driver menus?

	That looks to me like an LCD being driven far off its native
resolution, or one with a honking big magnet somewhere very close.

	Maybe you got the wrong part?  Some laptops are sold with
several different screen resolutions.

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#1665

On Wednesday, November 14, 2012 4:29:49 PM UTC-6, the wharf rat wrote:
...or one with a honking big magnet somewhere very close.

I never heard this so I tried a large magnet on my LCD...no distortion.  

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#1666

In article <5932ee0e-a606-4bd7-b61c-be3b2d4e251a@googlegroups.com>,
Bob_Villa  <pheeh.zero@gmail.com> wrote:
>
>I never heard this so I tried a large magnet on my LCD...no distortion.  
>

	Try a bigger magnet.  But be ready to by a new lcd.

	The "liquid crystals" are affected by magnetic fields.  The LCDs
on certain medical equipment like MRIs have to be replaced periodically 
because they start to bleed green and purple lines.

	Think about it.  They use magnetic fields to align the crystals to
pass light.  You just need a strong enough magnet.

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#1667

On 11/16/2012 10:39 AM, the wharf rat wrote:
> In article<5932ee0e-a606-4bd7-b61c-be3b2d4e251a@googlegroups.com>,
> Bob_Villa<pheeh.zero@gmail.com>  wrote:
>>
>> I never heard this so I tried a large magnet on my LCD...no distortion.
>>
>
> 	Try a bigger magnet.  But be ready to by a new lcd.
>
> 	The "liquid crystals" are affected by magnetic fields.  The LCDs
> on certain medical equipment like MRIs have to be replaced periodically
> because they start to bleed green and purple lines.

Given a strong enough magnetic field, you could probably create a worm hole.
But for magnetic fields we can create here on Earth, not so much.
I don't doubt that stuff in the vacinity of a MRI can be affected.
>
> 	Think about it.  They use magnetic fields to align the crystals to
> pass light.  You just need a strong enough magnet.

I'd like to see the citation on that assertion.
>

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#1668

In article <k86cjf$m50$1@dont-email.me>, mike  <ham789@netzero.net> wrote:
>>
>> 	Think about it.  They use magnetic fields to align the crystals to
>> pass light.  You just need a strong enough magnet.
>
>I'd like to see the citation on that assertion.
>>
>

	Well, how do *you* think they align the things?  They're polarized,
you put current near one end and they all line up (ok, "untwist", whatever,
they're still driven by magnetic force, or else LCD's would require quantum
mechanics).  

	Heck, even if the crystals somehow aren't sensitive to magnetism
there's a whole array of little teeny transistors behind them that certainly
are.  Try taking the back off the display and laying your magnet right on the
actual LCD unit.  That might show something.  In fact, if I can find a nice big
magnet I'll try it on a broken one this weekend.  Probably electrocute myself.

	And what about the backlight?  Bet that doesn't like big magnets...

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#1669

On 11/16/2012 5:14 PM, the wharf rat wrote:
> In article<k86cjf$m50$1@dont-email.me>, mike<ham789@netzero.net>  wrote:
>>>
>>> 	Think about it.  They use magnetic fields to align the crystals to
>>> pass light.  You just need a strong enough magnet.
>>
>> I'd like to see the citation on that assertion.
>>>
>>
>
> 	Well, how do *you* think they align the things?  They're polarized,
> you put current near one end and they all line up (ok, "untwist", whatever,
> they're still driven by magnetic force, or else LCD's would require quantum
> mechanics).

Think you need to do some research on how LCD's work.  They're electric 
field devices.  Yes, there is a relationship between electricity and
magnetism, but that ain't what's in play here.

Given your description your position, I suggest you
refrain from implying that you understand quantum mechanics.
>
> 	Heck, even if the crystals somehow aren't sensitive to magnetism
> there's a whole array of little teeny transistors behind them that certainly
> are.  Try taking the back off the display and laying your magnet right on the
> actual LCD unit.  That might show something.  In fact, if I can find a nice big
> magnet I'll try it on a broken one this weekend.  Probably electrocute myself.
>
> 	And what about the backlight?  Bet that doesn't like big magnets...
Yep, given enough magnetism, you can probably make the universe
implode.  That ain't in play here either.

Let me add that the CRT display IS significantly affected by magnetic 
fields.

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#1670

On Friday, November 16, 2012 10:20:14 PM UTC-6, mike wrote:


> 
> Let me add that the CRT display IS significantly affected by magnetic 
> 
> fields.

Now you're adding insult to injury...how rude!

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#1671

In article <k8739t$db9$1@dont-email.me>, mike  <ham789@netzero.net> wrote:
>On 11/16/2012 5:14 PM, the wharf rat wrote:
>
>Think you need to do some research on how LCD's work.  They're electric 
>field devices.  Yes, there is a relationship between electricity and
>magnetism, but that ain't what's in play here.
>

	If there's a moving electric field, there's magnetism.  

	If "liquid crystals" weren't sensitive to magnetic fields then 
LCDs might not exist.  Vsevlood Freedricksz is credited with discovering 
the behavior; he discovered the Freedricksz transition by applying magnetic 
fields to films of liquid crystals.  

	I'd rather you explained my error than just make snide remarks
about how little I must know.  This is supposed to be a learning experience.

	When you put voltage into them, the dipoles line up, right? When
dipoles align you get paramagentism, no?  Liquid crystals are para-magnetic
as shown by Freedricksz...  Exposing an LCD to a sufficiently strong
magnetic field WILL cause the crystals to migrate. Magnetic fields alter
the flow of electrical charges.  What happens to the transistors in an LCD
when you expose them to a strong magnet while they're turned on?

	If you can explain why an LCD wouldn't be effected by a strong
magnetic field given this I'm sure I'm not the only one who'd appreciate it.

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#1672

On 11/17/2012 9:44 AM, the wharf rat wrote:
> In article<k8739t$db9$1@dont-email.me>, mike<ham789@netzero.net>  wrote:
>> On 11/16/2012 5:14 PM, the wharf rat wrote:
>>
>> Think you need to do some research on how LCD's work.  They're electric
>> field devices.  Yes, there is a relationship between electricity and
>> magnetism, but that ain't what's in play here.
>>
>
> 	If there's a moving electric field, there's magnetism.
>
> 	If "liquid crystals" weren't sensitive to magnetic fields then
> LCDs might not exist.  Vsevlood Freedricksz is credited with discovering
> the behavior; he discovered the Freedricksz transition by applying magnetic
> fields to films of liquid crystals.
>
> 	I'd rather you explained my error than just make snide remarks
> about how little I must know.  This is supposed to be a learning experience.
>
> 	When you put voltage into them, the dipoles line up, right? When
> dipoles align you get paramagentism, no?  Liquid crystals are para-magnetic
> as shown by Freedricksz...  Exposing an LCD to a sufficiently strong
> magnetic field WILL cause the crystals to migrate. Magnetic fields alter
> the flow of electrical charges.  What happens to the transistors in an LCD
> when you expose them to a strong magnet while they're turned on?
>
> 	If you can explain why an LCD wouldn't be effected by a strong
> magnetic field given this I'm sure I'm not the only one who'd appreciate it.

My sincerest apologies.  You are correct.  You cannot have a dynamic 
electric
field without creating a magnetic field somewhere in the universe.
And if that field is STRONG, anything can happen.

I'm confident that you and Mr. Maxwell can come up with equations describing
how LCD's work in magnetic terms.

I, however, will continue to use the simpler electric field model.
I'm just stubborn that way.

FWIW, here's an experiment I just ran.
Take the strongest magnet you can find.  I used one from a hard drive.
It's not the strongest magnetic field you can generate, but it did take
a pry-bar to get it off the refrigerator.
Set it on the display of your smart phone.
Report your results.
I saw no, zero, none, not any change in the display.
How about you?
>

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#1673

On Sat, 17 Nov 2012, mike wrote:

> On 11/17/2012 9:44 AM, the wharf rat wrote:
>> In article<k8739t$db9$1@dont-email.me>, mike<ham789@netzero.net>  wrote:
>>> On 11/16/2012 5:14 PM, the wharf rat wrote:
>>> 
>>> Think you need to do some research on how LCD's work.  They're electric
>>> field devices.  Yes, there is a relationship between electricity and
>>> magnetism, but that ain't what's in play here.
>>> 
>>
>> 	If there's a moving electric field, there's magnetism.
>>
>> 	If "liquid crystals" weren't sensitive to magnetic fields then
>> LCDs might not exist.  Vsevlood Freedricksz is credited with discovering
>> the behavior; he discovered the Freedricksz transition by applying magnetic
>> fields to films of liquid crystals.
>>
>> 	I'd rather you explained my error than just make snide remarks
>> about how little I must know.  This is supposed to be a learning 
>> experience.
>>
>> 	When you put voltage into them, the dipoles line up, right? When
>> dipoles align you get paramagentism, no?  Liquid crystals are para-magnetic
>> as shown by Freedricksz...  Exposing an LCD to a sufficiently strong
>> magnetic field WILL cause the crystals to migrate. Magnetic fields alter
>> the flow of electrical charges.  What happens to the transistors in an LCD
>> when you expose them to a strong magnet while they're turned on?
>>
>> 	If you can explain why an LCD wouldn't be effected by a strong
>> magnetic field given this I'm sure I'm not the only one who'd appreciate 
>> it.
>
> My sincerest apologies.  You are correct.  You cannot have a dynamic electric
> field without creating a magnetic field somewhere in the universe.
> And if that field is STRONG, anything can happen.
>
> I'm confident that you and Mr. Maxwell can come up with equations describing
> how LCD's work in magnetic terms.
>
> I, however, will continue to use the simpler electric field model.
> I'm just stubborn that way.
>
> FWIW, here's an experiment I just ran.
> Take the strongest magnet you can find.  I used one from a hard drive.
> It's not the strongest magnetic field you can generate, but it did take
> a pry-bar to get it off the refrigerator.
> Set it on the display of your smart phone.
> Report your results.

You should have waited to publish the results.

I once did that with a Commodore monitor, and then panicked when the 
blotching didn't go away immediately.  I feared the magnet was too strong.
But it was just a matter of leaving the tv set off long enough so the 
degaussing coil would come into play when I turned it on.

I know I wouldn't have that fear with a big magnet and an LCD monitor.

    Michael

> I saw no, zero, none, not any change in the display.
> How about you?
>> 
>
>

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#1675 — Cute magnet story (was: lcd blah blah blah)

	I was doing system administration for an R&D group of about 40 
really world class computer scientists.  They all used Sun workstations,
ELC (the little box) or umm whatver the all-in-ones were, the monitor had the
motherboard in a slot behind it...  Anyway, one day I get a call, Marsha's 
monitor was broken.  These were 20 inch color monitors, the best graphics
in the business except for SGI and they weighed like 50 pounds, so I put
a spare on a cart and wheeled it down to Marsha's office.

	Sure enough, her monitor had all kinds of wierd distortion, so I turned
it off and swapped the spare in.  About an hour later I get a call from 
Marsha.  She wants to know when I'm going to fix her monitor.  Hmmmm.  I walk
down and look at the screen of the new unit, which has the same wierd distortion
the first one had.  

	Ok....  I scrounge up another 20 inch color Sun monitor, and wheel it
down to install it.  This time Marsha's in the office, and she feels bad about
making me come back again so she tries to help by moving the stuff on her
desk out of the way.  As soon as she moves her new high-intensity halogen 
desk lamp...the monitor picture goes back to its usual hi-res perfection.

	I stop unpacking the new one and move the lamp back.  Weird distortion.
Move it away, no problem.  We moved the lamp  to the other side of the desk
so she could have light *and* color graphics and I spent the next hour going
into people's offices with an old speaker magnet to show them the wierd
stuff magnets did to Sun monitors.

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#1676 — Re: Cute magnet story

On 11/18/2012 10:46 AM, the wharf rat wrote:
> 	I was doing system administration for an R&D group of about 40
> really world class computer scientists.  They all used Sun workstations,
> ELC (the little box) or umm whatver the all-in-ones were, the monitor had the
> motherboard in a slot behind it...  Anyway, one day I get a call, Marsha's
> monitor was broken.  These were 20 inch color monitors, the best graphics
> in the business except for SGI and they weighed like 50 pounds, so I put
> a spare on a cart and wheeled it down to Marsha's office.
>
> 	Sure enough, her monitor had all kinds of wierd distortion, so I turned
> it off and swapped the spare in.  About an hour later I get a call from
> Marsha.  She wants to know when I'm going to fix her monitor.  Hmmmm.  I walk
> down and look at the screen of the new unit, which has the same wierd distortion
> the first one had.
>
> 	Ok....  I scrounge up another 20 inch color Sun monitor, and wheel it
> down to install it.  This time Marsha's in the office, and she feels bad about
> making me come back again so she tries to help by moving the stuff on her
> desk out of the way.  As soon as she moves her new high-intensity halogen
> desk lamp...the monitor picture goes back to its usual hi-res perfection.
>
> 	I stop unpacking the new one and move the lamp back.  Weird distortion.
> Move it away, no problem.  We moved the lamp  to the other side of the desk
> so she could have light *and* color graphics and I spent the next hour going
> into people's offices with an old speaker magnet to show them the wierd
> stuff magnets did to Sun monitors.
>

These were LCD monitors?????

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#1678 — Re: Cute magnet story

In article <k8bj3t$7tf$1@dont-email.me>, mike  <ham789@netzero.net> wrote:
>On 11/18/2012 10:46 AM, the wharf rat wrote:
>> 	I was doing system administration for an R&D group of about 40
>These were LCD monitors?????

	No, of course not.  They were huge old style CRTs, with amazing
fidelity and superb resolution.  BFMs, lol.

	Heh, in 1992 the only things that had LCD displays was thermostats
and calculators.

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#1682 — Re: Cute magnet story

the wharf rat (wrat@panix.com) wrote:
> In article <k8bj3t$7tf$1@dont-email.me>, mike  <ham789@netzero.net> wrote:

> >On 11/18/2012 10:46 AM, the wharf rat wrote:
> >> 	I was doing system administration for an R&D group of about 40

> >These were LCD monitors?????

> 	No, of course not.  They were huge old style CRTs, with amazing
> fidelity and superb resolution.

***   I still use one at home and one at work. Each is a half-metre,
flat CRT, Sony Trinitron. I also have a Samsung LCD flat panel which is a
good monitor, but it can't hold a pixel to the Trinitrons. The main thing
I like is that I can use resolution settings on the CRTs that won't look
right on LCDs due to native resolution issues.


> 	Heh, in 1992 the only things that had LCD displays were 
> thermostats and calculators.

***   In addition were many professional pieces of equipment, especially
ones connected with the music and live performance industries.

-- 
         Richard Bonner
http://www.chebucto.ca/~ak621/DOS/

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#1681 — Re: Cute magnet story

mike (ham789@netzero.net) wrote:

> On 11/18/2012 10:46 AM, the wharf rat wrote:
(Snip)
> > ... I spent the next hour going into people's offices with an old
> > speaker magnet to show them the wierd stuff magnets did to Sun
> > monitors.

***   I used to like to toy with my friends by taking a bulk tape eraser,
turning it on and then immediately off while holding it against their CRT
TVs. It left the colours really screwed up. 

   After they freaked, I'd use the eraser again but as it was intended: 
passing it over the screen in circular motions while backing away from the
TV. (-: 

-- 
         Richard Bonner
http://www.chebucto.ca/~ak621/DOS/

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#1674

In article <k89foa$42g$1@dont-email.me>, mike  <ham789@netzero.net> wrote:
>>
>> 	If you can explain why an LCD wouldn't be effected by a strong
>> magnetic field given this I'm sure I'm not the only one who'd appreciate it.
>
>My sincerest apologies.  You are correct.  You cannot have a dynamic 
>electric field without creating a magnetic field somewhere in the universe.

	Oh, I see.  LCDs are immune to magnetic fields because of sarcasm.

>I'm confident that you and Mr. Maxwell can come up with equations describing
>how LCD's work in magnetic terms.

	Sorry.  He's busy fondling his silver hammer, and I have a report 
that's overdue.

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#1677

On Friday, November 16, 2012 12:39:12 PM UTC-6, the wharf rat wrote:
> In article <5932ee0e-a606-4bd7-b61c-be3b2d4e251a@googlegroups.com>,
> 
> Bob_Villa  <pheeh.zero@gmail.com> wrote:
> 
> >
> 
> >I never heard this so I tried a large magnet on my LCD...no distortion.  
> 
> >
> 
> 
> 
> 	Try a bigger magnet.  But be ready to by a new lcd.
> 
> 
> 
> 	The "liquid crystals" are affected by magnetic fields.  The LCDs
> 
> on certain medical equipment like MRIs have to be replaced periodically 
> 
> because they start to bleed green and purple lines.
> 
> 
> 
> 	Think about it.  They use magnetic fields to align the crystals to
> 
> pass light.  You just need a strong enough magnet.

I can feel the "pull" from the magnet because of the metal behind the screen...the "Medtronic" magnet has no affect on the screen graphics! These magnets are used to amplify pacemaker testing using telephony.

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#1679

In article <a189a96e-8a06-45ef-b967-35d3a64527af@googlegroups.com>,
Bob_Villa  <pheeh.zero@gmail.com> wrote:
>I can feel the "pull" from the magnet because of the metal behind the
>screen...the "Medtronic" magnet has no affect on the screen graphics!
>These magnets are used to amplify pacemaker testing using telephony.

	Well, maybe it takes a certain threshold, or maybe it requires
lengthy exposure.  They *are* sensitive because that's how the phenomenon
was discovered...  Hmmmm, I wonder what's the biggest magnet outside of
something like an MRI that would be handy...  The one that lifts the junk
cars at the scrap yard?  Wonder if they'd let me stand under it with a laptop.

	Hope my bridgework isn't magnetic...


	Heh, even if I'm totally wrong at least this thread was more fun then
diagnosing the latest variation of "My laptop makes a funny sound and 
smokes when I plug it in". :-)  

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