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About LEDs and LCDs

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  About LEDs and LCDs Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> - 2017-10-09 17:58 +0000
    Re: About LEDs and LCDs John Larkin <jjlarkin@highland_snip_technology.com> - 2017-10-09 11:20 -0700
      Re: About LEDs and LCDs Klaus Kragelund <klauskvik@hotmail.com> - 2017-10-09 11:42 -0700
        Re: About LEDs and LCDs Jan Panteltje <pNaonStpealmtje@yahoo.com> - 2017-10-09 19:24 +0000
          Re: About LEDs and LCDs klaus.kragelund@gmail.com - 2017-10-09 13:13 -0700
      Re: About LEDs and LCDs Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> - 2017-10-09 19:08 +0000
    Re: About LEDs and LCDs bitrex <bitrex@de.lete.earthlink.net> - 2017-10-09 16:28 -0400
      Re: About LEDs and LCDs Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> - 2017-10-10 08:16 +0000
      Re: About LEDs and LCDs Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> - 2017-10-10 08:16 +0000
        Re: About LEDs and LCDs bitrex <bitrex@de.lete.earthlink.net> - 2017-10-10 08:06 -0400
          Re: About LEDs and LCDs Jan Panteltje <pNaonStpealmtje@yahoo.com> - 2017-10-10 15:08 +0000
            Re: About LEDs and LCDs Jan Panteltje <pNaonStpealmtje@yahoo.com> - 2017-10-10 15:13 +0000
              Re: About LEDs and LCDs Allan Herriman <allanherriman@hotmail.com> - 2017-10-10 23:21 +0000
            Re: About LEDs and LCDs Clifford Heath <no.spam@please.net> - 2017-10-11 10:58 +1100
              Re: About LEDs and LCDs Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-10-10 17:10 -0700
              Re: About LEDs and LCDs Jan Panteltje <pNaonStpealmtje@yahoo.com> - 2017-10-11 14:40 +0000
                Re: About LEDs and LCDs jack4747@gmail.com - 2017-10-11 07:45 -0700
                  Re: About LEDs and LCDs Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-10-11 15:02 +0000
                Re: About LEDs and LCDs krw@notreal.com - 2017-10-11 21:03 -0400
                  Re: About LEDs and LCDs Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-10-12 07:19 +0000
                    Re: About LEDs and LCDs rickman <gnuarm@gmail.com> - 2017-10-12 13:07 -0400
                      Re: About LEDs and LCDs Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> - 2017-10-12 17:18 +0000
                        Re: About LEDs and LCDs kevin93 <kevin@whitedigs.com> - 2017-10-12 19:30 -0700
                      Re: About LEDs and LCDs krw@notreal.com - 2017-10-12 21:28 -0400
                    Re: About LEDs and LCDs krw@notreal.com - 2017-10-12 20:55 -0400
                Re: About LEDs and LCDs Jasen Betts <jasen@xnet.co.nz> - 2017-10-12 04:22 +0000
            Re: About LEDs and LCDs Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-10-10 17:12 -0700
              Re: About LEDs and LCDs Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-10-11 14:41 +0000
    Re: About LEDs and LCDs Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2017-10-10 14:56 +0100
      Re: About LEDs and LCDs Jan Panteltje <pNaonStpealmtje@yahoo.com> - 2017-10-10 14:20 +0000

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#480933 — About LEDs and LCDs

My lab power supply display slowly turned black during the last few month...:
 http://panteltje.com/pub/LCD_turning_black_IMG_6329.JPG

It is an old design and OK after all those years, but why does this process happen?
I once had an LCD watch and when sitting in the sun outside all of the sudden it turned black..
was very hot, bought a new one.
This thing has not been hot.

So, anyways had some other ones that did not fit, had a different driver, did not want to re-write the software, thing is way too good,
so ebay: found a Geeetech Yellow backlight LCD 1602 16x2 Characters display that claimed to have the same driver chip,
and same mechanical outline, start bid was 99 cents, so I did and got it, shipping 1 dollar.
Installed it yesterday.
Works perfectly, OR???
WOW such a bright backlight, blinding, switched it off again.
Checked the datasheet, maybe it needed a series resistor ??
Nope, 5V on the LED pins, resistor is on the module.
Still could not believe it, looked like a reading light, measured the current:
10 mA

Now you guys talk about LED aging, but it seems the newer ones are so good, those need attenuation.
Added 270 Ohm in series, now it is OK.
It is still bright in the evening, but no eye damage this way.

For new designs I only use OLED.

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#480937

On Mon, 09 Oct 2017 17:58:51 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:

>My lab power supply display slowly turned black during the last few month...:
> http://panteltje.com/pub/LCD_turning_black_IMG_6329.JPG
>
>It is an old design and OK after all those years, but why does this process happen?
>I once had an LCD watch and when sitting in the sun outside all of the sudden it turned black..
>was very hot, bought a new one.
>This thing has not been hot.
>
>So, anyways had some other ones that did not fit, had a different driver, did not want to re-write the software, thing is way too good,
>so ebay: found a Geeetech Yellow backlight LCD 1602 16x2 Characters display that claimed to have the same driver chip,
>and same mechanical outline, start bid was 99 cents, so I did and got it, shipping 1 dollar.
>Installed it yesterday.
>Works perfectly, OR???
>WOW such a bright backlight, blinding, switched it off again.
>Checked the datasheet, maybe it needed a series resistor ??
>Nope, 5V on the LED pins, resistor is on the module.
>Still could not believe it, looked like a reading light, measured the current:
>10 mA
>
>Now you guys talk about LED aging, but it seems the newer ones are so good, those need attenuation.
>Added 270 Ohm in series, now it is OK.
>It is still bright in the evening, but no eye damage this way.

Our front-panel LEDs keep getting brighter as the diodes improve.
We've had to change resistors after customers complained. Blue LEDs
especially.

>
>For new designs I only use OLED.

Don't OLED pixels wear out? Like the old EL displays.



-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#480938

AFAIK OLEDs have bad lifetime 

We use Everlight, but cannot get lifetime data, so probably moving to Osram or others that do provide data

LED lifetime can be optimized by running at the best efficiency point and driving it with PWM. Downside is higher drop resistance losses

Intensity differences between batches can be calibrated out with a more clever driver design 

Cheers

Klaus 

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#480943

On a sunny day (Mon, 9 Oct 2017 11:42:24 -0700 (PDT)) it happened Klaus
Kragelund <klauskvik@hotmail.com> wrote in
<2e42c03e-f97f-47cf-baa2-8ff508a77e69@googlegroups.com>:

>AFAIK OLEDs have bad lifetime 
>
>We use Everlight, but cannot get lifetime data, so probably moving to Osram or others that do provide data
>
>LED lifetime can be optimized by running at the best efficiency point and driving it with PWM. Downside is higher drop
>resistance losses
>
>Intensity differences between batches can be calibrated out with a more clever driver design 
>
>Cheers
>
>Klaus 

Define 'bad lifetime'.
I do not see any degradation after 3 years 24/7 with cheap ebay OLEDs.
LCDs are always a problem, contrast, backlight needs to be adjustable,
or switchable, bad viewing angle.
You can run OLEDs at low brightness too, not sure if that extends life though.

Difference with LCD and backlight is that only the segments that are 'on' draw current, and then only as much as the selected brightness.

But sure there are applications that still need LCD, sunlight readable color monitors, but try finding a good cheap one.
But for equipment used in house of normal lighting conditions OLED is the way to go.

There is an issue in color OLEDs with the 3 primary colors fading in a different way over time,
to fix that I think LG uses white OLEDs with color filters for R. G, B,
that way the white balance stays the same over time, but the filters take away light, so it is basically less efficient.

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#480947

Just selected first random OLED display:

http://www.newhavendisplay.com/specs/NHD-2.23-12832UCB3.pdf

10k hours lifetime

Just enough for 1 year

Our products must have minimum 100k hours lifetime

Might be that I just "found" a bad reference

Cheers 

Klaus 

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#480940

On a sunny day (Mon, 09 Oct 2017 11:20:26 -0700) it happened John Larkin
<jjlarkin@highland_snip_technology.com> wrote in
<7afntclrcccqva2kfb3b7n89vttto0mj4a@4ax.com>:

>Don't OLED pixels wear out? Like the old EL displays.

The blue OLEDs I have have now about 3 years of 24/7 use,
no problem.
Always have those on minimum brightness.
Have not used color OLEDs yet.
The OLEDs are getting cheaper each day, use less power than a LCD,
have a better viewing angle, are just as bright, good readable in sunlight too.
The small 128x64 ones I use have an I2C interface,
simpler than those 8 or 4 bit bit LCD interfaces.

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#480948

On 10/09/2017 01:58 PM, Jan Panteltje wrote:
> My lab power supply display slowly turned black during the last few month...:
>   http://panteltje.com/pub/LCD_turning_black_IMG_6329.JPG
> 
> It is an old design and OK after all those years, but why does this process happen?
> I once had an LCD watch and when sitting in the sun outside all of the sudden it turned black..
> was very hot, bought a new one.
> This thing has not been hot.
> 
> So, anyways had some other ones that did not fit, had a different driver, did not want to re-write the software, thing is way too good,
> so ebay: found a Geeetech Yellow backlight LCD 1602 16x2 Characters display that claimed to have the same driver chip,
> and same mechanical outline, start bid was 99 cents, so I did and got it, shipping 1 dollar.
> Installed it yesterday.
> Works perfectly, OR???
> WOW such a bright backlight, blinding, switched it off again.
> Checked the datasheet, maybe it needed a series resistor ??
> Nope, 5V on the LED pins, resistor is on the module.
> Still could not believe it, looked like a reading light, measured the current:
> 10 mA
> 
> Now you guys talk about LED aging, but it seems the newer ones are so good, those need attenuation.
> Added 270 Ohm in series, now it is OK.
> It is still bright in the evening, but no eye damage this way.
> 
> For new designs I only use OLED.
> 

The display module looks a lot like these I have in my bin (though I 
think they're 1 line):

<https://www.dropbox.com/s/73estagp6emqpfv/Photo%20Oct%2009%2C%204%2020%2034%20PM.jpg?dl=0>

<https://www.dropbox.com/s/pzgvqxzo3ivhu2j/Photo%20Oct%2009%2C%204%2020%2044%20PM.jpg?dl=0>

No backlight, just silver reflective tape on the reverse; it can be 
pulled off and there are terminals on the PCB and room to slide a strip 
of EL material underneath.

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#480975

On a sunny day (Mon, 9 Oct 2017 13:13:22 -0700 (PDT)) it happened
klaus.kragelund@gmail.com wrote in
<40650fb5-4f52-421b-bc23-feea15a3e748@googlegroups.com>:

>Just selected first random OLED display:
>
>http://www.newhavendisplay.com/specs/NHD-2.23-12832UCB3.pdf
>
>10k hours lifetime
>
>Just enough for 1 year
>
>Our products must have minimum 100k hours lifetime
>
>Might be that I just "found" a bad reference
>
>Cheers 
>
>Klaus 

OK, this has been running 24/7 as my alarm clock now since about 01/07/2014
 http://www.ebay.com/itm/171069574803
  in this project:
   http://panteltje.com/panteltje/pic/gm_pic2/
It is on now, and charging at the same time.
That is about 3 years or 24 * 365 *3 = 26,280 hours.
It is running at lowest brightness, and that is bright enough.
I do not see (but have not measured with a light meter) any degradation or other defects.

I guess luck is with me, as the lipo in it has now been recharged 365 * 3 = 1095 times,
something that is not possible either ;-)

I have more of these displays in use, for example:
  http://panteltje.com/pub/SWR_bridge_IMG_5032.JPG
   very good readable in bright sunlight, even with the protection foil.


?

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#480976

On a sunny day (Mon, 9 Oct 2017 16:28:51 -0400) it happened bitrex
<bitrex@de.lete.earthlink.net> wrote in <8_QCB.1$Z%2.0@fx43.iad>:

>On 10/09/2017 01:58 PM, Jan Panteltje wrote:
>> My lab power supply display slowly turned black during the last few month...:
>>   http://panteltje.com/pub/LCD_turning_black_IMG_6329.JPG
>> 
>> It is an old design and OK after all those years, but why does this process happen?
>> I once had an LCD watch and when sitting in the sun outside all of the sudden it turned black..
>> was very hot, bought a new one.
>> This thing has not been hot.
>> 
>> So, anyways had some other ones that did not fit, had a different driver, did not want to re-write the software, thing is way
>> too good,
>> so ebay: found a Geeetech Yellow backlight LCD 1602 16x2 Characters display that claimed to have the same driver chip,
>> and same mechanical outline, start bid was 99 cents, so I did and got it, shipping 1 dollar.
>> Installed it yesterday.
>> Works perfectly, OR???
>> WOW such a bright backlight, blinding, switched it off again.
>> Checked the datasheet, maybe it needed a series resistor ??
>> Nope, 5V on the LED pins, resistor is on the module.
>> Still could not believe it, looked like a reading light, measured the current:
>> 10 mA
>> 
>> Now you guys talk about LED aging, but it seems the newer ones are so good, those need attenuation.
>> Added 270 Ohm in series, now it is OK.
>> It is still bright in the evening, but no eye damage this way.
>> 
>> For new designs I only use OLED.
>> 
>
>The display module looks a lot like these I have in my bin (though I 
>think they're 1 line):
>
><https://www.dropbox.com/s/73estagp6emqpfv/Photo%20Oct%2009%2C%204%2020%2034%20PM.jpg?dl=0>
>
><https://www.dropbox.com/s/pzgvqxzo3ivhu2j/Photo%20Oct%2009%2C%204%2020%2044%20PM.jpg?dl=0>
>
>No backlight, just silver reflective tape on the reverse; it can be 
>pulled off and there are terminals on the PCB and room to slide a strip 
>of EL material underneath.

Ah, yes, that is that other controller,
I have a few of those in other projects, but with backlight.

This one I replaced uses the KS0066 + KS0065 LCD controller (2 chips).

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#480979

On 10/10/2017 04:16 AM, Jan Panteltje wrote:

>> The display module looks a lot like these I have in my bin (though I
>> think they're 1 line):
>>
>> <https://www.dropbox.com/s/73estagp6emqpfv/Photo%20Oct%2009%2C%204%2020%2034%20PM.jpg?dl=0>
>>
>> <https://www.dropbox.com/s/pzgvqxzo3ivhu2j/Photo%20Oct%2009%2C%204%2020%2044%20PM.jpg?dl=0>
>>
>> No backlight, just silver reflective tape on the reverse; it can be
>> pulled off and there are terminals on the PCB and room to slide a strip
>> of EL material underneath.
> 
> Ah, yes, that is that other controller,
> I have a few of those in other projects, but with backlight.
> 
> This one I replaced uses the KS0066 + KS0065 LCD controller (2 chips).
> 

This type of module (with one, two, or four lines) plus EL backlight 
underneath seems to have been the illuminated display of choice in a lot 
of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s. 
On the plus side EL material degrades gradually; I'd estimate it has a 
"time to half brightness" of around 15 years run a couple hours a day.

On the downside EL material isn't that bright to begin with, and it 
seems usually the switching transistor or electrolytic caps in the 
blocking oscillator used to generate the HV go kaput before the 
backlight does.

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#480989

On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
<bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:

>This type of module (with one, two, or four lines) plus EL backlight 
>underneath seems to have been the illuminated display of choice in a lot 
>of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s. 
>On the plus side EL material degrades gradually; I'd estimate it has a 
>"time to half brightness" of around 15 years run a couple hours a day.
>
>On the downside EL material isn't that bright to begin with, and it 
>seems usually the switching transistor or electrolytic caps in the 
>blocking oscillator used to generate the HV go kaput before the 
>backlight does.

There is actually an other argument against LCD panels,
and that is polarization.
Try looking at one through a pair of Polaroid glasses, and then tilt you head.
My LDC monitor is 45 degrees polarized it seems, and will then go black,
the small multi-line LCDs 90 degrees.

That is also the reason airline pilots do not wear Polaroid sunglasses,
in these days with glass-cockpits it would make reading instruments problematic if you look sideways etc.

So, OLED is is ;-)

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#480990

On a sunny day (Tue, 10 Oct 2017 15:08:01 GMT) it happened Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote in <orinok$j1q$1@adenine.netfront.net>:

>On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
><bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
>
>>This type of module (with one, two, or four lines) plus EL backlight 
>>underneath seems to have been the illuminated display of choice in a lot 
>>of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s. 
>>On the plus side EL material degrades gradually; I'd estimate it has a 
>>"time to half brightness" of around 15 years run a couple hours a day.
>>
>>On the downside EL material isn't that bright to begin with, and it 
>>seems usually the switching transistor or electrolytic caps in the 
>>blocking oscillator used to generate the HV go kaput before the 
>>backlight does.
>
>There is actually an other argument against LCD panels,
>and that is polarization.
>Try looking at one through a pair of Polaroid glasses, and then tilt you head.
>My LDC monitor is 45 degrees polarized it seems, and will then go black,
>the small multi-line LCDs 90 degrees.
>
>That is also the reason airline pilots do not wear Polaroid sunglasses,
>in these days with glass-cockpits it would make reading instruments problematic if you look sideways etc.
>
>So, OLED is is ;-)

Or not, my little OLED displays also go black at 90 degrees...
Where does that leave us now :-)

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#481023

On Tue, 10 Oct 2017 15:13:31 +0000, Jan Panteltje wrote:

> On a sunny day (Tue, 10 Oct 2017 15:08:01 GMT) it happened Jan Panteltje
> <pNaonStpealmtje@yahoo.com> wrote in
> <orinok$j1q$1@adenine.netfront.net>:
> 
>>On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
>><bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
>>
>>>This type of module (with one, two, or four lines) plus EL backlight
>>>underneath seems to have been the illuminated display of choice in a
>>>lot of pro audio equipment, synthesizers, etc. in the 1980s and early
>>>1990s.
>>>On the plus side EL material degrades gradually; I'd estimate it has a
>>>"time to half brightness" of around 15 years run a couple hours a day.
>>>
>>>On the downside EL material isn't that bright to begin with, and it
>>>seems usually the switching transistor or electrolytic caps in the
>>>blocking oscillator used to generate the HV go kaput before the
>>>backlight does.
>>
>>There is actually an other argument against LCD panels,
>>and that is polarization.
>>Try looking at one through a pair of Polaroid glasses, and then tilt you
>>head.
>>My LDC monitor is 45 degrees polarized it seems, and will then go black,
>>the small multi-line LCDs 90 degrees.
>>
>>That is also the reason airline pilots do not wear Polaroid sunglasses,
>>in these days with glass-cockpits it would make reading instruments
>>problematic if you look sideways etc.
>>
>>So, OLED is is ;-)
> 
> Or not, my little OLED displays also go black at 90 degrees...
> Where does that leave us now :-)

They put polarisers on the OLEDs to cut down on reflected light to 
improve the "blackness" and hence contrast.
Unlike an LCD, it would work without the polariser.

Allan

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#481026

On 11/10/17 02:08, Jan Panteltje wrote:
> On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
> <bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
> 
>> This type of module (with one, two, or four lines) plus EL backlight
>> underneath seems to have been the illuminated display of choice in a lot
>> of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s.
>> On the plus side EL material degrades gradually; I'd estimate it has a
>> "time to half brightness" of around 15 years run a couple hours a day.
>>
>> On the downside EL material isn't that bright to begin with, and it
>> seems usually the switching transistor or electrolytic caps in the
>> blocking oscillator used to generate the HV go kaput before the
>> backlight does.
> 
> There is actually an other argument against LCD panels,
> and that is polarization.
> Try looking at one through a pair of Polaroid glasses, and then tilt you head.

I recall stepping into the lift lobby of a high-rise,
and wondering why they had no directory to tell me what
floor to go to. Then I took off my sunnies, and realized
that the black rectangles on the wall weren't architectural
features, but large TV screens mounted vertically, so my
sunnies completely blocked the light from the screen.
Strange experience.It made me think that screens should be
made in various polarisations to suit the application.

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#481028

Den onsdag den 11. oktober 2017 kl. 01.58.27 UTC+2 skrev Clifford Heath:
> On 11/10/17 02:08, Jan Panteltje wrote:
> > On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
> > <bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
> > 
> >> This type of module (with one, two, or four lines) plus EL backlight
> >> underneath seems to have been the illuminated display of choice in a lot
> >> of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s.
> >> On the plus side EL material degrades gradually; I'd estimate it has a
> >> "time to half brightness" of around 15 years run a couple hours a day.
> >>
> >> On the downside EL material isn't that bright to begin with, and it
> >> seems usually the switching transistor or electrolytic caps in the
> >> blocking oscillator used to generate the HV go kaput before the
> >> backlight does.
> > 
> > There is actually an other argument against LCD panels,
> > and that is polarization.
> > Try looking at one through a pair of Polaroid glasses, and then tilt you head.
> 
> I recall stepping into the lift lobby of a high-rise,
> and wondering why they had no directory to tell me what
> floor to go to. Then I took off my sunnies, and realized
> that the black rectangles on the wall weren't architectural
> features, but large TV screens mounted vertically, so my
> sunnies completely blocked the light from the screen.
> Strange experience.It made me think that screens should be
> made in various polarisations to suit the application.

https://youtu.be/26qYrSNYJXM?t=3m10s

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#481061

On a sunny day (Wed, 11 Oct 2017 10:58:19 +1100) it happened Clifford Heath
<no.spam@please.net> wrote in <y8dDB.829$US1.674@fx15.iad>:

>On 11/10/17 02:08, Jan Panteltje wrote:
>> On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
>> <bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
>> 
>>> This type of module (with one, two, or four lines) plus EL backlight
>>> underneath seems to have been the illuminated display of choice in a lot
>>> of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s.
>>> On the plus side EL material degrades gradually; I'd estimate it has a
>>> "time to half brightness" of around 15 years run a couple hours a day.
>>>
>>> On the downside EL material isn't that bright to begin with, and it
>>> seems usually the switching transistor or electrolytic caps in the
>>> blocking oscillator used to generate the HV go kaput before the
>>> backlight does.
>> 
>> There is actually an other argument against LCD panels,
>> and that is polarization.
>> Try looking at one through a pair of Polaroid glasses, and then tilt you head.
>
>I recall stepping into the lift lobby of a high-rise,
>and wondering why they had no directory to tell me what
>floor to go to. Then I took off my sunnies, and realized
>that the black rectangles on the wall weren't architectural
>features, but large TV screens mounted vertically, so my
>sunnies completely blocked the light from the screen.
>Strange experience.It made me think that screens should be
>made in various polarisations to suit the application.

I have several pairs of sunglasses... only one polarized.

Wonder what happens when driving those Teslas with LCD dashboard..
Anybody driving Teslas here???

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#481063

On Wednesday, October 11, 2017 at 4:40:28 PM UTC+2, Jan Panteltje wrote:
> On a sunny day (Wed, 11 Oct 2017 10:58:19 +1100) it happened Clifford Heath
> <no.spam@please.net> wrote in <y8dDB.829$US1.674@fx15.iad>:
> 
> >On 11/10/17 02:08, Jan Panteltje wrote:
> >> On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
> >> <bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
> >> 
> >>> This type of module (with one, two, or four lines) plus EL backlight
> >>> underneath seems to have been the illuminated display of choice in a lot
> >>> of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s.
> >>> On the plus side EL material degrades gradually; I'd estimate it has a
> >>> "time to half brightness" of around 15 years run a couple hours a day.
> >>>
> >>> On the downside EL material isn't that bright to begin with, and it
> >>> seems usually the switching transistor or electrolytic caps in the
> >>> blocking oscillator used to generate the HV go kaput before the
> >>> backlight does.
> >> 
> >> There is actually an other argument against LCD panels,
> >> and that is polarization.
> >> Try looking at one through a pair of Polaroid glasses, and then tilt you head.
> >
> >I recall stepping into the lift lobby of a high-rise,
> >and wondering why they had no directory to tell me what
> >floor to go to. Then I took off my sunnies, and realized
> >that the black rectangles on the wall weren't architectural
> >features, but large TV screens mounted vertically, so my
> >sunnies completely blocked the light from the screen.
> >Strange experience.It made me think that screens should be
> >made in various polarisations to suit the application.
> 
> I have several pairs of sunglasses... only one polarized.
> 
> Wonder what happens when driving those Teslas with LCD dashboard..
> Anybody driving Teslas here???

Are they OLED?
Beacause, AFAIK, OLED are not polarized...

Bye Jack

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#481064

On a sunny day (Wed, 11 Oct 2017 07:45:02 -0700 (PDT)) it happened
jack4747@gmail.com wrote in
<d210fca0-8f1c-4dc5-bd6f-c958ddbc069f@googlegroups.com>:

>On Wednesday, October 11, 2017 at 4:40:28 PM UTC+2, Jan Panteltje wrote:
>> On a sunny day (Wed, 11 Oct 2017 10:58:19 +1100) it happened Clifford Heath
>> <no.spam@please.net> wrote in <y8dDB.829$US1.674@fx15.iad>:
>> 
>> >On 11/10/17 02:08, Jan Panteltje wrote:
>> >> On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
>> >> <bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
>> >> 
>> >>> This type of module (with one, two, or four lines) plus EL backlight
>> >>> underneath seems to have been the illuminated display of choice in a lot
>> >>> of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s.
>> >>> On the plus side EL material degrades gradually; I'd estimate it has a
>> >>> "time to half brightness" of around 15 years run a couple hours a day.
>> >>>
>> >>> On the downside EL material isn't that bright to begin with, and it
>> >>> seems usually the switching transistor or electrolytic caps in the
>> >>> blocking oscillator used to generate the HV go kaput before the
>> >>> backlight does.
>> >> 
>> >> There is actually an other argument against LCD panels,
>> >> and that is polarization.
>> >> Try looking at one through a pair of Polaroid glasses, and then tilt you head.
>> >
>> >I recall stepping into the lift lobby of a high-rise,
>> >and wondering why they had no directory to tell me what
>> >floor to go to. Then I took off my sunnies, and realized
>> >that the black rectangles on the wall weren't architectural
>> >features, but large TV screens mounted vertically, so my
>> >sunnies completely blocked the light from the screen.
>> >Strange experience.It made me think that screens should be
>> >made in various polarisations to suit the application.
>> 
>> I have several pairs of sunglasses... only one polarized.
>> 
>> Wonder what happens when driving those Teslas with LCD dashboard..
>> Anybody driving Teslas here???
>
>Are they OLED?

Don't know.


>Beacause, AFAIK, OLED are not polarized...

Mine are... (the little blue ones).
Somebody else already explained why.

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#481137

On Wed, 11 Oct 2017 14:40:07 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

>On a sunny day (Wed, 11 Oct 2017 10:58:19 +1100) it happened Clifford Heath
><no.spam@please.net> wrote in <y8dDB.829$US1.674@fx15.iad>:
>
>>On 11/10/17 02:08, Jan Panteltje wrote:
>>> On a sunny day (Tue, 10 Oct 2017 08:06:38 -0400) it happened bitrex
>>> <bitrex@de.lete.earthlink.net> wrote in <tJ2DB.15074$Ov1.863@fx30.iad>:
>>> 
>>>> This type of module (with one, two, or four lines) plus EL backlight
>>>> underneath seems to have been the illuminated display of choice in a lot
>>>> of pro audio equipment, synthesizers, etc. in the 1980s and early 1990s.
>>>> On the plus side EL material degrades gradually; I'd estimate it has a
>>>> "time to half brightness" of around 15 years run a couple hours a day.
>>>>
>>>> On the downside EL material isn't that bright to begin with, and it
>>>> seems usually the switching transistor or electrolytic caps in the
>>>> blocking oscillator used to generate the HV go kaput before the
>>>> backlight does.
>>> 
>>> There is actually an other argument against LCD panels,
>>> and that is polarization.
>>> Try looking at one through a pair of Polaroid glasses, and then tilt you head.
>>
>>I recall stepping into the lift lobby of a high-rise,
>>and wondering why they had no directory to tell me what
>>floor to go to. Then I took off my sunnies, and realized
>>that the black rectangles on the wall weren't architectural
>>features, but large TV screens mounted vertically, so my
>>sunnies completely blocked the light from the screen.
>>Strange experience.It made me think that screens should be
>>made in various polarisations to suit the application.
>
>I have several pairs of sunglasses... only one polarized.
>
>Wonder what happens when driving those Teslas with LCD dashboard..
>Anybody driving Teslas here???

I believe Automotive LCD are circularly polarized for this reason.
Cell phones are, too.

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#481152

On a sunny day (Wed, 11 Oct 2017 21:03:52 -0400) it happened krw@notreal.com
wrote in <ogfttc1aq3rad1n5uushlcvada538p7rr9@4ax.com>:

>I believe Automotive LCD are circularly polarized for this reason.
>Cell phones are, too.

Not my old Nokia..
My HTC android changes from almost normal to purple (rotate glasses one way)  to greenish (the other way),
much looks BW and some text dis-appears.
Other Nokia goes black at 45 degrees.

Yours?

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