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Re: About LEDs and LCDs

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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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Thread

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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