"Dave Plowman (News)" wrote in message
...
In article ,
Arfa Daily wrote:
Just had one of those weekly e-ads from a local department store that we
use sometimes, trumpeting the latest "Ultraslim LED TV" from Samsung.
Ha! I thought. I haven't heard anything about this. Is it OLED ? At
sizes up to over 50", that didn't seem likely, so I followed the links
to see what it was all about.
Seems that these sets still actually have an LCD display panel, but the
*backlighting* is LED ...
Yup. There are what can be accurately described as LED TVs on the horizon
- OLED. But are some way off in normal sizes at an affordable cost.
OK, so I can see that there are advantages size-wise - these things
are only 32mm thick - and also power consumption savings, as we all know
that flourescent tube backlighting is very inefficient, but is it right
to actually call these "LED TVs"
Who says fluorescent is inefficient? LED could be better if you could turn
off those in the dark parts of the picture - but no claims for that. Other
problem with LEDs is producing a continuous spectrum smooth white light -
needed to give all the colours from LCD.
? Seems like a bit of a deliberately misleading use of the terminology
to me - or is it maybe just me being a picky grumpy old sod ? d:~)
Might as well claim any TV is LED - if it has an LED warning light. ;-)
--
*Who is this General Failure chap anyway - and why is he reading my HD? *
Dave Plowman London SW
To e-mail, change noise into sound.
I'm not disputing - not that anyone is suggesting that I am of course -
that this is very possibly a distinct improvement over the existing
backlight technology. I haven't actually seen one 'in the flesh' yet, but I
will look out for one next time I am in JL or Waitrose. I am expecting, as
it is from Sammy, that it will probably be very good. But following up on
Tim's link to "what Samsung say ..." I am very surprised that as a reputable
company, they have made such a deliberate attempt to 'fuzz the edges' on
this, and go out of their way to suggest that it is something other than an
LCD screen.
And as to who says that flourescent backlighting is inefficient - well I do,
actually. I have this morning been mending a bunch of LCD TV power supplies
that I do regularly for a company. They come from a manufacturer that
supplies them to many TV manufacturers for use in their LCD TV sets. The
main - as in biggest, chunkiest and most heatsunk - rail, is without doubt
the 24v one that feeds mostly the backlights. A small amount of power is
also drawn from this rail by the audio output stages, but by far the lion's
share goes to the backlight inverter.
This rail is designed to supply up to 5 amps, and an average sized LCD TV -
say a 28 or 32" - pulls around 4 amps off it to run the backlights. That's
100 watts. An awful lot of power to produce the amount of light that the
tubes do. A considerable amount of that input power goes to losses in the
inverter board, which runs pretty hot, and also to losses in the tubes,
which can get hot enough to be uncomfortable to touch. The LCD TV that I
have on my kitchen wall produces enough heat from the backlights, that you
can feel it on your face, rolling off the front of the screen as you walk
past.
If the LED backlighting that Sammy are using, is as bright or brighter than
the flourescent equivalent, I would be very surprised if it was consuming
more than 20 watts, even with the whole array on.
Arfa