DXers rejoice! The end of plasma TVs

[ChrisSmolinski]

The end of plasma TVs: http://blogs.wsj.com/digits/2014/07/03/plasma-tvs-no-more/?mod=ST1

[redhat]

One of the last remaining plasma display makers –Samsung SDI, an affiliate of the South Korean technology giant Samsung Electronics –announced this week it will cease making the flat-screens used in TVs in November, citing poor demand.

That leaves just crosstown rival LG Electronics, a minor player in the sector, as the sole company in the world still making plasma display televisions.

A spokeswoman for LG said the company will supply plasma TVs “as long as there is demand.” But even so, LG notes that plasma TVs only account for a single-digit percentage of the company’s TV revenue these days.

Japan’s Panasonic, once the biggest player in the field, took much of the steam away from plasma TVs when it signaled a complete withdrawal last year.

    And then there was one.
    LG

Plasma screens were initially touted as the next-generation TV display technology in the early to mid 2000s to replace the thick, cathode-ray tube TVs.  They competed head-to-head with liquid crystal displays, but manufacturers had a hard time mass producing smaller screens at higher resolution and ultimately LCDs began to be adopted more widely in consumer electronics.

Some analysts argued that plasma TVs had more advantages over LCDs including better viewing angles and faster response time.

But LCD technology has improved significantly over time and plasma displays became less attractive.

In the first quarter, only 2 million units of PDP TVs were shipped globally, representing a 16% drop from a year ago, according to research firm IHS. This compares with 47 million LCD TV units shipped during the same period.

Samsung SDI had started out as a display supplier in the 1970s starting with CRTs, developing into a maker of plasma and liquid-crystal-display screens over the years. Now, Samsung’s main display unit, called Samsung Display is mass producing more advanced organic light emitting diode (OLED) screens which are thinner and more energy efficient than LCDs. Many industry experts believe that OLED will ultimately replace LCD technology though manufacturers are having difficulty producing OLED screens in mass volume, especially for large televisions.

In an interview with The Wall Street Journal last year, Samsung SDI’s chief executive said the life span of plasma panels is nearing an end and it will gradually shift production.

 – Juro Osawa in Hong Kong contributed to this article.

Mu guess is ROHS has something to do with their demise, as does the difficulty of getting energy star certification.  Any way you slice it, they still need phosphorus and a handful of other nasty chemicals to make the panels.  That coupled with the power consumption makes the sets anything but green.  They still produce a picture that in my opinion LCD and LED will never touch.

I was recently at an electronics store and they had one of the new OLED TV's on display.  It looked like a1970's TV with a flat red gun

+-RH

[BoomboxDX]

A nearby neighbor had a plasma TV that radiated horrific hash noise all over HF, from below 49 meters all the way up to above 20 meters. Just awful. Even CW couldn't cut through it.  They were at least a couple hundred feet away.

Then it stopped. The person with the TV in question moved out. Yay.

The person who owns the house has a monstrous TV, which produces some of the same noise, but it's nowhere near as bad. Not sure what kind of flatscreen it is, but as long as it doesn't obliterate the HF like the other TV did, I won't complain.

[ka1iic]

I guess it depends on the TV... We have a Visio 48inch plasma job here and it cause minimal problems but one of the neighbours has a set that just kills most of everything...  power consumption is horrible and I have used it to warm my hands in the winter time... no joke it throws a lot of heat.  You can even feel it when passing near by it...

[Tom S]

What that article didn't mention was the high failure rate of plasma TV's.  I think I read somewhere that the average life of one was about 2 years.

[Nella F.]

What that article didn't mention was the high failure rate of plasma TV's.  I think I read somewhere that the average life of one was about 2 years.

Two years! My JVC tube, 14 years old, is still working. Don't know what I'll buy when it dies: A new t.v. or one of those bumper stickers, you know " kill your t.v." or whatever.

[redhat]

One of the fatal flaws of plasma technology is the short life of the panel.  The typical number I used to hear was that the panel will go to half brightness in around 2 years of use.  This is mainly due to ion bombardment of the phosphorus in the individual plasma cells.  Anyone who used to work on color tv's remembers the "ion trap" magnet that was strapped around the picture tube neck.  It's job was to deflect the relatively heavy ions and keep them from bombarding the center of the screen and causing a dark spot.  Because these ions are heavier than electrons, they are not effectively deflected by the deflection system, and thus would repeatedly strike the same area of the screen, causing accelerated wear.  The same thing happens in plasma TV's.  Each plasma "cell" has a low pressure gas, usually xenon and kryton if I remember correctly, an electron gun and the phosphorus.  When the cell switches on, the gas is ionized, and illuminates the phosphorus by bombarding it with electrons, and you guessed it, ions.  I theorize that this is the primary mechanism of wear in the panel.

The reason the panels radiate so much is the length of the conductive strips that connect all the cells in row and column fashion.  on a 60" set, some of those wires are three feet long, and carry large amounts of current when the cells are in conduction.  Because shielding the glass would reduce the brightness of the set, its very difficult to keep the EMI in check.  The best manufacturers can do is soften the initial conduction pulse of the cell as it switches on, which also affects brightness.  Just like a switch mode power supply, the cells are either on or off.  To get variations in brightness, the percentage of time the cell is lit is varied, and our eyes fill in the rest.  DLP systems work on the same principles.

I could be wrong, but after being around a few of them, that's my theory about them.

+-RH

[Tom S]

On another thread here I mentioned using an LCD TV as a computer monitor using the VGA input.  It's been working great so far and I haven't noticed any EMI coming from it.  One project for the near future is to put up a TV antenna so I'll be able to watch TV in the shack.