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keeping up - leds for back lighting flat screens

“Backlighting helps create contrast on LCD screens by illuminating the background so that the foreground appears sharper.

“The technology, LED (light emitting diode), is new to the marketplace for a few reasons, mainly cost. A user would have to pay two or three times as much for an LCD TV that uses an LED backlight instead of a traditional cold cathode fluorescent lamp (CCFL) backlight, for example.

“But prices have come down to the point where most technologies start to break into the market, [...]”
—
“ LED backlights are making headway in laptops because costs are coming down and LEDs use less power, saving battery life. In laptops, power savings is far more important than plug-in devices, and screens tend to be a major battery drainer. LED backlights reduce power usage by at least 10 percent compared to older technologies, Liu said.”

Another view on the technology as applied to televisions:

“What are the biggest failings of LCD technology? Black level and color accuracy. More minor issues, but ones that get mentioned a lot by LCD owners, are light bleed and backlight unevenness. LED backlighting cures ALL of these problems.

“With LED backlighting, each individual pixel can be lit or unlit. There is no backlight lamp that lights the entire screen whether it's supposed to be black or not. So, with LED backlighting, black is literally BLACK. There is no light. It doesn't get any better than that, even with a CRT (since CRT's bleed light from bright areas to dark ones, which LED-lit LCD's don't).

“And because of the way LED's are by nature, there can be more precise control over the color of the backlighting, meaning better color accuracy throughout the screen. It also means no lamp replacements, and no dimming of the screen as the backlight bulb gets old.

“LED-backlit LCD's will render plasma sets completely obsolete within the next 3-5 years. They will be expensive at first and so probably won't totally replace cheaper projection sets for a while longer, but eventually, the only fight left is going to be between SED and LED-LCD. And SED technology is not quite there yet, so it's thoroughly possible that it will eventually be judged a "what's the point?" technology and lose out to LCD.

“LED-backlit LCD's are basically perfect sets. There's just not a lot about the technology that you can criticize or say "this technology does this well but not these other things, and this other technology does those other things well but not these things." There's just nothing you're left wanting from an LED LCD.” [Quoted from Jeff at engadget.com]

an alternative view at abelard.org

Having spent a large amount of time on and off for the last couple of years looking at LCD and plasma screens, I came to the conclusion that I wanted nothing to do with LCD screens. I have the impression that the LCD screen could not keep up with the movement (some people say that they cannot see this), and the picture was often harsh. I also came to the conclusion that with plasma screens, the movement was smoother and the picture better. However, my background reading also suggested that plasma screens were not yet as reliable as LCDs or CRTs [that’s your ‘ordinary’ television)]. The pixels on plasma screens are further apart than those on LCD screens, which is probably why there are very few small-scale plasma screens available at present - you have to be further away from the screen before the dots stop being intrusive.

Another issue is the power consumption. While the LCDs are generally pretty good and should improve as their technology advances, they are not much different from the best CRTs. For example, on checking a 32-inch LCD with CRT from the same high-end manufacturer, the consumption at 185 watts was virtually indentical.[1] Plasma screens, however, are often quite greedy, a 42-inch I checked at 360 watts. This is a difference of about 300 - 600 kilowatts over a year of 5-hour days, say £15 - 30 a year at 5p a unit (check your local price), not considering stand-by or often higher usage.

While very much liking the space-saving and lack of intrusion of these beautiful thin screens, I came to the conclusion that thin-screen technology was not really there yet, and that I would be wanting to replace any screen I got in another two or three years as the thin-screen technology inevitably advanced.

CRT is now a mature technology, and I remain uncomfortable with LCDs. Both LCDs and plasma I thought over-priced for the advantages. I prefer CRT pictures on the best sets to anything that LCDs have to offer, so, despite being a techo-junkie, I decided to settle for a flat-screen, letterbox, HD-ready CRT. This cost one-fifth or one-tenth of the price of the seriously tempting plasma screens, and I will keep the rest of the money working for the next two or three years until plasma, or even LCD or SED, technology becomes more impressive.

We are already using using LCD screens with computers - they are just so much easier to move around and give a nice, sharp image for most work; but we do maintain a CRT screen for colour checking.

end note

1. Much larger, back-projection displays can be obtained with a similar consumption level., but in my view the displays are invariably dull compared to the other technologies. See also comments on cost of replacement lamps at digital light projection and some other gadgetry.

related material
digital light projection and some other gadgetry

the web address for the article above is
https://www.abelard.org/news/science0606.php#led_backlit_140606

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“Some students are downloading a ring tone off the Internet that is too high-pitched to be heard by most adults. With it, high schoolers can receive text message alerts on their cell phones without the teacher knowing.”

The ring tone is based on a teenager-dispersal weapon trialed in a Wales shopping precinct.

“It was named the 'Mosquito' because the sound resembles that of a buzzing insect. And it works by emitting a harmless ultra sonic tone that generally can only be heard by people aged 25 and under. In trials, it has proven that the longer someone is exposed to the sound, the more annoying it becomes.” [Quoted from bbc.co.uk]

You can hear, or not, the sound here.
I can hear it still at 26.

Lead from yourish

all web sites will not be equal if the telecoms giants have their way

“Telecom and cable companies are in effect being allowed to erect toll booths along the information superhighway - and individuals who post their own videos or blogs online could find their websites confined to the internet's B-roads or even blocked altogether.

“Instead of an anarchic free-for-all that has dramatically broadened free speech and democratised access to information, the internet would come to be dominated by the giant internet and media companies that could afford to pay to make their content most easily available, campaigners say.”

comment by the auroran sunset

While I was writing this and reading and thinking more, my impression of what is going on has evolved. Thus, the earlier parts of my response are not entirely consistent with the later parts. However, I think it is helpful to leave it this way to show my working.

I consider it highly plausible that both the “congestion charging” and the “net neutrality” laws [see below] are aiming at the same anti-competitive objectives, and are in fact being pushed by the same group: the big telcos and the big content providers working in collusion.

congestion charging

The more I look at “congestion charging”, the more it looks like a ham-fisted attempt at legalising highway robbery, but it’s hard to be sure, because none of the commentators seem to be clear in their own minds as to what is being proposed.

An example that I have seen, supposedly suggested by some broadband provider or group of broadband providers, is that:

Yahoo could pay the provider to have their content load faster than Google’s content on the computers of subscribers to those broadband providers, or vice versa.

If correct, this is an attempt by ISPs to gain a second income stream from content providers (the ones writing websites, etc) with whom they currently have no contracts.

who pays who, and for what

Content providers already pay to make their content visible to the internet.
And they already pay in relation to how much bandwidth it takes to make them visible.

Content providers pay a hosting company for x amount of bandwidth/month at y price.
The hosting company pays a telco company for a line/pipe of a certain size (that can take a fixed amount of bandwidth), sufficient to provide the bandwidth required by their customers.

At the other end, people who want to look at the internet pay ISPs to give them a given level of access to the internet at a given price. Note that an ISP is a telco, or has a contract on a line/pipe with a telco, much as with a hosting company.

The telco companies have various contracts between each other saying, “I will let you send x amount of data through my network, if you allow me to send y amount of data through your network”.

In other words, telco companies already have bandwidth-dependent contracts, or implied contracts, with both the readers and the writers and between themselves.

‘threat’ to shake-down content providers

If I understand correctly, the telcos are now trying to force content providers who want to continue to be fully connected to their readers to, in effect, also take out extra contracts with every other ISP.

The telcos are trying to force content providers to pay multiple times again for what they have already paid. [see below]

And this would probably be in rolling auction fashion. After all, if Yahoo pays to have their content downloaded faster than Google’s, Google then has to pay more or get cut out the market, then Yahoo has to do the same, round and round.

Meanwhile, the small customers can neither afford these spiralling costs, nor afford to get injunctions and the like. At present, any large hosting company has contracts with multiple telcos for lines/pipes, so that if one telco goes down or tries to play games, the service does not fail.

The smaller cheaper hosting companies often cannot afford this precaution, thus this is another layer of protection that the smaller content providers are excluded by price.

but they would need a telco cartel

However, this “congestion charging” racket does not seem remotely practical. At abelard.org, we have a contract with a hosting company. Are we expected to make separate contracts with hundreds of different ISPs and telcos?

The only way I can see the scheme working is with some sort of telco cartel. The cartel then forces the extra cost onto the hosting companies, who we and everyone else pays. The cartel then distributes the windfall amongst the cartel conspirators.

Is this what the telcos are actually aiming at? This is at a time when technology is making it cheaper and easier for new telcos and ISPs to set themselves up. This ‘proposal’ looks more like desperation, than a serious threat.

net neutrality

Then there is the “net neutrality” bill, being pushed in the US by some of the biggest content providers around as a way to stop the ‘threat’ of “congestion charging”. Here is a copy of the bill [.pdf file].

The “net neutrality” bill has one small part that deals with the above piracy ‘threat’:

“IN GENERAL. - A network operator [isp/telco] shall - [...] (3) not assess a charge to any application or service provider not on the network of such operator for the delivery of traffic to any subscriber to the nework of such operator”

The bill also has a couple of other parts which sound reasonable, but seem pointless, as any ISP breaking those conditions would make themselves unattractive to their customers (assuming no cartel).

However, there is a lot more in that bill, and large amounts of it look suspiciously like attempts to tie smaller competitors in anti-competitive red-tape. And this appears to be to what the opposition is objecting.

is this how they plan to make that cartel?

So the so-called “neutrality” bill also appears anti-competitive. The strange part is that, although the bill is being pushed by big content providers, the red-tape is applied to the ISPs/telcos.

In other words, the bill would likely have the effect of making it easier/possible to form a telco cartel, by once more increasing the costs on smaller ISPs - costs that are currently falling due to technological advance and competition.

Now a telco cartel means higher bandwidth costs. That in turn means cutting the smaller content providers out of the market. and we’re back to the same result as the “congestion charging” proposal:

• a telco cartel able to charge what it likes, a return to the old days of expensive telephone calls.

and

• the smaller content providers would be priced out of the market, so that only the likes of Google, Amazon, Microsoft, Yahoo, etc are left.

good cop, bad cop

This looks suspiciously like good cop/bad cop, both trying to get the same result.

On one side the telco giants are pushing “congestion charging”, a scheme that is outrageous, but almost certainly totally impractical. I do not believe ‘they’ have any interest in this scheme other than as an excuse to push “net neutrality”.

On the other side, Google, Amazon, Microsoft, Yahoo, etc are pushing to ‘protect’ us with a “net neutrality” bill that raises the costs for ISPs, thus making the telcos’ outrageous scheme suddenly more plausible.

This Slate article seems rational, but is weak on the practicality or impracticality of the various schemes. It has useful background ideas.

“In trying to figure out who's right, let's forget about the Internet and look at KFC. The fast-food chain discriminates. It has an exclusive deal with Pepsi, and that seems fine to pretty much everyone. Now, let's think about the nation's highways. How would you feel if I-95 announced an exclusive deal with General Motors to provide a special "rush-hour" lane for GM cars only? That seems intuitively wrong. But what, if anything, is the difference between KFC and I-95? And which is a better model for the Internet? [...]

“A broadband company already has incentives to make the network neutral, because it's a better network that way. If AT&T makes money on an exclusive deal, they'll lose it somewhere else. Whatever money AT&T earns by prioritizing Google rather than Yahoo!, it will lose by making its product - broadband service - less attractive to consumers.”

email email_abelard [at] abelard.org

© abelard, 2006, 12 june


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