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Some LED Lights Spark Concern Over Toxins

February 21, 2011 Category :Commercial Lighting 0

Because it’s energy-efficient, LED lighting is spreading into new areas, but an academic study cautions that some types of LED lights use hazardous metals.

The University of California at Irvine last week published results of a study into the materials used for LEDs in Christmas tree lights and car brake lights and headlights. After crushing these types of lights, researchers measured the contents and found they contained varying amounts of toxic materials, including lead and arsenic.

“What our study showed clearly was that some LED lights qualify as hazardous waste, depending on color and light intensity, according to federal (US EPA) regulations, and State (California) regulations. The red, low intensity fixtures that we tested exceeded lead (Pb) standards for California regulation by about 8 times, and exceed the federal regulations by about 35 times,” said Oladele Ogunseitan, chair of UC Irvine’s Department of Population Health & Disease Prevention via e-mail.

Right now, these products are not classified as hazardous waste, but Ogunseitan recommended that people dispatched to clean up vehicle collisions use protective gear. Homeowners should also wear gloves and masks in the case of clean-up. The copper used in some LEDs can pose health hazards to river and lake ecosystems as well if disposed of in a landfill.

Ogunseitan said that the move to LED lighting is a case in which there should be mandatory product replacement testing. He claims that the potential environmental health impacts were not sufficiently tested before manufacturers put them in products as a replacement for incandescent bulbs.

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The Truth About LED

February 21, 2011 Category :Commercial Lighting 0

There are 3 types of LED TVs:

Edge Lit Screens: These have LED lights placed around the rim of the screen. This is done using a special type of diffusion panel which spreads light evenly behind the screen. It is also the most common type of LED screen, and is the thinnest of the three.
Dynamic RGB LED Lights: These are positioned behind the screen instead and allow dimming to occur in locally specific areas of darkness on the screen. This allows the TV to present better black and white levels at pretty high dynamic contrast ratios. The only disadvantage of this is that small bright objects with dark backgrounds are shown in less detail.
Full Array of LED Lights:These are arranged behind the screen but cannot be dimmed or brightened individually. This type of screen has a lot of advantages as these TVs save more power, have better brightness and contrast, as well as better response time and colour reproduction. This is definitely the best of the lot, but TVs using this technology are generally more expensive.

LED vs LCD
LCD has been around for quite a while now, as the technology first got popular when it started being used in digital watches. It basically uses liquid crystals between plates, and these crystals change when current is applied to them. Of course, colour LCD screens have only been introduced relatively recently, but the technology behind it is more or less the same. The disadvantage of LCD screens have relatively poor contrast level and respond slower to fast moving images, creating a motion blur.

LED, on the other hand has been gaining momentum over LCD in recent times. Not only do they perform better than LCD TVs, but are also more reliable. Earlier, LED-backlit TVs were really expensive, but the technology has gained in popularity, allowing prices to be reduced quite drastically. Even smaller manufacturers have launched LED-lit TVs, although all of them aren’t very impressive. But some LED-lit TVs like the LG Infinia 55LX9500 are complete winners in my eyes as it has brilliant contrast, colour reproduction, great black levels and looks gorgeous.
There is one argument about the price of LED-lit screens that is quite valid, though. A lot of other devices such as laptops and netbooks use LED-lit screens, which doesn’t really affect the price. So why are LED-lit TVs so expensive? Many manufacturers don’t produce the screens themselves, and outsource them instead, and some argue that they are less readily available than LCD screens. Obviously this increases demand, which gives rise to steeper prices. But like I said before, the prices are coming down gradually, and since LED-lit TVs have so many advantages over LCD TVs, the right to make them a little more expensive is justified.

In my opinion, buying an LED-lit TV is the right choice. I’ve already outlined the advantages, and it’s pretty simple – if you have the money, buy an LED-lit TV. It will give you a better viewing experience, will last longer and reduce your carbon footprint, even if only by a little.

Taking the technology further
The next step is OLED (organic light emitting diode) screens, and these are even better than regular LED screens. The difference here is that OLEDs emit their own light in the form of electroluminescence. These screens are even brighter, sharper, have better response time, colour reproduction and contrast levels as well as wider viewing angles. But this is still a work in progress, and although plenty of manufacturers have outdone themselves with brilliant prototypes as well as professional purposes, they are yet to be launched for consumer use.

By now, you would have probably realised that LED-lit TVs are definitely superior to LCD TVs. Sure, they cost more, but you can’t really put a price tag on happiness right? And that happiness is what you will feel while watching your favourite movie.

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