April 14, 2012 at 9:43 AM ET
Ever since the LED TV was introduced 2009, TV makers promoted and advertised it as a new technology. They do appear different than plasmas or LCD HDTVs. The cabinets are far thinner and the pictures are brighter, especially when in the dealer showroom picture setting. But this year, LG and Samsung will also be introducing the first large screen OLED TVs. Why would anyone want one if they already own an “LED” TV? Isn’t it the same, except for the letter “O”? Read on for the answer.
In a word: No.
LED TVs are simply LCD TVs that use a different type of lamp made from light emitting diodes, in place of a fluorescent lamp (typically called CCFLs) for illuminating the picture. LCDs are screens of colored pixels. They do not create light, and as such, they require a light source. (Plasmas and the old style CRTs don't need lamps, because the phosphors that make up their screens emit light and color when zapped with electricity.)
The 2009 Samsung ad above reads, “A Whole New Species of TV”. This was quite inconsistent for the TV industry, as it was first time a television maker referred to the technology by the type of light bulbs used. Less expensive LCDs were never called "CCFL TVs" -- prior to or after the debut of "LED TV."
With LCDs, the CCFL lamps are always placed directly behind the panel, which adds to the thickness. LED lamps are placed on around the panel beneath the screen bezel (2012 ES Samsung, LG and Toshiba LED models and many other brands) or like CCFLs, behind the LCD panel (select LGs, Sonys, Vizios, Sharps and EH Series Samsungs).
The TV makers claim the LED models provide better contrast. The claim is aided by the TV makers designing the LED lamps to shut off completely when the content fades to black. Some LED TVs can shut off a region of the LED lamps, depending on which portion of the image is black at any given time.
Power consumption is lower in LED TVs compared to CCFL bulb equipped LCDs, making LED sets more energy efficient. However, it's worth noting that the difference in power consumption is unlikely to make up for the higher cost of the larger LED models over a comparable, lower priced CCFL LCD over the products lifetime.
Meanwhile, OLED really is a whole new large-screen technology. The flat panel is made up of millions of tiny LEDs. The “O” in OLED stands for “organic” which means there is carbon within the molecules of the emissive (light producing) layer of the panel. Large-screen OLED panels need no lamps -- they are self illuminating. OLED HDTVs can be thinner and lighter than the skinniest LED LCDs, and have several other advantages over LCD TVs, regardless of whether the LCD is lit by LED or CCFL.
For instance, they provide very wide and consistent color no matter where you are seated in the room. LED LCDs tend to get significantly dimmer as you move away from the center, and many exhibit color shift. (There is one exception that I have found, the new WT50 Panasonic, which I reviewed here on HD Guru.)
OLEDs are quite energy efficient, besting all other flat panels in low power consumption. But since the expected cost of the first models is at least $8,000, you’ll definitely never realize a savings at first-generation prices. They do make very bright images that should “pop” against the other flat panels at TV stores. The 55-inch OLEDs shown at the 2012 attracted attendees like moths to a light bulb on a summer night.
The greatest attribute of OLED is the ability to have the deepest blacks of any flat panel technology. Unlike LED backlighting, which at best can only dim the LCD image in regions, OLEDs can produce a very low luminescence level down the individual pixel. This ability coupled with bright whites is why OLEDs are expected to have the highest contrast. OLEDs are very fast devices, changing intensity faster the best plasmas and the fastest (240 Hz) LED LCDs. This means there's no risk of motion blur.
OLEDs can make more colors than CCFL or LED panels. While impressive, this may not translate to a significant asset, since HDTV itself is limited to a specific color palette, one that a number of plasmas and LED HDTV already can meet or exceed.
In just a few months we expect the first large screen OLED HDTVs to be offered for sale in the US. LG is expected to be in the 55-Inch size class while the Samsung is now rumored to be a 65-Inch screen. We’ll see how many LED TV owners are surprised to learn their sets are not same technology or capable of the same performance when this truly new big screen technology arrives. Fortunately, if you read this article, you won't be among them.
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