Greener BeeGreen GadgetsOLED, explained: Incredible tech, but what about cost and content?

Recently, I took a deep dive into the world of high dynamic range (HDR), because it’s a curious new trend in TV technology—as in, equal parts mesmerizing and confusing. There’s a learning curve to understand what HDR offers, especially since the difference doesn’t always pop in fluorescent-lit showrooms. At the same time, HDR-10 sets are starting to become affordable, and what’s sometimes hard to appreciate at a big-box retailer can look quite stunning in your own home.

In many ways, the same can be said about the other major TV standard that we’re seeing more lately: OLED, which stands for organic light emitting diode. It’s being called the future of TV tech, promising deeper blacks, less motion blur, and sexier colors.

Conveniently, OLED screens are also coming down in price. “Affordable” isn’t the right word, but we’re getting there, with the $9,000 55-inch sets of 2013 being succeeded by models as cheap as $2,300 (along with larger screen options for more cash). Some have 3D, others have curved panels, and all of this year’s models have support for HDR modes and 4K resolutions.

So today, we’re continuing to break down the modern screen landscape by breaking down OLED: how does it work and do the technology’s advertised claims hold up? Along with some answers, we also have details about how manufacturers and content producers fit into the current OLED picture.

The blacker the pixel…

You may see the acronym OLED and think you’re not getting anything much different from LED panels already on the market. What is “organic” LED? Is this like shopping for eggs? Should we make a “free range LED” joke?

The short answer: the word “organic” gets to the heart of the OLED difference. It explains how its image-generation differs from the competition.

Consider LED screens, which are themselves something of a misnomer. When you hear about an LED screen, it’s actually an LCD (liquid crystal display) screen but with improved back-lighting technology called LED. In modern LCD screens, liquid crystals are activated by electricity to rotate and allow light to come through each tiny square of the image (or pixel). Light shines through red, blue, and green filters, and these mixes combine for every color in the spectrum from dark to white. If all panels are rotated in such a way, they let no light through for any of the three colors, resulting in “black.”

While this crystal-rotation trick has tons of benefits (cheap price, thin, light materials), LCD screens have their drawbacks, the obvious one being black level. Even if an LCD screen’s crystals are rotated in such a way as to block all color information (and create a “black” pixel), they’re still backlit by a panel. This will always result in a “light bleed” effect that projectors and antiquated CRT screens don’t have to contend with.

An LED version of an LCD screen mostly works the same way, but it uses a superior type of bright back panel. We could get into the weeds about back panels (LED vs. CCFL), but the major difference is that LED panels can drive images that are simultaneously brighter and darker to deliver a greater contrast ratio. Newer LED TVs have what’s known as a “full array” of smaller LED panels, which can be individually dimmed by the TV itself. If a portion of the current scene in a film, show, or game is dark, that portion’s backlight can be dimmed to reduce the amount of light bleed coming through. This will dramatically improve the visible contrast ratio (meaning, how well black sits next to white in an image), but it’s still not a pure black value. Light remains, however dim, behind the liquid crystals.


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