LG Electronics just unveiled its 55-inch ‘OLED’ TV at CES. I put OLED in quotes because it’s not the OLED we know. Most of us have expe­ri­enced OLED through Samsung’s Galaxy line of smart­phones. Regardless of RGB-stripe or PenTile Matrix the OLEDs work in the same way: they emit both light and color. A red OLED phos­phor emits red light when elec­trons are pumped through it. Same goes for green and blue. This is exactly what you see on this type of OLED dis­play. WOLED is different.

WOLED stands for White OLED. Each pixel is made up of red, green, blue OLED sub-pixels to gen­er­ate a white pixel. I am uncer­tain whether those sub-pixels are tuned sep­a­rately, but I’m guess­ing not. Before I was won­der­ing what LG Display meant by ver­ti­cal accu­mu­la­tion. I think I know now: The three OLED diodes are stacked ver­ti­cally, not side by side like a typ­i­cal OLED dis­play. The red, green, and blue light out­put is ver­ti­cally mixed to gen­er­ate white light. Because the three OLED diodes are ver­ti­cally arranged each pixel should be small enough to pack 1920×1080 or more on a 55-inch sized dis­play. Brightness is prob­a­bly con­trolled at the pixel level. So think of WOLED as the ulti­mate local dim­ming back­light with pixel-level bright­ness con­trol. Next, color.

A WOLED dis­play gen­er­ates color by using a color fil­ter. The down­side of using a color fil­ter is light absorp­tion of about 70% on a typ­i­cal LCD. LGE’s announce­ment men­tions “4-Color Pixels” and I believe that’s code for RGBW. This is not imple­mented at the OLED level but only at the color fil­ter level. The white is absolutely nec­es­sary because a 55-inch WOLED TV will require a tremen­dous amount of power to gen­er­ate enough bright­ness that is equiv­a­lent to a 55-inch LCD TV. The white por­tion of the color fil­ter, which does not absorb any light at all, will help to brighten up the WOLED dis­play while reduc­ing power con­sump­tion. RGBW imple­mented on a LCD panel would result in washed out col­ors because there is no way to com­pletely shut off the white sub-pixel, but with the pixel-level bright­ness con­trol on a WOLED the white por­tion of the color fil­ter can be com­pletely turned off mak­ing blacks com­pletely black.

LG Display has pushed the con­cept of the local dim­ming LED back­light to its the­o­ret­i­cal max­i­mum. Using OLED tech­nol­ogy bright­ness is con­trolled at pixel level. Vertically stack­ing the OLED diodes mit­i­gates the prob­lems asso­ci­ated with dif­fer­en­tial aging. And by using a RGBW color fil­ter power con­sump­tion is low­ered. The 55-inch OLED TV by LGE does not use exactly the same OLED tech­nol­ogy we are used to, but with WOLED we get extremely thin dis­plays, absolutely black blacks, and superb con­trast. But there are just three lin­ger­ing questions.

First, power. RGBW reduces power con­sump­tion, but how much power will a 55-inch WOLED TV con­sume? Second, how long will WOLEDs last? Third, what’s the price?