If someone were to offer you a 'footlong,' you might reach wide-eyed and open-mouthed for the mustard. A 'footlong,' in American speak, is a hotdog that measures, yes, 12 inches. To the non-purists, the term also denotes a hoagie* of the same jaw-dropping dimensions.
And now, it could also describe one of the latest breakthroughs in organic light-emitting diodes, as South Korea's LG Chem has begun making and marketing what it claims to be the 'world's largest' commercially available OLED panel, measuring 320 millimetres long by 320 millimetres wide. For fans of inches: that's 12.6-by-12.6, or a little over a foot in both dimensions. It's thin too, at 0.88 mm, or 0.03 inches.
As a reminder, OLEDs are the would-be next big thing in lighting since, well, LEDs. OLEDs are typically patches of material that emit light when an electric current hits them. Proponents have long said they will revolutionise lighting and design because they can be built not only into the fabric of luminaires, but also into furniture, walls, buildings, bridges, clothing, car interiors, you name it. In some forms they will bend. They are meant to liberate lighting from the bulb form factor.
But manufacturers have struggled to bring down their costs, and to match the performance of LEDs, which are rudimentary semiconductors built into bulb form and requiring a mere 20 percent or less of the energy of conventional incandescent bulbs. OLEDs are only about half as efficient as LEDs.
The new square-foot OLED panel from LG Chem doesn't break any new ground in that regard. It has an efficiency rating of 60 lumens per watt (lm/W). LEDs these days are around 100 lm/W.
And judging by the price, LG Chem hasn't smashed any cost barriers. The company is selling the panels for $680 each. But don't be put off; if you really really like it and all of its 320 square millimetres, the company said in a press release that it will offer 'a lower negotiated price for bulk orders.'
The announcement fell short of LG Chem's promise last September to deliver an OLED panel by November that would match LED efficiency. Lux asked LG in December for an update on that product; we have yet to hear back.
That aside, the company did announce another new panel. In addition to the square-foot model, it said has 'completed development' of a flexible plastic version that bends a lot more than LG Chem's typically thin glass OLED models (the 320 x 320 appears to be glass). LG Chem rated the efficiency at 60 lm/W - again, well below LED territory. It priced engineering samples at $250 per panel and anticipates beginning mass production in July.
Both new models come with some impressive specs. The foot-square model has a 'nominal' lumen output of 800 – roughly equivalent to an old 60-watt incandesent – and can hit 1200 lumens, LG Chem said. It also has a colour rendering index (CRI) of 90, which puts it above LEDs (typically rated around 80) in its ability to show true colours (but still below incandescent's 100 CRI). It has a colour temperature of 3000K which is fairly close, but not quite as good as old incandescents.
The plastic model weighs in at 75 lumens, a CRI of 85, and 3000K.
LG Chem says it now offers nine different OLED panels (see more on LG Chem's OLED webpage. But with the latest offering going for close to $700, and with efficiency still well below LEDs', it will probably still be a while before any one's going to make a big meal out of them.
*A hoagie, in case you need a primer, is the same thing as a 'submarine' (sub), a 'grinder,' a 'hero,' or a 'wedge' – a sandwich stuffed with seemingly every imaginable lunch meat and lettuce on one of those long, narrow slabs of bread of the sort the French call a baguette. The name varies with regions of the US.
Photo is from LG Chem
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