Cree Introduces 200 Lumen/Watt Production Power LEDs
ndverdo writes "Cree just announced production power LEDs reaching 200 lumen/watt. Approximately doubling the previous peak LED light efficiency, the new LEDs will require less cooling. This should enable the MK-R series to finally provide direct no-hassle replacements to popular form-factors such as MR-16 spots and incandescent lighting in general. The LEDs are sampling and it is stated that 'production quantities are available with standard lead times.'"
While it indeed is a commercial product, it's also a new industry milestone.
While I *do* love to hear stories like this, and I believe that LED lighting, in some form, is the future, it dissappoints me to see that so-called "white" LEDs still produce quite poor spectra. Check out the spectrum on page 4 of the datasheet given on the MK-R series page. Compare this to the sun's spectrum. Because these are phosphor-based LEDs, you get a relatively narrow blue-violet peak (the true colour of the LED), followed by a wider hump, peaking at about yellow (the broad emission spectrum of the phosphor coating, which is down-converting those blue photons). While this looks "pure white" when you look directly at the beam, it renders colours very poorly (i.e. the reflected light from objects looks the wrong colour). This is what causes LEDs and fluorescent lights to often make a room appear sickly and food look unappetizing. Ideally, we should strive for a light which closely emulates the sun's spectrum, but this is obviously challenging.
Fortunately, there are a few next-gen LED technologies on the horizon. Quantum dot-based LEDs seem promising. By making dots of a specific size, you can precisely tune the output wavelength of a QD LED. Presumably you can combine a whole bunch of QD LEDs, each tuned to a different wavelength, to approximate the sun's spectrum. Alternatively, certain types of organic LEDs offer the ability to tune the wavelength, and similarly, produce a composite device which has a more ideal spectrum.
Still, until these materialise, plain 'ol incandescents are the only cheap light sources which produce a nice, continuous blackbody spectrum. Sigh.
CFL's rarely last more than 10 months. If they do they are at half the brightness of a ten year old bulb.
Let me guess: You also pay $6 for eight of them...
No sig today...