Soraa Chief Technology Officer Mike Krames recently ressponded to LED Magazine article's claims that the company's GanN-on-GaN MR16 emits large quantities of UV rays. Below is Krames blog entry on the company website:
With the introduction of any new, transformative technology comes the inevitable backlash from incumbents. This was readily apparent in a recent LEDs Magazine article, “LEDs ready to displace halogen in MR16 lamps”. But here I’m not talking about halogen, but rather incumbent blue-based “GaN-on-X” LEDs (where X = any foreign substrate, e.g., sapphire or silicon carbide) the authors espoused as finally able to meet the difficult requirements to be a true replacement lamp for the halogen MR16 - requirements Soraa lamps met more than a year ago.
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| Soraa CTO Mike Krame. (LEDinside/ Soraa) |
At Soraa we have harnessed the power of GaN-on-GaN in a holistic design approach to MR16 lamps which provide up to 65 Watt equivalent, single-beam intensity, full visible spectrum performance including CRI and R9 (deep red) rendering levels of 95, true halogen-like whiteness rendering (not possible with blue-based LEDs), and enclosed-fixture use, in products rated for > 25,000 hrs and warrantied for three years. This is possible because, just as GaN-on-GaN has advanced over GaN-on-X LED technology, silicone and phosphor materials technologies from our partner vendors are pushing to the next level, beyond the limited performance requirements of GaN-on-X LEDs.By comparing the best available GaN-on-X LED technology in (non-ANSI) laboratory MR16 designs to early prototypes of GaN-on-GaN MR16s, they hoped to convince their readers that the former is finally ready for this application while raising a reliability scare regarding the latter. While admitting that GaN-on-GaN technology provides higher quality LED material and higher efficiencies at the high current density operation required for applications like MR16 retrofits, it is quite telling that they spend the bulk of their effort trying to debunk this obviously superior technology. Such are the first gasps that precede the inevitable death throes of a technology that just couldn’t win.
Contrary to the authors’ suggestions, Soraa’s GaN-on-GaN products emit essentially no ultraviolet (UV) light (less than 0.1% of the emission is less than 400 nm), and in fact provide a better match to halogen’s emission spectrum throughout the visible light regime than any other available lighting technology. The high intensity at 440-460 nm typical for blue-based GaN-on-X LEDs, on the other hand, may not be something to be so proud of. The fundamental color rendering challenges of broken-spectrum blue-based white LEDs are well documented, and while the color rendering index (CRI) of blue-based LEDs can be gamed to achieve 90 or more, errors in hue shift are apparent when looking at large color sets (e.g., R9, etc.). Furthermore, the lack of violet emission means blue-based LEDs cannot excite Optical Brightening Agents (OBAs) in white or bright-colored clothing, cosmetics, plastics, etc. Unlike almost every other artificial light source (fluorescent, high-intensity discharge, etc.) developed over the last century, blue-based LEDs completely missed the mark here.
Incumbent technologies always fight back against the newer, better approaches - it’s just the natural gasping for breath that portends demise. We’ve seen this pattern time and again in history, from vacuum tubes to transistors, from CRT tubes to LCD TV, and now from GaN-on-X LEDs to GaN-on-GaN.
