At Lightfair next week, Renaissance Lighting will showcase a number of LED luminaires, but the demonstration of a new liquid-phosphor approach to SSL, that's not yet in a shipping product, may garner more interest. Renaissance CEO Barry Weinbaum states, "This will allow us to get up to 100 lm/W out of the fixture."
Renaissance claims a number of advantages in efficiency, color temperature and CRI for what is somewhat similar to a remote-phosphor implementation. About the phosphor, Weinbaum states, "It tunes the light to whatever color temperature we want to get to." Actually the phosphor produces the desired color temperature based on chemical formulation, and a choice of formulations will enable a choice in color temperatures. About the phosphor and CRI, Weinbaum states, "It gives a CRI so high that it's the equivalent of a Tungsten light." Weinbaum claims the CRI will approach 100.
Remember that these claims are for now just company statements about a planned demonstration and not about a shipping product. Expect first-hand reports next week as to how well the demonstration luminaire performs. But the efficiency claims are impressive. Weinbaum points out that typical luminaires are 50 to 60% efficient meaning the rest of the light produced by the LED source is wasted. He states, "This approach will demonstrate a lighting efficiency of 80 to 90% and beyond."
Renaissance is using a liquid phosphor that is supplied by NNCrystal US Corporation. A hollow glass optic located between the LED source and the lens contains the phosphor. For now, Renaissance isn't revealing details about the chemical makeup of the phosphor.
Renaissance will combine the phosphor technology with its previously announced Constructive Occlusion technology in the demonstration downlight. Weinbaum also believes that the clear phosphor yields a more attractive luminaire when the light is turned off noting that many remote-phosphor approaches have a yellow hue.
Weinbaum claims Renaissance is taking a different tact than most luminaire makers in pushing efficiency. He note that others are using the latest high-brightness LEDs, and mixing wavelengths to balance lumen output and color temperature. Weinbaum, states, "The technical approach is something that we are defining as phosphor centric." He claims that the liquid-phosphor approach won't require Renaissance to use the highest-brightness LEDs. The implication is that Renaissance could use lower-power, less-expensive alternatives.