More than one year after Soraa demonstrated it (see my blog from 5/6/13), the importance of whiteness rendering is now being noticed by the larger lighting manufacturers. Perhaps the most notable imitation, from Philips (see LEDs Magazine July/Aug 2014, pp. 9-10), mixes in some violet-emitting with blue-emitting LEDs to provide a level of Optical Brightening […]
Shining more light
Most of us learned in school that we do not actually “see” objects around us, but instead the light reflected by the objects. While the reflective properties of the objects are important in determining their perceived color, equally important is the light source illuminating the objects. A recent article on CNET, “Shining a light on […]
Top Ten Myths of LEDs: #5 – “LEDs color-shift with time”
In the early days of white-emitting LEDs, the available chip packaging materials were ones developed decades earlier for use with red- and green-emitting devices. Unfortunately, when using those materials for blue-based white LEDs (blue LED + phosphors), unexpected problems arose. The epoxy resins typically used as the lens encapsulation for the LED chip were photosensitive […]
Top Ten Myths of LEDs: #6 – “LEDs can’t run hot”
Standard incandescent lamps convert almost all the power they consume into radiation (basically, heat). Unfortunately, only about 5% of this emission is in the visible spectrum, making them very inefficient light sources. On the other hand, since almost all the power is radiated away, there is little need for thermal management. LEDs put 100% of […]
Top Ten Myths of LEDs: #7 – “LEDs have high glare”
I’m standing in the taxi queue at Chicago’s O’Hare airport, having to squint ahead to gauge my wait. The cause of my discomfort: a horrible, blue-LED array-based outdoor luminaire ahead of me and above, spilling light in all directions and casting a putrid smear of yellow-green color against a nearby wall of the terminal, and […]
Top Ten Myths of LEDs: #8 – “LEDs are best left to China”
I have been in the LED business for almost twenty years, and each year I hear a comment along the lines of “LEDs are a commodity product”. What’s the definition of a commodity product? It’s one that is very cheap, undifferentiated, anybody can make it, and margins are low. And each year, I look at […]
Top Ten Myths of LEDs: #9 – “LEDs are expensive”
“Ten bucks for a light bulb?!”, exclaims my daughter in response to my estimate of the ‘tipping point’ price for LED-based lighting products for the residential consumer. She, like many consumers, has yet to internalize that the real cost of ‘inexpensive’ conventional light bulbs is energy consumption, and that LEDs pay back on this aspect […]
Top Ten Myths of LEDs: #10 – “LEDs are dangerous”
Any time a new, disruptive technology enters the public sphere, concern is raised about almost every conceivable aspect. This is especially the case for lighting wherein each and every one of us has a base of experience and, likely, some opinions. While it is certainly prudent to scrutinize any new technology from a health and […]
