From Humble Beginnings to Total Domination, LED is Growing Up
Fluorescent, halogen, metal halide – what are these? In case you didn’t get the memo, there are no more choices of light source; it’s all LED now – light-emitting diode. Halogen has been disappearing from the market for a while, and now even most fluorescent and compact fluorescent (CFL) lamps are being phased out by manufacturers and energy efficiency legislation. In some ways, lighting has become simpler because there is only LED; however, LED can take so many forms that a whole new world of light has been opened up to us. LED is allowing designers to use light the way architects have always wanted to – as lines, planes, dots, surfaces, colours, changeable, invisible, you name it, and some manufacturer is either researching or developing it or will customize it to create the effect you are seeking.
No one ever imagined that LEDs would completely replace all other means of lighting our built environment, but their energy efficiency has catapulted them to the top of the market. They use a fraction of the wattage of other sources and can produce myriad choices in colour, output and shape. They produce less heat than other lamps (too little to affect the cooling load in buildings the way older lamps did); they lack the ultraviolet and infrared light components that may be harmful to artifacts, goods and people; and they are longer-lasting than other sources.
It took a little while for LEDs to really hit their stride. Producing enough usable white light from a diode took some ingenuity and many trials. Then came the problem of “driving” the LEDs with practical equipment that would fit into fixtures and ceilings and be compatible with line voltage, dimmers and the electrical infrastructure we have all become accustomed to.
LEDs first entered the market in the early 1960s, at first using only infrared light in remote-control devices for consumer electronics. We all had a digital clock that used the first visible light LED, which was red. Soon, other colours were produced by varying the chemical elements in the diode; however, they were very dim in the early experiments and were set aside. Over the years, through further experimentation, scientists discovered that white light could be produced by mixing red, blue and green, but again, the quality and quantity of light was poor and not well-suited to architectural lighting. The ability to produce violet LED light, allowing the creation of a full spectrum white light, was not developed until 1994 by Nichia Corp. Shuji Nakamura, co-winner of the 2014 Nobel Prize in Physics, spoke at Light Fair in New York the following spring (writer in attendance) to expand on how the improved quality of white LED light could impact the lighting industry.
Even in 2015, at the Light Fair (the largest annual conference on lighting in the world), LED was still fighting to dominate the tradeshow floor. Among the many garish, glary, cool white LED lamp retrofit makers, there were a few memorable fixture manufacturers whose designers had come up with uniquely integral LED fixtures – fixtures that have departed from lamp-based technology and have embraced the inherent qualities of LED to form light rather than receptacles for housing a light bulb. A Canadian company, Fluxwerx, was among my game-changing favourites, with their View fixture that resembled an I-beam, with light emanating from the web of the beam. They didn’t even have a booth of their own; instead they had one fixture hanging in someone else’s booth.
Since about 2010, we had been specifying Vario Flex, a linear fixture produced by a German company, LED Linear, that is completely encased in polyurethane, allowing a flexible waterproof small-profile milky white strip of light that can be used almost anywhere with low-voltage wiring.
In September, I had the opportunity to visit the headquarters of an Italian manufacturer, iGuzzini (partnered with Sistemalux from Canada), where quality of light and miniaturization of the package are their main concerns. They have designed recessed downlights (the Laser Blade) that are as small as 1” x 2 ½” x 2” deep and use 6 watts of electricity to produce 400 lumens of light. Phillips and others are making surface-mounted downlights that are only 5/8” deep and mount to a standard junction box.
The minimal size, fluidity of shape and the benefit of control technology have been nothing less than revolutionary in the lighting industry. The examples mentioned above are just a few of the many new products being developed using LED in innovative ways. Architects and designers now have the ability to design with light, using it to sculpt space, improve well-being and create natural ethereal effects.
Control of light fixtures has also developed with the Internet of Things (IoT) to make each light fixture “smart” by embedding connectivity to each fixture, allowing users to control them individually. This holds the potential to change the way our buildings and homes may get wired in the future. Instead of using 120-volt, 12- or 14-gauge wire to each fixture, buildings may be completely fed by IT contractors using low-voltage wire, freeing us from high-voltage safety issues as well. White light can have a tunable colour temperature, adapting to the time of day, the activity taking place and our circadian rhythm, changing from bright white for energizing activities to warm, dim light for a romantic dinner.
The rate of change is pretty staggering in an industry that tends to move more slowly than some, but it’s a welcome change for designers. Architects have always been enthralled by how light interacts with their designs. LED is allowing us to manipulate light with less of the usual encumbrances or awkwardness of fixture housings.
Research and development is moving so quickly that LED is now the only type of lighting that most manufacturers are thinking about. Our kids will talk about light bulbs in the same way we talk about rotary telephones and manual typewriters.