Illumination ruminations

Alix Paultre, Editorial Director, PSD



The ability to create light is one of the definitive things that we do that separates us from the other animals on this planet. Fire, our first great technical discovery (or a really neat gift from a Greek God with a cool name), gave us two very powerful things that are still central to us: heat and light. The heat enabled us to cook food and reduce the need for massive teeth and jaws, paving the way for the human face and speech; the light freed us from the brutal timekeeping of the sun, extending our active lives far into the darkness.

Needless to say, it would be hard to cook without light, and campfire light was quickly replaced by animal tallow lamps. These first luminaires were displaced in their turn by better fuel-based lamps, candles, and eventually the electric light.

The funny thing about the incandescent lamp is that is is not much more advanced than our progenitor’s campfire. Many forget that a traditional light bulb is merely a very tiny campfire we managed to contain in a vacuum tube, cooking heat and all.

The reason the thermal issues of incandescent light never really became an issue in lamp design is that it replaced legacy systems that were even more inefficient, so the existing support infrastructure could handle the thermal load. Edison not only designed his bulb to fit the existing candle sconces of the day for easy retrofit; he also knew that those old candelabras could handle the heat from his new bulbs.

As we move into the new and rapidly-expanding world of solid-state lighting, that very legacy infrastructure is now hampering development as the industry literally works to fill the hole left by light bulbs. Incandescent luminaires have very, very different design requirements for light distribution, power, and thermal management, yet most of the lighting industry is focused on cramming some extremely complex circuitry in a cramped little hole.

Sadly, there is no other choice. Market inertia alone guarantees that there will be an Edison socket in many lamps for the foreseeable future, my only hope is that we at least stop creating new Edison-based luminaires and eventually focus on only making application- and performance-specific lamp designs that completely exploit the abilities and functionalities of LEDs and other solid-state lighting sources.

The biggest issue at this time is one of education as we migrate between the two worlds, that of the burning-light past and the diode-, EL-, and OLED-based solid-state lighting future. First we must continue to educate the design engineering community about how to drive and manage these next-generation illuminators, and create standards for the industry so everyone can have equivalent expectations on performance and operation. We also must educate the consumer, industry, business, and consumer, on the benefits and advantages of this new technology.

Unfortunately , it is harder to sell a marketplace on a new tech when it has to struggle so mightily to look and work like the old tech.