About Modern Lighting
Modern lighting is not as simple as the light bulb of the past. Previously light bulbs tended come in one spectrum. This was based on the material of filament, how much power was put into it, or what gas filled it. With the advent of LEDs we were exposed to a wide range of specific spectrums. Now you are able to mix and match which wavelengths you would like to combine to create the light you want. The most striking display of this is with red, green and blue LEDs which can be used to create virtually every visible color. Most recently is the introduction of tunable white light which allows the user to move along the black body curve and adjust the light to whichever white light suits the activity or mood as needed.
Light
Light comes in both visible and invisible wavelengths. The visible spectrum starts at about 380 nm and goes through about 700 nm. Outside of this range lie the invisible spectrums. Some of the more well known invisible spectrums that lie just outside on either side are ultraviolet (UV) and infrared (IR).
The chart shown to the left is the weighted response of the human eye. Your eye is far more receptive to green light than any of the other colors. Many of the other colors we see very poorly. This is where challenges begin to develop for lighting manufacturers. If the light is slightly off in one color direction and placed next to another it will be noticeable to the end user. This is even more evident with LEDs because blue LEDs are most robust when it comes to temperature, where as, red LEDs are very susceptible to temperature. This is where need for controls inside the light becomes very important.
This chart also shows were the white light lands on this scale. White light follows what is known as the black body curve. This curve is the black line that goes through the middle of the chart. We commonly refer to white light by its color temperature and it is somewhat counter intuitive for how we think of temperature. More red, or warm, white light is lower on the temperature scale. Where blue, or cool, white light is higher on the temperature scale. With temperature we use Kelvins as the unit of measure.
Tuning White Light
Tuning white light is rapidly becoming more and more important as more research is done on how humans respond to light. Now we need to be able to use that research and make products around it. Newer LED bulbs are having the ability to switch the color they produce by mixing and matching the colors. Now more controls are need to be able to handle the multiple channels that the light bulb requires.
