What is full spectrum lighting?

Full spectrum lighting is light that contains the entire visible spectrum of light, similar to natural sunlight. 

There is no singular, agreed-upon definition of what constitutes a full spectrum light bulb. Still, it is understood that a full spectrum light bulb replicates some of the essential qualities of natural light. Color rendering index (CRI) and color temperature represent two of the most essential and distinguishing values to determine how close a light source is to natural daylight.

Full spectrum lamps and light sources

1. Have a color rendering index (CRI) above 91. The color rendering index is a measure of a light source's ability to accurately reproduce the colors of various objects as compared with natural daylight. The index ranges from 0 to 100, 100 being the highest, and that of natural sunlight.

 2. Have a color temperature between 5000K and 6500K.* Represented in degrees Kelvin, natural daylight at noon is about 5600-6500K, though this number shifts according to geographic location and time of year. *Note that color temperature is not as important a factor as color rendering index when identifying full spectrum light.  

History and Research 

Scientific research in the 1960s has demonstrated the remarkable effects specific wavelengths of light have on all living things. Research has concluded that light containing the entire spectrum of wavelengths, from infrared to ultraviolet, is best for overall health and well-being. Interestingly, in the absence of natural sunlight, an artificial light source containing a fuller, more complete spectrum of visible light, particularly the blue wavelengths, would have just the same effect on plants as natural sunlight. And, just as plants need the sun and its full spectrum light to stimulate growth, so do we as humans need full spectrum light to trigger biological processes, which in turn promote focus, energy, and a better overall mood. 


Since a lack of natural sunlight decreases health and vitality, but we live much of our lives indoors, we should at least aim to get the most out of the lamps and light sources we use each day. This is why we believe all bulbs should be replaced with a full spectrum equivalent! Short of that, full spectrum light bulbs should be used when access to natural lighting is difficult.

Full spectrum lighting is also used in more therapeutic and concentrated bright light doses for the relief of symptoms due to the winter blues or seasonal affective disorder that affects some during the winter months. These light therapy boxes use either LED or fluorescent lights to deliver therapeutic doses of bright white light that our bodies perceive similarly to daylight, but are inherently different than full spectrum bulbs. Learn more about the difference between light therapy and full spectrum light bulbs. 

Which full spectrum light is right

People perceive colors differently, so the right full spectrum light bulb is a question of personal preference in addition to the intended application and use.

Apart from making for a beautiful home and improving how we see and feel at any time of the year, full spectrum light bulbs are also crucial for applications where high color rendering is essential, such as in art or photography. 

For residential applications, people may prefer a warmer light with a color temperature ranging between 3500K and 4500K as this color range is comforting and pleasing to the eye, while still delivering the useful health benefits of full spectrum lighting. 

For retail applications, people may want to choose a full spectrum lamp with more white light, with a color temperature ranging from 4000K to 5000K. In the office, aim for between 5000K and 6500K to increase alertness. 

In the end, no matter the type of full spectrum light you choose, by seeing and feeling better, you will enjoy doing what you love with increased comfort and joy under a better light. Now that's a real recipe for health and well-being!



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