The term full spectrum is most often used when referring to fluorescents that simulate natural outdoor light. By definition, virtually all fluorescent light bulbs are full spectrum in that they contain some of all colors in their spectral range. However, the term full spectrum is primarily used when referring to those lamps that fall into the white to blue/white color temperature range. Color temperature is measured by a term called kelvin. 3000 kelvin would be a warm tone color, 5000 kelvin would be a white color and 6500 kelvin would be a blue/white color.

One of the pioneers of the full spectrum fluorescent light bulb was Durotest or Durolite. For many years representatives from other manufacturers played down the full spectrum concept, perhaps due to some of the extensive theraputic claims made by Durotest. Today virtually all major manufacturers have entered the full spectrum market which is expanding every year. GE or General Electric has the Sunshine, Chroma50 and Chroma75 fluorescents. Philips has the Natural Sunshine fluorescent. Sylvania has the Design50 and Daylight fluorescent. Westinghouse has the full spectrum Realite.

To complement the full spectrum line, each major manufacturer has introduced an incandescent line of natural light. These light bulbs typically filter out or absorb the color yellow from the visible light the lamps emit. The result is that these light bulbs enhance reds and blues, making colors appear more vibrant. The most effective method in achieving this vibrancy is by using the element neodymium. Neodymium is a rare earth element that naturally absorbs the color yellow. The following is a breakdown by manufacturer:

Sylvania: Sylvania calls their line Daylight. Most of their Daylight incandescent light bulbs use a blue phosphor coating. The variety ranges from standard light bulbs to halogen called Daylight Plus. There are also Daylight appliance bulbs, indoor floods and indoor/outdoor PAR floods. The PAR floods use neodymium in the glass. Sylvania also carries a 50/150 Daylight 3way.

GE - General Electric: General Electric calls their line Reveal. Again, the incandescents use a blue phosphor coating. GE offers some decor light bulbs and globes using neodymium and a 30/100 Reveal 3way to the mix.

Philips: Philips Lighting has what is called the Natural Light. This line also uses a distinctive blue coating to produce light that is more like natural daylight. Their family includes standard, vanity globes, fan lights and a halogen line called Natural lights Plus. It appears that the halogen use neodymium.

Westinghouse: Westinghouse has the Realite. This is one of the first complete lines of the first four brands listed. Westinghouse Realite lamps produce the true, brilliant colors that natural sunlight provides. Their line includes 40, 50, 75 & 150 watt floods to fit nearly every indoor application. They also have a 50/150 watt Realite 3-way, 60-150 watt clear/frosted standard lamps and globe(G25) vanity lamps. Westinghouse also includes their full spectrum fluorescents under the Realite name. These include a 15 watt undercabinet fluorescent, an F20 24" fluorescent and an F40 4' fluorescent. The fluorescent Realite has a color rendering index (CRI) of 94 out of a possible 100. These Realite fluorescents are industry leaders in ratings and quality. The life ratings on the Realite generally exceed the other brands. In 2005 Westinghouse plans on introducing another line called Radiant. The Radiant line should be among the most extensive in the market and may eventually replace the Realite.

Verilux: Verilux makes a light box for treatment of S.A.D. or seasonal affective disorder. This box is called the Happylite Sunshine Simulator. Verilux has other product as well.

Seasonal Affective Disorder has other names such as Winter Blues, Winter Depression, Cabin Fever... This condition has often used full spectrum lighting as treatment or as a treatment supplement. Since this is considered a medical condition, all claims and treatment protocols must be filtered through the health care practitioner.