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Full Spectrum Lighting:
Full spectrum light is a light source with a color temperature of 5000K plus, and a Color Rendering Index (CRI - see below) of 90 plus.

Verilux states:

"Many companies have chosen to use term "full spectrum" because people instantly recognize that phrase. However, you can only achieve full spectrum in a fluorescent bulb.

Verilux coined the term natural spectrum and it is meant to describe the quality of the light without being inaccurante."

CRI - Color Rendering Index is a measure of how well colors can be perceived using light from a source, relative to light from a reference source such as daylight. By definition, an incandescent lamp has a CRI of 100. Fluorescent lamps with low CRI have phosphors that emit too little red light. Skin appears less pink, and hence "unhealthy" compared with incandescent lighting.
CRI's typically range from 62-85 for fluorescent bulbs.

See Color Rendering Index (CRI) | Topbulb and High CRI Bulbs | Topbulb
and Color Rendering Index (CRI) Explained

Color Spectra or Temperature:
Fluorescent and some LED lights come with different color temperature ratings.
In fluorescent tubes this is done by combining different phospors on the inner surface of the bulb, with LEDs it is done by locating red, green and blue LEDs adjacent to each other.
Color Name Color Temperature * Use
Soft White
or Warm
Comfort Light
2,600K -
The standard color of incandescent bulbs. †
Living rooms and bedrooms: The warm white light is an invitation to relax and enjoy life.
Warm White
3,000K -
Living areas and create a cozy lighting atmosphere.
Cool White
4,100K -
Good for kitchens and work spaces.
6,000K -
Good for reading.
the most natural and is ideally suited for lighting private working areas. Studies have shown that artificial daylight has a positive effect on wellbeing and moods and helps to promote concentration.
Plant or Aquarium
647nm to 700nm
424nm to 491nm
Plant or Aquarium
* Typical Color Temperature (in Kelvin's) or approximate Wavelength (inNanometers)
† Incandescent bulb temperatures: 2800K (60W bulb), 2870K (100W bulb), 2900K (150W bulb)

Source: Philips Lighting - Understanding the new Federal Energy Efficiency Legislation

Color temperature - Color temperature relates to the fact that when an object is heated, it will emit a color that is directly related to the temperature of that object. The higher the color temperature, the more 'blue' the light, and the lower the color temperature the more 'red' the light.
See light

Color temperature in a room or space can have a dramatic affect on the people that use that lighting to perform tasks. For example, rooms that are used for tasks such as reading can benefit by incorporating lighting on the cooler end of the scale. Many studies have been done on classroom and work settings where reading improves when done under lighting near 5500K (Day White - 5500-6000K).

See: Color temperature - Wikipedia

Color Temperature Tunable White Light LED System
Color Luminous
Flux (lm)
(nm / °C)
Cool White (CW) 45 -- 3200 K --
Warm White (WW) 20 -- 6400 K --
Red-Orange (R) 55 20 625 0.06
Amber (A) 42 14 595 0.09
Green (G) 53 35 525 0.04
Blue (B) 16 25 465 0.04

Color Temperature Light Source
1000-2000 K Candlelight
2500-3500 K Tungsten Bulb (household variety)
3000-4000 K Sunrise/Sunset (clear sky)
4000-5000 K Fluorescent Lamps
5000-5500 K Electronic Flash
5000-6500 K Daylight with Clear Sky (sun overhead)
6500-8000 K Moderately Overcast Sky
9000-10000 K Shade or Heavily Overcast Sky
See: Color Temperature Tunable White Light LED System.pdf at
Other Temperature Designations

 Color Temperature:
 WW - Warm White - 2700-3500K 
  W = White 3000-3500K
 CW - Cool White - 4000-5000K
  P =  Full Spectrum 5000-5500K (sometimes shown as 4000-4200)
  D - Daylight 6000-6500K (Note: for photography daylight is 5000-5500)
 (Note: I couldn't find what P stands for. Some links have P = Black Body or Planckian)
See Color Temperature at light in tech.

 CCT - Correlated colour temperature
 CRI - Color Rendering Index
 Lumen (lm) - Measure of light brightness
Color temperature - Wikipedia

What the Big Box Stores Won’t Tell You About LEDs - The Lightbulb Co.
Comparing SoLux and Daylight to Verilux, & Bell+Howell
Full Spectrum (FS) and Seasonal Affective Disorder
1993 American Psychological Association Convention Papers at the Institute for Research in Construction.
The Full-Spectrum Controversy
Full Spectrum Lighting at Dr. Joseph Mercola's Total Health site.

Full Spectrum Lighting -Natural Full Spectrum Lighting Comparisons, Ratings, Reviews at

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last updated 12 Nov 2013