Full-spectrum light is light that covers the electromagnetic spectrum from infrared to near-ultraviolet, or all wavelengths that are useful to plant or animal life; in particular, sunlight is considered full spectrum, even though the solar spectral distribution reaching Earth changes with time of day, latitude, and atmospheric conditions.
Products marketed as "full-spectrum" may produce light throughout the entire spectrum, but actually do not produce an even spectral distribution, and may not even differ substantially from lights not marketed as "full-spectrum".
Color temperature and Color Rendering Index (CRI) are the standards for measuring light. There is no technical definition of "full-spectrum" so it cannot be measured. To compare "full-spectrum" sources requires direct comparison of spectral distributions.
Use in art and in color matching
Full-spectrum fluorescent lamps are used in the art studio by artists who paint pictures on canvas when they paint at night or inside (ideally, during the day the art studio should have north sunlight[clarification needed], but many artists don't have access to north sunlight so they use full-spectrum lamps instead) in order to make sure that the colors they are using appear in their natural hue as they will appear when the painting is displayed in a home or in an art gallery.
Full-spectrum lamps are also used by color scientists or color matchers in paint stores to match colors at night or inside when they don't have access to north sunlight.
Use in Aquariums
Full spectrum lighting is used both for tropical and marine fish as well as many other water pets. The use of full spectrum lighting assists aquarium plants to grow and aids in the health of the fish and the tank as a whole.
Use in gardening
Use in seasonal affective disorder
In recent years, full-spectrum lighting has been used in the treatment of seasonal affective disorder (SAD) through the use of "light boxes" that mimic natural sunlight, which may not be available in some areas during the winter months. Light is an environmental stimulus for regulating circadian cycles.
Lightbox therapy, otherwise known as phototherapy, is a recognized modality for depression (such as SAD). It is also the primary treatment for circadian rhythm sleep disorders. Depending on the quality of the light, it is estimated that 10,000 lux is needed for effective treatment. Not all light boxes are the same, and some produce only blue or green light.
The non-profit Lighting Research Center, a group of utility companies, experts and government agencies, established the National Lighting Product Information Program (NLPIP) in the USA to provide objective information about the effectiveness of different lighting systems. According to the NLPIP, full-spectrum light does not provide any improved benefits over similar light systems.
The National Research Council of Canada Institute for Research in Construction, a Canadian government research and development agency, has published several scientific articles about full-spectrum lighting, collected on their web page. The authors of these papers also have concluded that full-spectrum lighting (~5000 K, CRI>90) does not confer any benefits on performance, mood, or health compared to typical cool-white fluorescent lighting.
- "Full-spectrum Light Sources". Lighting Answers 7 (5). September. Retrieved 2007-11-01.
- Galidakis, I.N. "The Double Amici Prism Hand-Held Spectroscope". Retrieved 2007-11-01.
- Full-Spectrum Light Sources - Light Research Center
- Sylvania's Statement on FS Lighting with US Gov links Sylvania PDF
- "Cornell study finds full-spectrum lighting has no effect on restaurant sales". Cornell Chronicle. 2007-09-14. Retrieved 2007-11-01.
- McColl, S.L.; Veitch, J.A. "Full-spectrum fluorescent lighting: a review of its effects on physiology and health," Psychological Medicine, 31, (6), August, pp. 949-964, 2001 (NRCC-43097)
- Veitch, J.A.; McColl, S.L. "A Critical examination of perceptual and cognitive effects attributed to full-spectrum fluorescent lighting," Ergonomics, 44, (3), February, pp. 255-279, February 01, 2001 (NRCC-42840).
- Gifford, Robert. Scientific Evidence for Claims about Full-Spectrum Lamps: Past and Future (PDF).