Full-spectrum light

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.

"Full-spectrum" is not a technical term when applied to an electrical light bulb but rather a marketing term implying that the product emulates natural light.

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.

A cube of carbon "C" will radiate light of varying spectral power distribution (SPD) as it is heated. At 0 K, it is pure black, while at about 5,000 K to 5,500 K, it appears similar to noon daylight.

Ideally, during the day, the art studio should be lit with northern sunlight (in the northern hemisphere), because it is considered more neutral and diffused than the direct, "yellowish" quality of southern sunlight. Since many artists' studios don't have north-facing windows, full-spectrum lamps are sometimes used to approximate such light. Full-spectrum fluorescent lamps are also used by color scientists, color matchers in paint stores and quilters and others working with fabrics or yarn when working under inadequate lighting conditions to assist in achieving the correct hues as they will later appear in daylight or under gallery lighting.

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.

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