What are they?
Full spectrum lamps are designed to emulate the full electromagnetic spectrum of light, which would most commonly be recognized as midday sunlight in terms of its appearance to the human eye. These lamps come in a variety of wattages, voltages, sizes, finishes, and base types.
How do they work?
The function of full spectrum lighting depends on the type of lamp being used to create it. There is no technical definition for full-spectrum lighting, so it is difficult to measure what defines it specifically. Full spectrum lighting generally falls within two larger lighting types: Incandescent and fluorescent.
Full spectrum incandescent lamps generally use a neodymium glass enclosure in order to filter out some of the more dominant “warm” colors that make regular incandescent light look yellow when compared to sunlight. These lamps appear lavender or purple when turned off.
Full spectrum fluorescent lighting uses a mix of phosphors in order to reach wider ranges of the Kelvin color temperature scale. They appear much “whiter” and closer to daylight than typical fluorescent lamps. The lamps look white when unlit, similar to typical fluorescent lamps. They are also generally designed to represent colors more accurately and usually have a moderate to high Color Rendering Index (CRI).
Practically, full spectrum lighting is not generally expected to provide the range in spectrum and Kelvin temperature that sunlight does, but it is designed to emulate that quality or hue of visible light.
Where are they used?
Full spectrum lighting is used in a number of different applications. Generally, it is used whenever a faithful rendering of sunlight is of primary importance. As a non-defineable term, it is also sometimes applied to other lamps which serve more specific purposes, such as plant grow lamps, aquarium lamps, and color-matching lamps.