Lighting Answers

Lighting Answers:Manufacturers of full-spectrum light sources have claimed a variety of benefits for their products, including better visibility, improved color rendering, better health, and greater productivity. Light sources promoted as full-spectrum can cost over ten times as much as nearly identical products that do not bear the full-spectrum claim. This report addresses questions about full-spectrum light sources: What are full-spectrum light sources? How valid are the claimed benefits? Are these products worth the extra cost? This report also proposes a convenient definition for full-spectrum light sources that can be used to quantify the extent to which a given light source deviates from a full-spectrum light source. This revision presents an improved calculation method for this new full-spectrum metric.