Editing Spectroradiometer (section)

==Spectral power distribution==
{{main|spectral power distribution}}

The spectral power distribution (SPD) of a source describes how much flux reaches the sensor over a particular wavelength and area. This effectively expresses the per-wavelength contribution to the radiometric quantity being measured. The SPD of a source is commonly shown as an SPD curve. SPD curves provide a visual representation of the color characteristics of a light source, showing the radiant flux emitted by the source at various wavelengths across the visible spectrum<ref>GE Lighting. "Learn About Light: Spectral Power Distribution Curves: GE Commercial Lighting Products." Learn About Light: Spectral Power Distribution Curves: GE Commercial Lighting Products. N.p., n.d. Web. 10 Dec. 2013. <{{cite web |url=http://www.gelighting.com/na/business_lighting/spectral_power_distribution_curves/ |title=Learn About Light: Spectral Power Distribution Curves: GE Commercial Lighting Products |access-date=2013-12-11 |url-status=dead |archive-url=https://web.archive.org/web/20131214001859/http://www.gelighting.com/na/business_lighting/spectral_power_distribution_curves/ |archive-date=2013-12-14 }}></ref> It is also a metric by which we can evaluate a light source's ability to render colors, that is, whether a certain color stimulus can be properly rendered under a given [[illuminant]].
 
[[Image:Spectral Power Distributions.png|center|frame|Characteristic spectral power distributions (SPDs) for an [[Incandescent light bulb|incandescent lamp]] (left) and a [[fluorescent lamp]] (right). The horizontal axes are in [[nanometer]]s and the vertical axes show relative intensity in arbitrary units.]]