Spectral power distribution

CIE standard illuminant spectral power distribution comparisons referenced to the human visual system photopic response

In radiometry, photometry, and color science, a spectral power distribution (SPD) measurement describes the power per unit area per unit wavelength of an illumination (radiant exitance). More generally, the term spectral power distribution can refer to the concentration, as a function of wavelength, of any radiometric or photometric quantity (e.g. radiant energy, radiant flux, radiant intensity, radiance, irradiance, radiant exitance, radiosity, luminance, luminous flux, luminous intensity, illuminance, luminous emittance).[1][2][3][4]

Knowledge of the SPD is crucial for optical-sensor system applications. Optical properties such as transmittance, reflectivity, and absorbance as well as the sensor response are typically dependent on the incident wavelength.[3]

  1. ^ Mark D. Fairchild (2005). Color Appearance Models. John Wiley and Sons. ISBN 0-470-01216-1.
  2. ^ Michael R. Peres (2007). The Focal Encyclopedia of Photography. Focal Press. ISBN 978-0-240-80740-9.
  3. ^ a b William Ross McCluney (1994). Introduction to Radiometry and Photometry. Boston: Artech House. ISBN 0890066787.
  4. ^ Franc C. Grum (1979). Optical Radiation Measurements (v. 1). New York: Academic Press. ISBN 0123049016.