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Photometry (Chapter of Handbook of Visual Optics)



Yoshihiro Ohno


The fundamental concept of photometry, the definition of the photometric base unit candela, and the spectral luminous efficiency function V(lambda) are first introduced. Then definitions of important photometric quantities and units, such as luminous flux (lumen), luminous intensity (candela), and other units are presented and explained. Also, the fundamentals of colorimetry including color matching functions, chromaticity diagrams, correlated color temperature are presented. Important principles in photometry, including Inverse square law, Lambert's cosine law and Planck's law are introduced. The chapter concludes with future prospect for photometry.
Handbook of Visual Optics
Publisher Info
Taylor & Francis, Abingdon, -1


photometry, candela, lumen, troland, luminous flux, luminous intensity, spectral luminous efficiency function, color matching functions, chromaticity, correlated color temperature


Ohno, Y. (2017), Photometry (Chapter of Handbook of Visual Optics), Taylor & Francis, Abingdon, -1 (Accessed July 22, 2024)


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Created April 25, 2017, Updated January 8, 2018