Display Engineering Units and Conversions

The conversion of radiated power (F in watts) to luminous flux (F in lumens) is achieved by considering the variation with wavelength of the human eye s photopic response. Then the spectral power from the source (P in, for example, W/nm) is convoluted with the relative spectral response of the eye (V tabulated by the CIE) according to  

The CIE color coordinates are obtained by a similar procedure, repeating the convolution for each of the tabulated color matching functions that describe the response of the ideal observer s blue, green, and red cones (b, g, O). 

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