Changes in Chromaticity Coordinates of Laser and LED Light Sources Due to Nonlinearity of Array Spectroradiometers

Consideration of nonlinearity properties of array-spectroradiometers is important in the fields of photometry, radiometry, and colorimetry. The nonlinearity properties of two commercial array-spectroradiometers were investigated, and the maximum nonlinear behavior of 24 % was observed. The errors in the measurement of chromaticity coordinates (x, y) by these array-spectroradiometers due to the nonlinearity were investigated using three white light sources based on light emitting diodes and laser diodes. It was found that 24 % nonlinearity caused the change of chromaticity coordinates up to 0.018. Correction of a spectroradiometer with respect to the nonlinearity would enable us to obtain accurate colorimetric data for light sources.