| 摘要 |
PROBLEM TO BE SOLVED: To quantitatively measure the hue of an output light flux to maintain a target hue through feedback control.SOLUTION: A light emitting element includes emission wavelengths belonging to a plurality of types of different wavelength bands, and includes band light characteristic acquisition means for acquiring a light-emission intensity indication value correlated to the intensity of light for each of the wavelength bands and acquiring a wavelength deviation indication value correlated to deviation from a reference wavelength. An integrated control circuit creates a hue indication value correlated to the color of light and performs feedback control of a driving circuit to reduce difference between the hue indication value and a target value. The integrated control circuit, in terms of the creation of the hue indication value, holds local band color function information comprising a function value in the reference wavelength and information on change in function values of color-matching functions when a wavelength is changed from the reference wavelength for each of the color-matching functions necessary for the calculation of chromaticity, and calculates the hue indication value according to the amount of correlation with chromaticity coordinates. |
