Abstract:
PROBLEM TO BE SOLVED: To provide an organic electroluminescent element, specifically suitable for use in a light source for a lighting system, by obtaining white light high in color temperature and color rendering properties.SOLUTION: An organic electroluminescent element includes a plurality of light emitting units, each of which includes a luminous layer comprising at least an organic compound, between an anode and a cathode. White light obtained by the emission of the light emitting units has an emission spectrum S continuous over a wavelength region of at least 380-780 nm, and has one peak wavelength pin a red wavelength region R at 600-640 nm, one peak wavelength pin a green wavelength region G at 500-540 nm, and two wavelengths p, pin a blue wavelength region B at 440-490 nm, in the emission spectrum S.
Abstract:
PROBLEM TO BE SOLVED: To provide a method for evaluating light source color angle dependency of a planar light source, capable of obtaining an evaluation result matched with human sensation.SOLUTION: The light source color angle dependency of the planar light source is evaluated by a first step which while changing an angle of a planar light source at a predetermined pitch angle, measures chromaticity and brightness of the planar light source at each angle, a second step for determining reference chromaticity, a third step for calculating a color difference between the chromaticity and the reference chromaticity at each angle, a fourth step for calculating a weighted color difference obtained by weighting the color different at each angle by the brightness, and a fifth step for outputting a sum of all weighted color differences as an evaluation value of the light source color angle dependency.