An electroluminescent device includes, for example, first to third optical output parts respectively corresponding to red, green, and blue colors and each having a light-emitting layer. A visibility spectrum curve has an inclination value corresponding to the first optical output part, an inclination value corresponding to the second optical output part, and an inclination value corresponding to the third optical output part. Each inclination value corresponds to an emission peak wavelength at which an emission spectrum of a light ray emitted from the light-emitting layer of the corresponding optical output part reaches a maximum intensity value. The inclination values have the following relationship: first optical output part>second optical output part>third optical output part. The emission spectra of the optical output parts have widths in the following relationship: first optical output part>second optical output part>third optical output part.