A semiconductor light emitting element is equipped with a layered structure including an active layer, and electrode layers at the upper and lower surfaces thereof. At least one of the upper and lower electrode layers is divided into at least two electrodes, which are separated in the wave guiding direction of light. The active layer is structured to have different gain wavelengths along the wave guiding direction, to emit light having different spectra from each region corresponding to each of the at least two electrodes. The spectral distribution of output light is enabled to be varied by individually varying the current injected by each of the at least two divided electrodes.