An optoelectronic device that radiates mixed light including a first semiconductor light source which radiates light in a first wavelength range at a first intensity, a second semiconductor light source which radiates light in a second wavelength range at a second intensity, a third semiconductor light source which radiates light in a third wavelength range at a third intensity, a resistance element having a temperature-dependent electrical resistance, and a semiconductor light source control element that controls the intensity of the third semiconductor light source.