A three-color light source 1 is a three-color light source that combines red, green, and blue laser light so as to output light. The three-color light source 1 includes a red LD 11, a green LD 12, a blue LD 13, a first collimator lens 61, a second collimator lens 62, a third collimator lens 63, a first wavelength filter 81, a second wavelength filter 82, a carrier 30 that is equipped with the LDs 11 to 13, the collimator lenses 61 to 63, and the wavelength filters 81 and 82, and a TEC 40 that is equipped with the carrier 30. The red LD 11 is formed of a GaAs-based material, and the green LD 12 and the blue LD 13 are formed of GaN-based materials.