A projection and a raised portion are formed on an upper surface of a blue-violet semiconductor laser device. A projection and a raised portion are formed on a lower surface of a red semiconductor laser device. The height of the projection is smaller than the height of the raised portion, and the height of the projection is smaller than the height of the raised portion. The blue-violet semiconductor laser device and the red semiconductor laser device are joined to each other such that the projections are opposed to each other.