Optical path changing device, the connection structure of optical path changing device, a light source device and an optical mounting device

Optical path changing element 4, the supporting substrate 5, made of optical crystals, wherein a support a thin layer 6 formed on a substrate, a first major surface 6a of the supporting substrate side, opposite to the supporting substrate second thin layer having a major surface 6b, and a ridge-type optical waveguide 8 which is defined by at least a pair of ridge grooves 7 which are formed in the thin layer 6, the light incident surface 8a and the optical waveguide 8 comprising a ridge type optical waveguide having a reflecting surface 8b which reflects light propagating through the. The light reflected by the reflecting surface is emitted from the surface through a thin layer.