A print head includes a platform with a face whose portion covered with a heat conductor includes a heat release section, which is deformed relative to a substantially flat portion of the face of the platform to be located at a smaller distance from the surface of the chip in a direction normal to the face at a side near to the light emission area in the longitudinal direction of the light source panel than at another side far from the light emission area. Alternatively, the heat conductor, when disconnected from the face of the platform, is thicker at a side near to the light emission area in the longitudinal direction of the light source panel than at another side far from the light emission area.