A light source device and a lighting device

The invention relates to a light source device and a lighting device. The light source device can obtain a brightness much higher than the brightness obtained via the conventional mode, and comprises a fixed light source capable of emitting the light of a predetermined wavelength which is in wavelength regions of an ultraviolet light wavelength and a visible light wavelength; and a wavelength conversion layer comprising at least one type of phosphor material which come from the light excitation of the fixed light source, and emits the fluorescence of which the wavelength is longer than that of the light emitted from the fixed light source. The fixed light source and the wavelength conversion layer can be separated with each other in space, and the light source device can employ the mode of extracting at least part of fluorescence from the incidence plane of the wavelength conversion layer, wherein the excitation light comes from the fixed light source penetrates the incidence plane of the wavelength conversion layer to enter in the wavelength conversion layer. The wavelength conversion layer comprises a surface structure possessing depression or protrusion.