A vertical cavity surface emitting laser comprising: a semiconductor substrate; a lower reflecting mirror formed on a surface of the semiconductor substrate by alternately forming layers of semiconductor films having different refraction indexes on the surface of the semiconductor substrate; an active layer formed on the lower reflecting mirror from a semiconductor material; a selective oxidization layer formed on the active layer that is partially oxidized, forming a current confined structure; and an upper reflecting mirror formed on the selective oxidization layer by alternately forming semiconductor films having different refraction indexes, wherein a mesa structure is formed in at least the active layer, the selective oxidization layer, and the upper reflecting mirror, the vertical cavity surface emitting laser further comprising: a lower electrode connected to the semiconductor substrate; and an upper electrode connected to the upper reflecting mirror, the vertical cavity surface emitting laser emitting laser light perpendicularly to the plane of the semiconductor substrate when an electric current flows between the upper electrode and the lower electrode, wherein: the surface of the semiconductor substrate is inclined with respect to a particular plane, the active layer includes a quantum well layer having a compressive strain with respect to the substrate, and a spacer layer (13,15), characterized in that: the spacer layer (13,15) has a compressive strain with respect to the semiconductor substrate; or the spacer layer (13,15) comprises a polarisation control layer which has a compressive strain with respect to the semiconductor substrate. a semiconductor substrate; a lower reflecting mirror formed on a surface of the semiconductor substrate by alternately forming layers of semiconductor films having different refraction indexes on the surface of the semiconductor substrate; an active layer formed on the lower reflecting mirror from a semiconductor material; a selective oxidization layer formed on the active layer that is partially oxidized, forming a current confined structure; and an upper reflecting mirror formed on the selective oxidization layer by alternately forming semiconductor films having different refraction indexes, wherein a mesa structure is formed in at least the active layer, the selective oxidization layer, and the upper reflecting mirror, the vertical cavity surface emitting laser further comprising: a lower electrode connected to the semiconductor substrate; and an upper electrode connected to the upper reflecting mirror, the vertical cavity surface emitting laser emitting laser light perpendicularly to the plane of the semiconductor substrate when an electric current flows between the upper electrode and the lower electrode, wherein: the surface of the semiconductor substrate is inclined with respect to a particular plane, the active layer includes a quantum well layer having a compressive strain with respect to the substrate, and a spacer layer (13,15), characterized in that: the spacer layer (13,15) has a compressive strain with respect to the semiconductor substrate; or the spacer layer (13,15) comprises a polarisation control layer which has a compressive strain with respect to the semiconductor substrate. a lower electrode connected to the semiconductor substrate; and an upper electrode connected to the upper reflecting mirror, the vertical cavity surface emitting laser emitting laser light perpendicularly to the plane of the semiconductor substrate when an electric current flows between the upper electrode and the lower electrode, wherein: the surface of the semiconductor substrate is inclined with respect to a particular plane, the active layer includes a quantum well layer having a compressive strain with respect to the substrate, and a spacer layer (13,15), characterized in that: the spacer layer (13,15) has a compressive strain with respect to the semiconductor substrate; or the spacer layer (13,15) comprises a polarisation control layer which has a compressive strain with respect to the semiconductor substrate. the surface of the semiconductor substrate is inclined with respect to a particular plane, the active layer includes a quantum well layer having a compressive strain with respect to the substrate, and a spacer layer (13,15), characterized in that: the spacer layer (13,15) has a compressive strain with respect to the semiconductor substrate; or the spacer layer (13,15) comprises a polarisation control layer which has a compressive strain with respect to the semiconductor substrate. the spacer layer (13,15) has a compressive strain with respect to the semiconductor substrate; or the spacer layer (13,15) comprises a polarisation control layer which has a compressive strain with respect to the semiconductor substrate.