Abstract: A vertical cavity surface emitting laser (VCSEL) includes a semiconductor substrate, a lower reflecting mirror formed on the semiconductor substrate, and a mesa structure. The mesa structure includes an active layer, a selective oxidization layer that includes a current confined structure, and an upper reflecting mirror. A lower electrode is connected to the semiconductor substrate, and an upper electrode is connected to the upper reflecting mirror. The VCSEL emits laser light perpendicularly to the plane of the semiconductor substrate when an electric current flows between the upper electrode and the lower electrode. The semiconductor substrate is inclined with respect to (100) plane. The active layer includes a quantum well layer having a compressive strain with respect to the substrate, and a spacer layer. The spacer layer has either a compressive strain or a tensile strain with respect to the semiconductor substrate.