Patent ID: 8824520

Claim:
A surface emitting semiconductor laser comprising: a substrate; a first semiconductor multilayer reflector formed on the substrate, and including laminated pairs of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index; an active region formed on or above the first semiconductor multilayer reflector, and forming a resonator; a second semiconductor multilayer reflector formed on or above the active region, and including an emission surface and laminated pairs of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index; a cavity extending region formed between the first semiconductor multilayer reflector and the active region or between the second semiconductor multilayer reflector and the active region, having an optical film thickness greater than an oscillation wavelength, extending the length of the resonator of the active region, and including a conductive semiconductor material; a light confining layer formed above the substrate, and including a low refractive index region having a relatively low refractive index and a high refractive index region having a relatively high refractive index and surrounded by the low refractive index region; and an emission surface additional film formed on the emission surface of the second semiconductor multilayer reflector, and made of a material allowing the oscillation wavelength to transmit therethrough, wherein the first semiconductor multilayer reflector, the cavity extending region, the active region, and the second semiconductor multilayer reflector determine a reflection band that includes at least two resonance wavelengths, and oscillation occurs in a selected one of the resonance wavelengths, wherein the emission surface additional film includes a central portion and an outer circumferential portion having different film thicknesses to suppress possible resonance in the high refractive index region of the light confining layer and the cavity extending region, and wherein the central portion is positioned to overlap the high refractive index region of the light confining layer, and the outer circumferential portion is positioned to overlap the low refractive index region of the light confining layer.