A broad-spectrum laser for use in a MEMS laser scanning display device is provided. In one example, the broad-spectrum laser includes a laser diode emitter with plural quantum wells each having a different spectral peak. In another example, the broad-spectrum laser includes a laser diode emitter with a tunable absorber to achieve a broadened emissions spectrum. In another example, the broad-spectrum laser includes a laser diode emitter array having plural individual emitters with different spectral peaks.

An optical semiconductor device includes a semiconductor multilayer structure, an active region interposed between a first facet on a light emitting side and a second facet opposing to the first facet, and a first electrode layer provided on a top of the semiconductor multilayer structure and a second electrode layer provided on a bottom of the semiconductor multilayer structure; and an electrical connection region connected to at least one of the first electrode layer and the second electrode layer of the optical semiconductor device and used for injecting a current to the active region, and α>β and β>0 are satisfied where α is the contact area included in a half region on the first facet side in a top area of the optical semiconductor device and β is the contact area included in a half region on the second facet side.

A light emitting apparatus includes a laminated structure provided at a substrate and including a plurality of columnar sections. The plurality of columnar sections each includes a light emitting layer including a plurality of first well layers, a first semiconductor layer provided between the substrate and the light emitting layer and containing Ga and N, an optical confining layer provided between the first semiconductor layer and the light emitting layer and confining light in the light emitting layer, and a second well layer provided between the first semiconductor layer and the optical confining layer. The first well layers and the second well layer are made of InGaN. The optical confining layer includes an InGaN layer. The composition formula of the first well layers is In.sub.xGa.sub.1-xN. The composition formula of the InGaN layer of the optical confining layer is In.sub.yGa.sub.1-yN. The composition formula of the second well layer is In.sub.zGa.sub.1-zN. The parameters x, y, and z satisfy 0<y<z<x<1.

A semiconductor laser is provided with: an active layer that excites a transverse electric (TE) mode and a transverse magnetic (TM) mode of light and constitutes at least a part of a resonator guiding the TE mode and the TM mode of light; and a diffraction grating as a frequency difference setting structure that sets the difference in oscillation frequency between the TE mode and the TM mode of light higher than a relaxation-oscillation frequency

A broad-spectrum laser for use in a MEMS laser scanning display device is provided. In one example, the broad-spectrum laser includes a laser diode emitter with plural quantum wells each having a different spectral peak. In another example, the broad-spectrum laser includes a laser diode emitter with a tunable absorber to achieve a broadened emissions spectrum. In another example, the broad-spectrum laser includes a laser diode emitter array having plural individual emitters with different spectral peaks.

A broad-spectrum laser for use in a MEMS laser scanning display device is provided. In one example, the broad-spectrum laser includes a laser diode emitter with plural quantum wells each having a different spectral peak. In another example, the broad-spectrum laser includes a laser diode emitter with a tunable absorber to achieve a broadened emissions spectrum. In another example, the broad-spectrum laser includes a laser diode emitter array having plural individual emitters with different spectral peaks.

A semiconductor light emitting device includes a substrate, and an array including three or more light emitting elements which are aligned above and along a main surface of a substrate and each emit light. The light emitting elements each include a clad layer of a first conductivity type, an active layer containing In, and a clad layer of a second conductivity type disposed above the substrate sequentially from the substrate. Among the light emitting elements, the compositional ratio of In in the active layer is smaller in the light emitting element located in a central area in an alignment direction than that in the light emitting elements located in both end areas in the alignment direction.

A semiconductor device includes a substrate, a semiconductor laser part formed on the substrate and having an active layer with an uniform composition and a first ridge structure, and an adjacent part formed on the substrate, having a core layer with an uniform composition and a second ridge structure, and being an optical modulator or an optical waveguide which is in contact with the semiconductor laser part, wherein the first ridge structure is largest in width at a first contact part which is in contact with the second ridge structure, and the second ridge structure is largest in width at a second contact part which is in contact with the first ridge structure.

An optical semiconductor device includes a semiconductor multilayer structure, an active region interposed between a first facet on a light emitting side and a second facet opposing to the first facet, and a first electrode layer provided on a top of the semiconductor multilayer structure and a second electrode layer provided on a bottom of the semiconductor multilayer structure; and an electrical connection region connected to at least one of the first electrode layer and the second electrode layer of the optical semiconductor device and used for injecting a current to the active region, and > and >0 are satisfied where is the contact area included in a half region on the first facet side in a top area of the optical semiconductor device and is the contact area included in a half region on the second facet side.

An etched planarized VCSEL includes: an active region; a blocking region over the active region, and defining apertures therein; and conductive channel cores in the apertures, wherein the conductive channel cores and blocking region form an isolation region. A method of making the VCSEL includes: forming the active region; forming the blocking region over the active region; etching the apertures in the blocking region; and forming the conductive channel cores in the apertures of the blocking region. Another etched planarized VCSEL includes: an active region; a conductive region over the active region, and defining apertures therein; and blocking cores in the apertures, wherein the blocking cores and conductive region form an isolation region. A method of making the VCSEL includes: forming the active region; forming the conductive region over the active region; etching the apertures in the conductive region; and forming the blocking cores in the apertures of the conductive region.