A light emitting device includes a base, a lid portion, a plurality of semiconductor laser elements, and a collimate lens. The lid portion is fixed to the base to define a hermetically sealed space by the lid portion and the base. The semiconductor laser elements are provided in the hermetically sealed space. The collimate lens has a non-lens portion fixed to the lid portion, and a plurality of lens portions connected and aligned along one direction and surrounded by the non-lens portion when viewed from a light extracting surface side of the collimate lens.

A light source device includes: a substrate having a support face; a plurality of light emitting elements disposed on the support face, the plurality of light emitting elements including a first light emitting element and a second light emitting element, each of which is a vertical-cavity surface-emitting laser element; and a planar lightwave circuit having a light incident face that faces the support face and including a plurality of optical waveguides configured to guide light that has exited from the respective plurality of light emitting elements and entered the light incident face. The planar lightwave circuit is directly or indirectly supported by the plurality of light emitting elements. The substrate includes a first wiring layer electrically connected to the first light emitting element and the second light emitting element.

To provide a semiconductor optical device with device resistance reduced for optical communication. The semiconductor optical device includes an active layer (306) for emitting light through recombination of an electron and a hole; a diffraction grating (309) having a pitch defined in accordance with an output wavelength of the light emitted; a first semiconductor layer (311) including at least Al, made of In and group-V compound, and formed on the diffraction grating; and a second semiconductor layer (307) including Mg, made of In and group-V compound, and formed on the first semiconductor layer (311).

A light emitting device includes a base, a lid portion, a plurality of semiconductor laser elements, and a collimate lens. The lid portion is fixed to the base to define a hermetically sealed space by the lid portion and the base. The semiconductor laser elements are provided in the hermetically sealed space. The collimate lens has a non-lens portion fixed to the lid portion, and a plurality of lens portions connected and aligned along one direction and surrounded by the non-lens portion when viewed from a light extracting surface side of the collimate lens.

An optical apparatus includes a light emitting device and a substrate. The light emitting device includes a base including a main body portion containing a ceramic material and wire portions exposed from the main body portion on the lower surface of the base, a lid portion fixed to the base so that a hermetically sealed space is defined by the lid portion and the base, a first semiconductor laser element emitting blue light and provided in the hermetically sealed space, a second semiconductor laser element emitting red light and provided in the hermetically sealed space, a third semiconductor laser element emitting green light and provided in the hermetically sealed space, and a collimate lens arranged on paths of the blue light, the red light and the green light. The substrate includes first metallic films electrically connected with the base of the light emitting device via the wire portions.

External cavity diode laser (ECDL) devices and methods for producing the same are described that allows ECDLs to be readily produced and configured to operate at a desired range of wavelengths, while allowing tunability of the output wavelength. One ECDL includes a laser gain chip including a gain medium, a first reflective surface at a first end of the gain medium, and a second surface at a second end of the gain medium opposite to the first reflective surface. The second surface has a facet that forms an angle approximately equal to Brewster's angle for light having a first wavelength. The ECDL further includes a diffraction grating positioned to receive light that passes through the second surface, to operate as a mirror in the external cavity diode laser, and to allow a portion of the light to be directed outside of the external cavity diode laser as output light.

An optical apparatus includes a light emitting device and a substrate. The light emitting device includes a base including a main body portion containing a ceramic material and wire portions exposed from the main body portion on the lower surface of the base, a lid portion fixed to the base so that a hermetically sealed space is defined by the lid portion and the base, a first semiconductor laser element emitting blue light and provided in the hermetically sealed space, a second semiconductor laser element emitting red light and provided in the hermetically sealed space, a third semiconductor laser element emitting green light and provided in the hermetically sealed space, and a collimate lens arranged on paths of the blue light, the red light and the green light. The substrate includes first metallic films electrically connected with the base of the light emitting device via the wire portions.

A light emitting device includes a base defining a recess, a lid portion, first and second semiconductor laser elements, and a collimate lens. The lid portion covers the recess so that a hermetically sealed space is defined by the lid portion and the base, the lid portion having a bottom surface fixed to the base and a top surface opposite to the bottom surface. The first and second semiconductor laser elements are provided in the hermetically sealed space. The first and second semiconductor laser elements respectively irradiate first and second lights having first and second peak wavelengths in a visible range. The collimate lens is fixed on the top surface of the lid portion with an adhesive. The collimate lens has a plurality of lens portions including a first lens portion through which the first light passes, and a second lens portion through which the second light passes.

Provided is a semiconductor laser element including: a substrate; and a laser array section located above the substrate and having a plurality of light emitting parts which are arranged next to each other and which emit laser beams, wherein when the wavelengths of the laser beams respectively emitted from the plurality of light emitting parts are plotted in correspondence with the positions of the plurality of light emitting parts, among a plurality of points respectively corresponding to the wavelengths plotted, the point with an extreme value is not located at a position corresponding to the center of the laser array section and is located at a position corresponding to a place separated from the center of the laser array section.

External cavity diode laser (ECDL) devices and methods for producing the same are described that allows ECDLs to be readily produced and configured to operate at a desired range of wavelengths, while allowing tunability of the output wavelength. One ECDL includes a laser gain chip including a gain medium, a first reflective surface at a first end of the gain medium, and a second surface at a second end of the gain medium opposite to the first reflective surface. The second surface has a facet that forms an angle approximately equal to Brewster's angle for light having a first wavelength. The ECDL further includes a diffraction grating positioned to receive light that passes through the second surface, to operate as a mirror in the external cavity diode laser, and to allow a portion of the light to be directed outside of the external cavity diode laser as output light.