A semiconductor laser includes an active layer which emits laser light and cladding layers being formed so as to sandwich the active layer. The active layer includes a quantum dot layer including a plurality of quantum dots, which respectively confine movements of carriers in the three-dimensional directions. The laser radar device includes a light projection part which projects laser light and a light receiving part which receives reflected light of the laser light. The light projection part includes the semiconductor laser and a scanner which reflects the laser light, emitted from the semiconductor laser, to form a scanning laser light.

Provided is a semiconductor light source element or an optical device including a semiconductor optical waveguide of a high-mesa semi-insulated embedded structure having a window structure made of the same material as an overclad layer at a light emission end, and a method for manufacturing thereof, in which an active layer at a portion of the window structure is removed, and then the same layer as the overclad layer is formed.

In a laser system according to an aspect of the present disclosure, the following components are disposed: a first container that accommodates a first heater and a first crystal holder holding a first nonlinear crystal and includes a first light incident window via which laser light is incident and a first light exit window via which the laser light exits; a second container that accommodates a second heater and a second crystal holder holding a second nonlinear crystal and includes a second light incident window via which the laser light is incident and a second light exit window via which the laser light exits; and a stage that holds the first and second containers. A controller controls the stage to move the first nonlinear crystal away from the optical path of the laser light and inserts the second nonlinear crystal into the optical path of the laser light.

A laser chip including a plurality of stripes is disclosed, where a laser stripe can be grown with an initial optical gain profile, and its optical gain profile can be shifted by using an intermixing process. In this manner, multiple laser stripes can be formed on the same laser chip from the same epitaxial wafer, where at least one laser stripe can have an optical gain profile shifted relative to another laser stripe. For example, each laser stripe can have a shifted optical gain profile relative to its neighboring laser stripe, thereby each laser stripe can emit light with a different range of wavelengths. The laser chip can emit light across a wide range of wavelengths. Examples of the disclosure further includes different regions of a given laser stripe having different intermixing amounts.

A laser chip including a plurality of stripes is disclosed, where a laser stripe can be grown with an initial optical gain profile, and its optical gain profile can be shifted by using an intermixing process. In this manner, multiple laser stripes can be formed on the same laser chip from the same epitaxial wafer, where at least one laser stripe can have an optical gain profile shifted relative to another laser stripe. For example, each laser stripe can have a shifted optical gain profile relative to its neighboring laser stripe, thereby each laser stripe can emit light with a different range of wavelengths. The laser chip can emit light across a wide range of wavelengths. Examples of the disclosure further includes different regions of a given laser stripe having different intermixing amounts.

Provided is a semiconductor chip that can reduce the man-hours for mounting on an optical module, a subcarrier, or the like, and reducing the dedicated area of the subcarrier or the like. The semiconductor chip includes a waveguide that is terminated inside at an output end portion from which light is emitted, without contacting an emission end face, and a window region made of a bulk semiconductor and disposed between the waveguide and the emission end face, wherein the semiconductor chip is provided with an open groove formed in the output end portion so that the emission end face is a side wall formed by etching.

A semiconductor laser includes an active layer which emits laser light and cladding layers being formed so as to sandwich the active layer. The active layer includes a quantum dot layer including a plurality of quantum dots, which respectively confine movements of carriers in the three-dimensional directions. The laser radar device includes a light projection part which projects laser light and a light receiving part which receives reflected light of the laser light. The light projection part includes the semiconductor laser and a scanner which reflects the laser light, emitted from the semiconductor laser, to form a scanning laser light.

A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

A laser chip including a plurality of stripes is disclosed, where a laser stripe can be grown with an initial optical gain profile, and its optical gain profile can be shifted by using an intermixing process. In this manner, multiple laser stripes can be formed on the same laser chip from the same epitaxial wafer, where at least one laser stripe can have an optical gain profile shifted relative to another laser stripe. For example, each laser stripe can have a shifted optical gain profile relative to its neighboring laser stripe, thereby each laser stripe can emit light with a different range of wavelengths. The laser chip can emit light across a wide range of wavelengths. Examples of the disclosure further includes different regions of a given laser stripe having different intermixing amounts.

In a laser system according to an aspect of the present disclosure, the following components are disposed: a first container that accommodates a first heater and a first crystal holder holding a first nonlinear crystal and includes a first light incident window via which laser light is incident and a first light exit window via which the laser light exits; a second container that accommodates a second heater and a second crystal holder holding a second nonlinear crystal and includes a second light incident window via which the laser light is incident and a second light exit window via which the laser light exits; and a stage that holds the first and second containers. A controller controls the stage to move the first nonlinear crystal away from the optical path of the laser light and inserts the second nonlinear crystal into the optical path of the laser light.