A semiconductor component for emitting light includes a main body that comprises at least one mesa body. The mesa body has an emission region for emitting the light. The emission region is assigned a first mirror portion, a second mirror portion, and an active portion arranged between the two mirror portions and serving to produce the light. The semiconductor component further includes electrical contacts for feeding electrical energy into the active portion, with at least one stress element that is attached to a surface of the main body. The stress element is configured to generate in the main body a material stress which has an effect on one or more polarization properties of the emitted light.

An optical scanning device includes: a light source; a light source driver that provides the light source with a drive current, on which a bias current that fluctuates according to temperature change is superimposed, for emitting light from the light source; and a bias current adjuster that provides the light source driver with a bias control signal for adjusting a magnitude of the bias current, wherein the bias current adjuster includes a current value adjusting member that is capable of changing the magnitude of the bias control signal according to temperature change, and wherein the bias control signal that has automatically changed according to temperature change of the current value adjusting member is provided to the light source driver, so that the light source driver makes the magnitude of the bias current to be superimposed fluctuate, based on the provided bias control signal.

A plurality of surface emitting lasers are formed on the single surface emitting laser element. The plurality of surface emitting lasers have respective emission wavelengths selected from wavelengths satisfying condition of:
0<λ.sub.1−λ.sub.s≤5.36×10.sup.−5λ.sub.c.sup.2−×5.83×10.sup.−2λ.sub.c+32.4 where a first emission wavelength is λ.sub.1 [nm], a second emission wavelength shorter than the first emission wavelength is λ.sub.s [nm], and a middle wavelength between the first emission wavelength and the second emission wavelength is λ.sub.c [nm]. At least one of the plurality of surface emitting lasers has an emission wavelength different from an emission wavelength of another surface emitting laser.

A plurality of surface emitting lasers are formed on the single surface emitting laser element. The plurality of surface emitting lasers have respective emission wavelengths selected from wavelengths satisfying condition of:
0<λ.sub.1−λ.sub.s≤5.36×10.sup.−5λ.sub.c.sup.2−×5.83×10.sup.−2λ.sub.c+32.4 where a first emission wavelength is λ.sub.1 [nm], a second emission wavelength shorter than the first emission wavelength is λ.sub.s [nm], and a middle wavelength between the first emission wavelength and the second emission wavelength is λ.sub.c [nm]. At least one of the plurality of surface emitting lasers has an emission wavelength different from an emission wavelength of another surface emitting laser.

Provided is a reservoir computing system including a reservoir having a random laser for emitting a non-linear optical signal with respect to an input signal. The reservoir computing system also includes a converter for converting the non-linear optical signal into an output signal by applying a conversion function. The conversion function is trained by using a training input signal and a target output signal.

A light source module that emits a combined laser beam, and includes: a plurality of semiconductor laser elements; and a control circuit that controls power of a laser beam emitted by each of the semiconductor laser elements. The semiconductor laser elements include: a first element group that emits a first laser beam; and a second element group that emits a second laser beam. The combined laser beam includes at least one of the first laser beam or the second laser beam. The control circuit maintains an average combined-beam wavelength that is an average wavelength of the combined laser beam constant for a change in power of the combined laser beam. When the power of the first laser beam and the power of the second laser beam are equal to each other, an average wavelength of the first laser beam is longer than an average wavelength of the second laser beam.

A light source module that emits a combined laser beam, and includes: a plurality of semiconductor laser elements; and a control circuit that controls power of a laser beam emitted by each of the semiconductor laser elements. The semiconductor laser elements include: a first element group that emits a first laser beam; and a second element group that emits a second laser beam. The combined laser beam includes at least one of the first laser beam or the second laser beam. The control circuit maintains an average combined-beam wavelength that is an average wavelength of the combined laser beam constant for a change in power of the combined laser beam. When the power of the first laser beam and the power of the second laser beam are equal to each other, an average wavelength of the first laser beam is longer than an average wavelength of the second laser beam.

A tunable laser includes a reflective semiconductor optical amplifier (SOA), a grating codirectional coupler, and a reflective microring resonator. The grating codirectional coupler and the reflective microring resonator are both formed on a silicon base. An anti-reflection film is disposed on a first end surface of the reflective SOA, and the first end surface is an end surface, coupled to a first waveguide of the grating codirectional coupler, of the reflective SOA. A second waveguide of the grating codirectional coupler is coupled to the first waveguide, a first grating is disposed on the first waveguide, a second grating disposed opposite to the first grating is disposed on the second waveguide, and the first grating and the second grating constitute a narrow-band pass filter. The second waveguide is connected to the reflective microring resonator.

A method or apparatus for narrowing the linewidth of a single mode laser is provided. The linewidth of a single mode laser is narrowed by injecting an optical feedback simultaneously into the first laser cavity mirror and the second laser cavity mirror of the single mode laser.

A method or apparatus for narrowing the linewidth of a single mode laser is provided. The linewidth of a single mode laser is narrowed by injecting an optical feedback simultaneously into the first laser cavity mirror and the second laser cavity mirror of the single mode laser.