An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The quantum well active layer is doped with 0.3 to 1×10.sup.18/cm.sup.3 of n-type impurity.

A method of determining initial parameters and target values for tuning an emission wavelength of a wavelength tunable laser capable of emitting laser light in a substantial wavelength range is disclosed. The method iterates an evaluation of initial parameters and target values at target wavelengths in a preset order. The evaluation includes steps of supplying empirically obtained parameters to the t-LD, confirming whether the t-LD generates an optical beams, determining the initial parameters and the target values by carrying out feedback loops of the AFC and the APC when the t-LD generates the optical beam, or shifting the wavelength range so as to exclude the current target wavelength when the t-LD generates no optical beam.

A thermoelectric module includes a substrate; a thermoelectric element; a bonding portion including an electrode that bonds the substrate and the thermoelectric element; an organic material film that covers a front surface of the bonding portion; and an inorganic material film that covers the organic material film.

An apparatus for cooling electronic circuitry components and photonic components. In examples of the disclosure at least one photonic component is positioned overlaying at least one electronic circuitry component. In examples of the disclosure there is also provided a spacer for spacing the at least one electronic circuitry component and the at least one photonic component, wherein the spacer for spacing are thermally insulating. In examples of the disclosure there is also provided a first heat transfer configured to remove heat from the at least one electronic circuitry component, and a second heat transfer configured to remove heat from the at least one photonic component.

A laser comprising a laser cavity formed by a first optical reflector, a gain region, a second optical reflector having a plurality of reflection peaks, and at least one optically active region. The first mirror may be a DBR or comb mirror and the second mirror may be a comb mirror. The spectral reflectance of the second optical reflector is adjusted at least partially based on an electric signal received form the optically active region such that only one reflection peak is aligned with a cavity mode formed by the first and second reflector.

A transmitting unit of a LIDAR device includes at least two radiation sources for generating and emitting punctiform or linear electromagnetic beams into a scanning range, at least one of the radiation sources including an operating temperature settable as a function of an emission angle of the electromagnetic beams generated by the at least one radiation source. The different operating temperatures can generate beams having angle-dependent emission wavelengths, which can result in an improvement of the signal-to-noise ratio of a LIDAR device.

An excess heat-generating element is coupled to a heat sink through a heat conduction path. A thermal switch is mounted in the heat conduction path. A temperature-sensitive element is coupled to the heat conduction path on a same side of the thermal switch as the excess heat-generating element. A temperature monitor is mounted adjacent the temperature-sensitive element. A temperature controller has an input coupled to the temperature output of the temperature monitor and an output control line coupled to an input of the thermal switch. The temperature controller switches off the thermal switch, in response to detecting a temperature below a temperature threshold from the temperature output. When the thermal switch it off, it impedes heat flow from the excess heat-generating element to the heat sink, and the heat flow is redirected to increase heat flow from the excess heat-generating element to the heat-sensitive element.

A disclosed semiconductor laser module includes a semiconductor laser device; a semiconductor optical amplifier configured to receive laser light emitted from the semiconductor laser device and amplify the laser light that has been received; and a first light receiving device that measures an intensity of a part of the laser light emitted from the semiconductor laser device, for monitoring a wavelength of the laser light, wherein the semiconductor optical amplifier is located rearward in relation to a light receiving surface of the first light receiving device along a propagation direction of the laser light emitted from the semiconductor device.

A disclosed semiconductor laser module includes a semiconductor laser device; a waveguide optical function device that has an incidence end on which laser light emitted from the semiconductor laser device is incident and that guides the incident light; and a protrusion that is provided on an extension line of a light path of the laser light emitted from the semiconductor laser device, the extension line extending beyond the incidence end.

A device, and method of operating the device, are disclosed. The device includes: a heat spreader having a first side and a second side opposite the first side, the heat spreader including at least one oscillating heat pipe arranged between the first side and the second side, at least one of the at least one oscillating heat pipe including a plurality of interconnected channels including a working fluid; at least one optoelectronic component coupled to the first side of the heat spreader; and at least one thermoelectric cooler, wherein a cold side of the at least one thermoelectric cooler is coupled to the second side of the heat spreader. The heat spreader may include one or more heat exchange features.