A quantum cascade laser device includes a QCL element; a lens; and a lens holder having a small-diameter hole, a large-diameter hole, and a counterbore surface. At least a part of a side surface of the lens is fixed to an inner surface of the large-diameter hole in a state where an edge portion of an incident surface of the lens is in contact with the counterbore surface. A central axis of the small-diameter hole is eccentric from that of the large-diameter hole. The side surface of the lens is positioned with respect to the inner surface of the large-diameter hole along a direction from the central axis of the large-diameter hole toward the central axis of the small-diameter hole. A central axis of the lens is disposed at a position closer to the central axis of the small-diameter hole than to the central axis of the large-diameter hole.

A thermoelectric device and method of use thereof are provided for cooling and powering a laser device. The thermoelectric device comprises a first side, a second side, and a plurality of thermoelectric elements disposed therebetween. The thermoelectric device engages a photodiode array of the laser device, such that when heat is generated by the photodiode array, the thermoelectric device passively cools the photodiode array by receiving the heat and converts the heat generated to electricity to power the laser device.

An optical module includes a light-forming unit to form light. The light-forming unit includes a base member having an electronic temperature control module, a base plate, a plurality of submounts, and a microelectromechanical system (MEMS) base. The light-forming unit also includes a plurality of laser diodes arranged on the submounts, a filter arranged on the base plate and located to receive the light emitted from the plurality of laser diodes and multiplex the emitted light, a MEMS arranged on the MEMS base and located to receive the light multiplexed by the filter. The MEMS includes a scanning mirror to scan the light multiplexed by the filter, and the electronic temperature control module regulates a temperature range of the MEMS. The light-forming unit also includes a protective member surrounding and sealing the light-forming unit, which includes a base body and a lid welded to the base body.

An optical transmission module includes a metal base including a signal terminal which extends along a first direction, a dielectric block including a dielectric substance, the dielectric block having a semiconductor plane, an optical plane, and a thermal plane, the semiconductor plane and the optical plane being parallel to the first direction, the thermal plane crossing the first direction, and the semiconductor plane being provided between the optical plane and the thermal plane in the first direction, an optical semiconductor element mounted on the semiconductor plane, the optical semiconductor element being electrically connected with the signal terminal, a temperature regulating element provided between the dielectric block and the metal base in the first direction, the temperature regulating element being contacted with the thermal plane, and a lens mounted on the optical plane.

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 optical semiconductor device is applied to a ridge-stripe type laser.

A method (900) includes a gain current (I.sub.GAIN) to an anode of a gain-section diode (D.sub.0) disposed on a shared substrate of a tunable laser (310), delivering a modulation signal to an anode of an Electro-absorption section diode (D.sub.2) disposed on the shared substrate of the tunable laser, and receiving a burst mode signal (330) indicative of a burst-on state or a burst-off state. When the burst mode signal is indicative of the burst-off state, the method includes sinking a sink current (I.sub.SINK) away from the gain current at the anode of the gain-section diode. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method includes ceasing the sinking of the sink current away from the gain current and delivering an overshoot current (I.sub.OVER) to the anode of the gain-section diode.

The present invention relates to an assembly of a temperature regulating device for a semiconductor laser.

The essence of the present invention is that a flat thermally conductive surface of said device is used as a thermally conductive base surface, the assembly further contains two fixing plates which are rigidly fastened to said thermally conductive base surface and adjoin the opposite lateral sides of a lower thermally insulated surface of a thermoelectric element, said surface being in contact with the thermally conductive base surface to prevent the longitudinal and transverse displacements of the thermoelectric element along the thermally conductive base surface, and a thermally conductive plate is rigidly fastened to the thermally conductive base surface and is thermally insulated therefrom.

A laser source assembly is based upon an optical reference substrate that is utilized as a common optical reference plane upon which both a fiber array and a laser diode array are disposed and positioned to provide alignment between the components. Passive optical components used to provide alignment between the laser diode array and the fiber array are also located on the optical reference substrate. A top surface of the reference substrate is patterned to include alignment fiducials and bond locations for the fiber array receiving block, laser diode array submount and passive optical components. The receiving block is configured to present the optical fibers at a height that facilitates alignment with the output beams from the laser diodes positioned on the silicon submount.

A beam combining device and method for a Bragg grating external-cavity laser module has a plurality of side by side light-emitting modules that use a Bragg grating to perform wavelength locking. Output light of the modules is incident to a beam combining element after passing through a focusing optical element for beam combining, and light subjected to beam combining is reflected partially and transmitted partially under the effect of a light splitting element. A part is incident into a dispersion element at a diffraction angle of the element. Parallel light is formed under the effect of a conversion optical element. Spots of the light beams of corresponding wavelengths of the light-emitting modules are formed on an image acquisition mechanism. Whether the wavelengths of the corresponding light-emitting modules are locked is determined by whether there is a deviation between preset spots and spots formed by the module on the acquisition mechanism.

A laser module includes a gain chip, temperature sensors, a case, and a thermoelectric cooler (TEC). The gain chip emits a laser beam. One of the temperature sensors measures a first temperature of the gain chip and is encompassed by the gain chip. The other temperature sensor is adhered to the case and measures a second temperature. The TEC tunes the laser beam emitted by the gain chip to a desired wavelength by varying the first temperature of the gain chip through a set of third temperatures for various values of the second temperature. The set of third temperatures is selected from various values of the first temperature such that the laser beam emitted at the set of third temperatures is mode-hop free.