A light source device that supplies a constant current to a diode load that includes a plurality of light-emitting elements connected in series. The light source device includes a power supply circuit connected to the diode load and a peak current limiting circuit connected in series to the diode load. The peak current limiting circuit includes a current detector that is connected in series to the diode load and a current-regulating circuit that controls a current to the diode load by a detection voltage of the current detector. Further, the current detector has a series circuit including a resistor and a coil.

An optical apparatus comprising at least two optoelectronic devices fabricated on the same substrate and in thermal communication with each other. A first optoelectronic device is configured to generate optical signals and provide them to an optical system via an optical output port. A second optoelectronic device is configured to provide heat compensation for the first optoelectronic device. An electrical circuitry provides first electrical signals to the first optoelectronic device and second electrical signals to the second optoelectronic device. The electrical circuitry is configured to adjust at least the second electrical signals to controllably adjust a temperature of the first optoelectronic device.

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.

A laser projection apparatus includes a laser source assembly, an optical engine and a projection lens. The laser source assembly includes a laser device and a combining lens group. The laser device includes a first laser-exit region emitting laser beams of first color, a second laser-exit region emitting laser beams of second color, and a third laser-exit region emitting laser beams of third color. The combining lens group includes a plurality of combining lenses and a beam spot adjustment structure. The beam spot adjustment structure is disposed in beam paths of the laser beams of first color and the laser beams of second color before being combined with the laser beams of third color, and the beam spot adjustment structure is configured to increase a divergence angle of at least one of the laser beams of first color or the laser beams of second color.

High bandwidth (e.g., > 100 GHz) modulators and methods of fabricating such are provided. An EAM comprises a waveguide mesa comprising a continuous multi-quantum well (MQW) layer; a plurality of electrode segments disposed on the waveguide mesa; and a microstrip transmission line disposed on an insulating material layer and in electrical communication with the plurality of electrode segments via conducting bridges. The waveguide mesa comprises alternating active sections and passive sections. An electrode segment of the plurality of electrodes is disposed on a respective one of the active sections. Portions of the continuous MQW layer disposed in each of the active sections having an energy gap defining an active energy gap value. Portions of the continuous MQW layer disposed in each of the passive sections having an energy gap defining an passive energy gap value. The active energy gap value is less than the passive energy gap value.

A thermally tunable laser includes: a substrate; a laser resonator, wherein the laser resonator includes a gain section, and wherein the laser resonator includes a tuning section; a heating arrangement; a heat sink arrangement for dissipating a heat flow from the laser resonator to the heat sink arrangement; and a hole arrangement for influencing the heat flow from the laser resonator to the heat sink arrangement, wherein the hole arrangement is arranged between the substrate and the heat sink arrangement, wherein one or more holes of the hole arrangement include at least one hole being arranged within a horizontal range of the tuning section, so that a thermal resistance between the tuning section and the heat sink arrangement is increased.

An embodiment provides a beam projector module including: a light source configured to output light; a substrate configured to support the light source; an optical device configured to reduce the light in terms of intensity output to a predetermined space; a frame configured to separate the optical device from the light source by a predetermined distance; an optical substrate configured to attach the optical device thereto and to define a sealed space with the substrate and the frame, the sealed space having internal pressure lower than pressure outside the sealed space; a sensor configured to measure a state of the sealed space; and a processor configured to change an operation mode of the light source depending on a measured value of the sensor.

The present disclosure discloses a regulator circuit and regulator system for a tunable laser, the regulator circuit for the tunable laser includes a control module, a digital-to-analog conversion module and a semiconductor temperature regulation module; after the regulator circuit for the tunable laser is powered on, the control module is configured to send a control signal to the digital-to-analog conversion module, the digital-to-analog conversion module is configured to convert the control signal into an analog voltage signal and send the analog voltage signal to the semiconductor temperature regulation module, the semiconductor temperature regulation module is configured to cool or heat the tunable laser according to the received analog voltage signal.

A method is for making a QCL having an InP spacer within a laser core, the QCL to provide a CW output in a high quality beam. The method may include selectively setting parameters for the QCL. The parameters may include a number of the InP spacer, a thickness for each InP spacer, a number of stages in the laser core, and a dopant concentration value in the laser core. The method may include forming the QCL based upon the parameters so that a figure of merit comprises a greatest value for a fundamental mode of operation for the QCL.