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.

A semiconductor laser diode includes multiple layers stacked along a first direction, in which the multiple layers include: a first multiple of semiconductor layers; an optical waveguide on the first multiple of semiconductor layers, in which the optical waveguide includes a semiconductor active region for generating laser light, and in which the optical waveguide defines a resonant cavity having an optical axis; and a second multiple of semiconductor layers on the optical waveguide region, in which a resistivity profile of at least one layer of the multiple layers varies gradually between a maximum resistivity and a minimum resistivity along a second direction extending orthogonal to the first direction, in which a distance between the maximum resistivity and the minimum resistivity is greater than at least about 2 microns.

Methods for driving a tunable laser with integrated tuning elements are disclosed. The methods can include modulating the tuning current and laser injection current such that the laser emission wavelength and output power are independently controllable. In some examples, the tuning current and laser injection current are modulated simultaneously and a wider tuning range can result. In some examples, one or both of these currents is sinusoidally modulated. In some examples, a constant output power can be achieved while tuning the emission wavelength. In some examples, the output power and tuning can follow a linear relationship. In some examples, injection current and tuning element drive waveforms necessary to achieve targeted output power and tuning waveforms can be achieved through optimization based on goodness of fit values between the targeted and actual output power and tuning waveforms.

One embodiment may provide a light source module including: a light source part including at least one vertical cavity surface-emitting laser, which is configured to transfer light through N (N being a natural number equal to or greater than 1) apertures; at least one collimator lens through which light emitted from the light source part passes; and a driving device configured to make the collimator lens move, wherein the at least one vertical cavity surface-emitting laser comprises divided regions, and an intensity of a beam is controlled according to a predetermined far-distance mode or near-distance mode.

A coating having a mismatched coefficient of thermal expansion is applied to an underlying light emitting diode (LED) or laser diode (LD), such that as the temperature of the device changes, a varying level of strain is introduced to the underlying LED or LD. Because strain can also adjust the effective bandgap energy (and hence emission wavelength) of the device, the external strain-inducing coating can act to either compensate for the wavelength shift due to temperature (resulting in reduced d/dT) or accentuate it (resulting in increased d/dT). By proper selection of coating material and geometry, full control over d/dT can be achieved.

The present invention relates to a laser sensor for self-mixing interferometry. The laser sensor comprises at least one semiconductor laser light source emitting laser radiation and at least one photodetector (6) monitoring the laser radiation of the laser light source. The laser light source is a VECSEL having a gain medium (3) arranged in a layer structure (15) on a front side of a first end mirror (4), said first end mirror (4) forming an external cavity with an external second end mirror (5). The proposed laser sensor provides an increased detection range and can be manufactured in a low-cost production process.

Described are various configurations of integrated wavelength lockers including asymmetric Mach-Zehnder interferometers (AMZIs) and associated detectors. Various embodiments provide improved wavelength-locking accuracy by using an active tuning element in the AMZI to achieve an operational position with high locking sensitivity, a coherent receiver to reduce the frequency-dependence of the locking sensitivity, and/or a temperature sensor and/or strain gauge to computationally correct for the effect of temperature or strain changes.

In various embodiments, monitoring of one or more secondary diffracted beams formed within a laser resonator provides information based at least in part on which a primary diffracted beam formed within the laser resonator is controlled.

A design and method for introducing asymmetric crystal strain to control polarization in a tunable VCSEL, either optically or electrically pumped. The invention is especially relevant to wafer- or die-bonded tunable VCSELs. Then, mechanical stress is applied to the half VCSEL device by asymmetric arrangement of metal bond pads.

An atomic oscillator includes a semiconductor laser, an atomic cell, a light receiving element, a first temperature control element, and a second temperature control element. The semiconductor laser includes a first mirror layer, a second mirror layer, and an active layer disposed between the first mirror layer, the second mirror layer, and a heat transfer member disposed on the second mirror layer. The atomic cell is irradiated with light emitted from the semiconductor laser. In the atomic cell, an alkali metal atom is accommodated. The light receiving element detects intensity of light transmitted through the atomic cell and outputs a detection signal. The first temperature control element controls a temperature of the semiconductor laser. The second temperature control element is controlled based on the detection signal and is connected to the heat transfer member.