In various embodiments, the beam parameter product and/or numerical aperture of a laser beam is adjusted utilizing a step-clad optical fiber having a central core, a first cladding, an annular core, and a second cladding.

A quantum cascade laser device includes a QCL element and a package. A light-emitting window through which laser light emitted from the QCL element passes is provided on a side wall of the package. The light-emitting window includes a small-diameter hole, a large-diameter hole larger than the small-diameter hole, a counterbore surface having an annular shape that connects the small-diameter hole and the large-diameter hole, and a window member disposed inside the large-diameter hole. An incident surface of a window member includes a first region in which an anti-reflection film is provided, and a second region metallized and formed in an annular shape to be separated from the first region and to surround the first region. The second region is joined to the counterbore surface through a solder member.

A semiconductor laser device is specified, the semiconductor laser device comprising an active layer having a main extension plane, a first cladding layer and a second cladding layer, the active layer being arranged between the first and second cladding layer in a direction perpendicular to the main extension plane, a light-outcoupling surface parallel to the main extension direction and arranged on a side of the second cladding layer opposite to the active layer, a photonic crystal layer arranged in the first cladding layer or in the second cladding layer, and an integrated optical element directly fixed to the light-outcoupling surface. Furthermore, a method for manufacturing a semiconductor laser device and a projection device are specified.

A multi-emitter laser diode device includes a carrier chip singulated from a carrier wafer. The carrier chip has a length and a width, and the width defines a first pitch. The device also includes a plurality of epitaxial mesa dice regions transferred to the carrier chip from a substrate and attached to the carrier chip at a bond region. Each of the epitaxial mesa dice regions is arranged on the carrier chip in a substantially parallel configuration and positioned at a second pitch defining the distance between adjacent epitaxial mesa dice regions. Each of the plurality of epitaxial mesa dice regions includes epitaxial material, which includes an n-type cladding region, an active region having at least one active layer region, and a p-type cladding region. The device also includes one or more laser diode stripe regions, each of which has a pair of facets forming a cavity region.

A light-emitting device includes: a substrate comprising a base; a semiconductor laser element disposed on an upper surface of the base; a sealing member located above the base and fixed to the substrate, wherein the sealing member and the substrate define a sealed space in which the semiconductor laser element is located; and a lens member fixed to the sealing member by adhesive, the lens member comprising a lens section through which light emitted from the semiconductor laser element passes. A space between the sealing member and the lens member is open to an area outside the light-emitting device.

A shared optic assembly for combined flood and dot illumination modules is disclosed. The shared optic assembly includes a first high-powered VCSEL element for providing a flood beam and a second high-powered VCSEL element for providing a dot beam, where both the first and second VCSEL elements share the same optics and are incorporated onto the same module for space savings.

A laser display system 100 is configured to increase the dynamic range of a laser diode by modulating an operating current applied to the laser diode based on a desired sequence of brightness levels and a temperature of the laser diode. In some embodiments, a measuring circuit measures a voltage of the laser diode at a given current, which indirectly indicates the temperature of the laser diode, thus obviating the need for a direct measurement of temperature. In addition, in some embodiments, the measuring circuit identifies a threshold current of the laser diode based on a range of current values at which values of the current multiplied by the derivative of the voltage against the current vary relatively rapidly. By compensating for temperature effects and identifying the threshold current, a driver of the laser diode more precisely controls light output of the laser diode across an increased dynamic range.

An external cavity diode laser has been developed to achieve a linear frequency chirp over a broad bandwidth using a silicon photonic filter chip as the external cavity. By appropriately chirping the cavity phase using the gain chip and/or a cavity phase modulator on the silicon photonic chip along with simultaneously varying the filter resonance, approximately linear frequency chirping can be accomplished for at least 50 GHz, although desirable structures with useful lesser chirp bandwidths are also described. With careful control of the chip design, it is possible to achieve predictable behavior of mode jumps along with large scannable ranges within a mode, which allows for stitching together segments of linear chirp through a mode jump to provide for very large chirp bandwidths greater than 1 THz.

Methods and devices for driving a laser diode are disclosed herein. An example method includes a boost regulator outputting a maximum boost voltage to drive a laser diode that is configured to output light within a wavelength range of 495 nanometers (nm) to 570 nm. A boost servo may measure a laser voltage, and calculate a voltage difference between the two voltages. The servo may then compare the voltage difference to a drive voltage to determine an excess voltage, and may cause the boost regulator to output an optimum voltage based on the excess voltage. The boost servo may also calculate a low voltage to drive at least one additional component that is electrically coupled to the boost regulator when the laser diode is inactive; and may cause the boost regulator to output the low voltage to power the at least one additional component.

A gallium- and nitrogen-containing laser device including an etched facet with surface treatment to improve an optical beam is disclosed.