Abstract: A semiconductor laser oscillator includes a diode unit configured from a plurality of banks, in which one bank is configured from a plurality of laser diodes connected in series. The diode unit includes a wavelength locking mechanism for locking to a plurality of wavelengths. The semiconductor laser oscillator includes a controller configured to control input currents to the laser diodes of each of the plurality of banks individually in correspondence to a characteristic of a wavelength locking efficiency, and to control an output of the diode unit as a whole to a required output.

Abstract: A wavelength selective switch (WSS) may include a first port array including input ports, each to launch a respective beam of light, and a dispersive element to separate, in a lateral direction, a beam of light, launched by one of the input ports, into dispersed wavelength channel sub-beams. The WSS may include a switching array to direct the dispersed wavelength channel sub-beams, at respective angles in a vertical direction. The dispersive element may converge groups of dispersed wavelength channel sub-beams in the lateral direction to form wavelength channel sub-beams. The WSS may include a splitting element to split, in the lateral direction, a wavelength channel sub-beam, of the wavelength channel sub-beams, into split wavelength channel sub-beams. The WSS may include switching elements to direct the split wavelength channel sub-beams at respective angles in the vertical direction, and output ports associated with the switching elements.

Abstract: A semiconductor waveguide optical device and a method of manufacturing of a semiconductor optical device are disclosed. The semiconductor waveguide optical device may include a gradient index waveguide for mode conversion and/or vertical translation of optical modes of step-index waveguides, which may be disposed on or over a same substrate as the gradient index waveguide. The gradient index waveguide may be epitaxially grown.

Abstract: A free-space MCS may include an input port to launch a beam of light, N output ports, a beam splitter to split the beam of light into N portions, and a deflector array including N deflectors aligned in an array direction. Each deflector may have an active region with a size in the array direction that matches a size in the array direction of a portion, of the N portions, incident thereon. The free-space MCS may include first beam shaping optics to form a first elliptical beam spot at the beam splitter with a major axis substantially perpendicular to the switching direction, and an angle-to-offset element to direct each of the N portions from the beam splitter to a different deflector of the N deflectors. Each of the N portions may have, at the deflector, a second elliptical beam spot with a major axis substantially parallel to the switching direction.

Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.

Abstract: A method may include receiving, by a switching engine, an optical signal. The optical signal may carry a super-channel that includes a plurality of sub-carriers to be directed toward respective output ports. The switching engine may have a plurality of regions of pixels on which respective sub-carriers, of the plurality of sub-carriers, are incident. The method may include applying, by the switching engine, respective single beam steering gratings to first, overlapping, areas of the plurality of regions of pixels. The method may include applying, by the switching engine, one or more respective pluralities of beam steering gratings to second, overlapping areas of the plurality of regions of pixels. The method may include directing, based on the single beam steering gratings and the one or more pluralities of beam steering gratings, parts of the optical signal toward the respective output ports.

Abstract: An optical modulator is disclosed, in which a MMI couplers are used for input signal splitting for branching into individual Mach-Zehnder interferometers, as well as for branching and combining from individual Mach-Zehnder waveguides. MMI couplers, splitters, and combiners may be cascaded and combined with single-mode Y-splitters and combiners to provide modulators of various types, including dual polarization, quadrature phase Mach-Zehnder interferometer base optical modulators.

Abstract: An optical delivery waveguide for a material laser processing system includes a small lens at an output end of the delivery waveguide, transforming laser beam divergence inside the waveguide into a spot size after the lens. By varying the input convergence angle and/or launch angle of the laser beam launched into the waveguide, the output spot size can be continuously varied, thus enabling a continuous and real-time laser spot size adjustment on the workpiece, without having to replace the delivery waveguide or a process head. A divergence of the laser beam can also be adjusted dynamically and in concert with the spot size.

Abstract: A direct diode laser processing apparatus includes a laser oscillator including a plurality of laser diodes and emitting a multiple-wavelength laser beam, a transmission fiber transmitting the multiple-wavelength laser beam emitted from the laser oscillator, a laser processing machine collecting the multiple-wavelength laser beam transmitted through the transmission fiber and processes a workpiece, a detecting mechanism sampling part of the multiple-wavelength laser beam and detecting wavelength-by-wavelength light intensities of the sampled laser beam, a monitoring unit monitoring an output decrease in the multiple-wavelength laser beam according to a change in the wavelength-by-wavelength light intensities, and a control module controlling outputs of the plurality of laser diodes according to a monitored result from the monitoring unit. The apparatus properly monitors an output decrease in the multiple-wavelength laser beam.

Abstract: A semiconductor laser oscillator includes a diode unit configured from a plurality of banks, in which one bank is configured from a plurality of laser diodes connected in series. The diode unit includes a wavelength locking mechanism for locking to a plurality of wavelengths. The semiconductor laser oscillator includes a controller configured to control input currents to the laser diodes of each of the plurality of banks individually in correspondence to a characteristic of a wavelength locking efficiency, and to control an output of the diode unit as a whole to a required output.

Abstract: An optical device may include a semiconductor laser chip to independently generate four laser beams at different wavelengths. Each laser beam, of the four laser beams, may be directed to a respective optical output of the optical device with a sub-micron level of tolerance of each laser beam relative to the respective optical outputs of the optical device, and each laser beam, of the four laser beams, may be associated with a different optical path from the semiconductor laser chip to the respective optical output of the optical device. The optical device may include a lens to receive each of the four laser beams. The lens may be positioned to direct each laser beam, of the four laser beams, toward the respective optical output of the optical device. The optical device may include an optical isolator to receive each of the four laser beams.

Abstract: A surface emitting laser may include an isolation layer including a first center portion and a first plurality of outer portions extending from the first center portion, and a metal layer including a second center portion and a second plurality of outer portions extending from the second center portion. The metal layer may be formed on the isolation layer such that a first outer portion, of the second plurality of outer portions, is formed over one of the first plurality of outer portions. The surface emitting laser may include a passivation layer including a plurality of openings. An opening may be formed over the first outer portion. The surface emitting laser may include a plurality of oxidation trenches. An oxidation trench may be positioned at least partially between the first outer portion and a second outer portion of the second plurality of outer portions.

Abstract: A tunable transmission optical filter is optically coupled between a laser section and semiconductor optical amplifier (SOA) section of a tunable laser device. The optical filter may be tuned to provide a high transmission near the lasing peak while suppressing a significant portion of back-propagating amplified spontaneous emission (ASE) of the SOA section. Without the optical filter, the laser output spectrum may develop side lobes of higher intensity after the ASE is amplified and reflected in the forward direction by the laser gain and mirror sections. While lessening the side lobes, the optical filter simultaneously transmits the laser peak for amplification by the SOA section.

Abstract: A chip-scale package for an edge-emitting semiconductor device and a semiconductor device assembly including such a chip-scale package are provided. The chip-scale package includes an edge-emitting semiconductor device chip, a top submount disposed on a top surface of the chip, and a bottom submount disposed on a bottom surface of the chip. The top-submount area and the bottom-submount area are each greater than the chip area and less than or equal to about 1.2 times the chip area.

Abstract: The use of one or more angled or curved and diverging light pipes or reflectors placed in a light source's, e.g. diode's, emission path at appropriate distances, angles and divergence, such that a diode's emission spot size is modified and or redirected from the diode's natural emission path to alternative planes at angle to the diode's natural emission path so that a diode emission safe spot size can be achieved on any plane at angle to the original diode natural emission path at minimum distances from the diode's point of emission.

Abstract: A reflective diffraction grating and a fabrication method are provided. The reflective diffraction grating includes a substrate, a UV-absorbing layer, a grating layer having a binary surface-relief pattern formed therein, and a conforming reflective layer. Advantageously, the UV-absorbing layer absorbs light at a UV recording wavelength to minimize reflection thereof by the substrate during holographic patterning at the UV recording wavelength.

Abstract: The invention relates to a method for auto-configuring a wavelength selective switch (WSS) device having an output port and a plurality of input ports and coupled to a WSS controller. When connected to a WDM optical network, the WSS controller is programmed to utilize one or more optical channel monitors (OCM) coupled to the input and/or output ports to detect which of the wavelengths are present at the input ports. Wavelengths that are not detected on any input port are blocked by the WSS. Any wavelength detected as present at one and only one input port is switched by the WSS to the output port. If a wavelength is detected at two or more input ports, it is either blocked by the WSS at each of the input ports until user intervention, or is blocked at all but one of the input ports as defined by assigned port priorities.

Abstract: An aberration corrector and a method to reducing a spherical aberration are disclosed. The aberration corrector has a radial, rotationally symmetric variation of refractive index including a term varying in proportion to a fourth degree of a distance from the optical axis. Since the spherical aberration causes a wavefront deviation proportional to the fourth degree of distance from the optical axis, the spherical aberration can be reduced by the aberration corrector when its thickness causes the exact amount of the phase delay corresponding to the wavefront deviation, but with an opposite sign.

Abstract: Micro-electro-mechanical system (MEMS) mirror devices and manufacturing methods thereof. The device comprising a hinge layer having orthogonal tilt and roll hinges connecting inner and outer platforms such that the inner platform has bi-directional rotation. An electrode layer connected beneath the hinge layer controls rotation of the platforms. A mirror layer above the hinge layer comprises a mirror connected to the inner platform via a pedestal and fixed membrane connected to the hinge layer but detached from the mirror. An anchor temporarily reduces movement of the outer platform during fabrication. In a fabrication state, the anchor anchors the outer platform to the mirror layer's fixed membrane. In a post-fabrication state, a gap releases the outer platform.

Abstract: A spot size converter may include a tapered periodic segmented waveguide (PSW). The tapered PSW may include a plurality of waveguide segments defined by a plurality of gaps between the plurality of waveguide segments. The plurality of gaps may be at one or more angles that are not substantially parallel to a direction of a width of the tapered PSW. The direction of the width of the tapered PSW may be substantially perpendicular to a direction in which light passes through the tapered PSW.