Abstract: Methods for operating diode lasers are provided. According to one method, the diode laser comprises a wavelength selection section, a gain section and a saturable absorber. The method comprises applying a hybrid-control signal comprising a hybrid-control DC bias to the saturable absorber, and applying a hybrid-driving signal comprising a hybrid-driving DC bias and a hybrid-driving AC bias to the gain section. The hybrid signals are selected and the diode laser is configured such that a relatively high hybrid-control DC bias corresponds to a relatively low average of the output power of the diode laser, and a relatively low hybrid-control DC bias corresponds to a relatively high average of the output power of the diode laser. The hybrid-driving DC bias is between a switch-on threshold of the diode laser and a switch-off threshold of the diode laser, and the hybrid-driving AC bias is periodic.

Abstract: A method of operating a laser source comprising is provided. The method reduces speckle contrast in a projected image by creating a plurality of statistically independent speckle patterns. The method comprises generating a plurality of sub-beams that define an optical mode. The method further comprises controlling the phase of selected sub-beams to continuously sequence the laser source through a plurality of orthogonal optical modes. The plurality of orthogonal modes create a corresponding number of statistically independent speckle patterns, thus reducing speckle contrast in a image projected using the laser source by time averaging.

Abstract: A semiconductor laser device operable to emit light having a desired wavelength in the green spectral range. The semiconductor laser device may include a pumping source and a laser structure including a substrate, a first cladding layer, and one or more active region layers. The one or more active region layers include a number of quantum wells having a spontaneous emission peak wavelength that is greater than about 520 nm at a reference pumping power density. The pumping source is configured to pump each quantum well at a pumping power density such that a stimulated emission peak of each quantum well is within the green spectral range, and the number of quantum wells within the one or more active region layers is such that a net optical gain of the quantum wells is greater than a net optical loss coefficient at the desired wavelength in the green spectral range.

Abstract: A microfluidic device [10] includes at least one reactant passage [26] and one or more thermal control passages defined therein, the one or more thermal control passages being positioned and arranged within two volumes [12,14] each bordered by a wall [18,20], the walls being generally planar and parallel to one another, the reactant passage positioned between said generally planar walls and defined by said generally planar walls and walls [28] extending between said generally planar walls, wherein the reactant passage comprises multiple successive chambers [34], each such chamber including a split of the reactant passage into at least two sub-passages [36], and a joining [38] of the split passages, and a change of passage direction, of at least one of the sub-passages, of at least 90 degrees.

Abstract: A method for aligning an optical package includes applying a dither waveform and an advancement waveform to a drive mechanism. The optical package includes a semiconductor laser operable to emit an output beam with a first wavelength, a wavelength conversion device operable to convert the output beam to a second wavelength, adaptive optics configured to optically couple the output beam into a waveguide portion of an input facet of the wavelength conversion device, and a drive mechanism coupled to the adaptive optics and configured to adjust a position of the output beam. The dither waveform oscillates the adaptive optics back and forth in first and second directions to oscillate the output beam on the input facet. The advancement waveform advances the adaptive optics in an adjustment direction. Rising and falling edge times of the dither waveform are greater than rising and falling edge times of the advancement waveform.

Abstract: A microreactor assembly comprising a fluidic interconnect backbone and plurality of fluidic microstructures is provided. The fluidic microstructures are supported by respective portions of the fluidic interconnect backbone, The microreactor assembly comprises a plurality of non-polymeric interconnect seals associated with the interconnect input and output ports. The interconnect input port of the fluidic interconnect backbone is interfaced with the microchannel output port of a first fluidic microstructure at one of the non-polymeric interconnect seals. The interconnect output port of the fluidic interconnect backbone is interfaced with the microchannel input port of a second fluidic microstructure at another of the non-polymeric interconnect seals.

Abstract: Laser projection systems are provided comprising a laser source, scanning optics, beam splitting optics, and a scanning controller. According to one embodiment, the laser source is configured to produce at least two optical beams having different emission wavelength spectrums. The beam splitting optics are positioned downstream of the scanning optics and are configured to generate wavelength-dependent spatial misalignment of the two optical beams in the image plane by splitting the two optical beams into spatially misaligned propagating axes. According to another embodiment of the present invention, the beam splitting optics are positioned downstream of the scanning optics and are configured to generate polarization-dependent spatial misalignment of the two optical beams.

Abstract: The strain-managed optical waveguide assemblies of the present invention utilize a large-mode-area (LMA) optical fiber that is annealed in a first bending such that the fiber in that configuration has substantially no axial strain. A fiber support member is then used to support the annealed LMA optical fiber in a second bending configuration that forms within the LMA optical fiber an axial strain profile that reduces stimulated Brillouin scattering (SBS) as compared to the first bending configuration, and that also preferably causes the LMA optical fiber to operate in a single mode. The LMA optical fiber may have a double-clad configuration and include a doped core that serves as a gain medium. The strain-managed optical waveguide assembly can then be used to constitute a fiber amplifier that mitigates the SBS penalty associated with high-power fiber-based optical systems.

Abstract: A method for manufacturing an optical assembly comprises providing a first substrate having a first surface, providing a second substrate having a second surface facing the first surface, and forming a patterned microbump on at least a select one of the first surface and the second surface. The method further comprises applying an adhesive to the at least select one of the first surface and the second surface in a region proximate the patterned microbump, and attaching the first substrate to the second substrate by placing the first surface and the second surface in close proximity to one another such that the adhesive contacts both the first surface and the second surface, and wherein the adhesive is held within a preselected area by the patterned microbump.

Abstract: Disclosed is a method of forming a structured sintered article including providing a mixture comprising a sinterable particulate material and a binder, the binder comprising, as a function of total resin content of the binder, at least 50% by weight of a thermoplastic binder material and at least 5% by weight of a radiation-curable binder material; shaping the mixture with a mold to form a structure; setting the structure by cooling the structure or by allowing the structure to cool; separating the structure from the mold; irradiating the structure so as to at least partially cure the radiation-curable binder material, and debinding and sintering the structure so as to form a structured sintered article. Shaping may include forming a structure having one or more open channels, and sintering may include sintering in together in contact with at least one additional structure so as to cover or enclose the channels.

Abstract: The present invention relates generally to semiconductor lasers and laser projection systems. According to one embodiment of the present invention, a method of correcting output power variations in a semiconductor laser is provided. According to the method, an output power feedback loop is utilized to generate optical intensity feedback signals representing actual output power of the laser source for discrete portions V1, Vi, . . . Vj of the image signal. Error signals E1, Ei, . . . Ej are generated representing the degree to which actual projected output power varies from a target projected output power for the discrete portions V1, Vi, . . . Vj of the image signal. These error signals E1, Ei, . . . Ej are utilized to apply corrected control signals G1?, Gi?, . . . Gj? to the gain section of the semiconductor laser for projection of compatible discrete portions V1?, Vi?, . . . Vj? of the image signal.

Abstract: Single domain wafer-scale colloidal crystals and macroporous polymers are formed by dispersing concentrated solutions of colloids, desirably mondisperse silica colloids, in a viscous monomer, desirably ethoxylated trimethylolpropane triacrylate, and spin-coating them onto a substrate. Subsequent photopolymerization produces three-dimensionally ordered colloidal crystals trapped inside a polymer matrix. Selective removal of the polymer matrix, such as by oxygen plasma treatment, or removal of the silica spheres, such as by wet etching, produces large-area colloidal crystals and macroporous polymers, respectively.

Abstract: A class of designs is provided for a mixer in micro reactors where the design principle includes at least one injection zone in a continuous flow path where at least two fluids achieve initial upstream contact and an effective mixing zone (i.e. adequate flow of fluids and optimal pressure drop) containing a series of mixer elements in the path. Each mixer element is preferably designed with a chamber at each end in which an obstacle is placed (thereby reducing the typical inner dimension of the chamber) and with optional restrictions in the channel segments. The obstacles are preferably cylindrical pillars but can have any geometry within a range of dimensions and may be in series or parallel along the flow path to provide the desired flow-rate, mixing and pressure-drop. The injection zone may have two or more interfaces and may include one or more cores to control fluids before mixing.

Abstract: According to one embodiment of the present invention, a method of operating a laser source is provided. The laser source comprises a laser configured to generate an optical signal, and a polarization split and delay unit that is coupled to the optical signal. The polarization split and delay unit is configured to split the optical signal into a first and second orthogonally polarized component, create an optical path difference ?L between the first and second orthogonally polarized components and combine the first and second orthogonally polarized components into a combined signal. The method comprises modulating the optical signal by applying a wavelength modulation signal to the laser such that the modulated optical signal comprises at least a first wavelength ?1 and a second wavelength ?2, wherein the first wavelength ?1 and the second wavelength ?2 are separated by a wavelength difference ??.

Abstract: According to one embodiment of the present invention, a frequency-converted laser source is provided wherein the wavelength conversion device comprises a plurality of waveguide components comprising respective input faces positioned in an effective focal field of the laser source. Individual ones of the waveguide components contribute different elements to a set of distinct wavelength conversion properties, defining a set of distinct wavelength conversion properties attributable to the waveguide components. The set of distinct wavelength conversion properties comprises properties representing phase matching wavelengths of the waveguide components, spectral widths of the waveguide components, conversion efficiency of the waveguide components, or combinations thereof. Additional embodiments are disclosed and claimed.

Abstract: Glass, glass compositions, methods of preparing the glass compositions, microfluidic devices that include the glass composition, and methods of fabricating microfluidic devices that include the glass composition are disclosed. The borosilicate glass composition includes silicon dioxide (SiO2) in a range from about 60% to 74% by total composition weight; boric oxide (B2O3) in a range from about 9% to 25% by total composition weight; aluminum oxide (Al2O3) in a range from about 7% to 17% by total composition weight; and at least one alkali oxide in a range from about 2% to 7% by total composition weight. In addition, the borosilicate glass has a coefficient of thermal expansion (CTE) that is in a range between about 30×10?7/° C. and 55×10?7/° C. Furthermore, the borosilicate glass composition resists devitrification upon sintering without the addition of an inhibitor oxide.

Abstract: A magnetic photonic crystal for providing asymmetry of spatial frequencies in the propagation of light is provided. The crystal is formed from at least two materials having different indices of refraction which are aligned along the longitudinal axis of the crystal. And arranged in an array whose symmetry does not include a spatial inversion operator such that (x,y)==/=(?x,?y). One or more of the materials forming the array is magnetic such that the magnetic group representation of the array does not include time inversion as a symmetric operator. In operation, when the magnetic material forming the material is magnetized, the group velocity property of light propagated in one direction along the axis of the array is different from the group velocity property of light transmitted in an opposite direction through the array. The magnetic photonic crystal may be used, for example, as an optical memory device or a high speed modulator/demodulator.

Abstract: A method for generating a linear single-polarization output beam comprises providing an optically active linearly birefringent and linearly dichroic fiber for propagating light and having a single polarization wavelength range and a gain bandwidth; optically pumping the optically active linearly birefringent and linearly dichroic fiber for obtaining fluorescence within the gain bandwidth; and aligning the single-polarization wavelength range to overlap a desired spectral region of the gain profile.

Abstract: Glass-based micropositioning systems and methods are disclosed. The micropositioning systems and methods utilize microbumps (40) formed in a glass substrate (12 or 100). The microbumps are formed by subjecting a portion of the glass substrate to localized heating, which results in local rapid expansion of glass where the heat was applied. The height and shape of the microbumps depend on the type of glass substrate and the amount and form of heat delivered to the substrate. The microbumps allow for active or passive micropositioning of optical elements, including planar waveguides and optical fibers. Optical assemblies formed using microbump micropositioners are also disclosed.

Abstract: A method and apparatus for secure distribution of cryptographic key information based on quantum cryptography is described. The apparatus incorporates or is used with a transmitter comprising a source of pairs of dim, depolarized light pulses together with a phase modulator and random number generator that are used to encode the pulse pairs with the binary key information by changing the relative phases of the pulses of some pairs. The apparatus incorporates a receiver comprising a polarization beam splitter, and a pair of interferometers and optical detectors. The invention overcomes problems associated with polarization evolution in quantum cryptography systems that incorporate a non-polarization-preserving optical channel (e.g. standard optical fiber).