Abstract: A method and apparatus for reducing speckle in a laser illumination system uses a despeckle device including an optical retarder providing an odd integer multiple of substantially half-wave retardation for light emitted from a coherent laser in the laser illumination system. The near half-wave optical retarder has a substantially constant retardance and a spatially varied slow axis. The spatially varied slow axis imposes a phase mask on the beam of light, which provides sub-resolution optical phase modulation to a resolution spot on the detector. The near half-wave optical retarder is actuated mechanically or electrically to vary the sub-resolution optical phase modulation within an integration time of the detector.

Abstract: Raman tilt is induced by the propagation of optical signals in optical communication fibers during and after transient events. Certain characteristics of the light are monitored at each amplification node and Raman tilt correction is achieved by spectral tilt control optics. The light is monitored either as total power, and/or the power of light after passing through one or more optical filters. In the case of EDFA (Erbium Doped Fiber Amplifier) the correction is performed by adjusting stage gains and VOA loss distribution within the amplifier. The light detection is relatively fast, whereby the tilt is compensated by fast controlled VOA and pump power adjustment during a transient event.

Abstract: The invention relates to an asymmetric Mach Zehnder Interferometer (MZI) having a reduced drive voltage, coupled to a compact low-loss arrayed waveguide grating (AWG) to provide a broader passband with low ripple. The integrated device has a compact stackable design for improved manufacturing yield. Inputs and outputs of the device are disposed in alignment on opposite sides of a silicon chip with the MZI having an opposite curvature to the AWG. To achieve this alignment, waveguide arms of the MZI are crossed without coupling between them before the optical signal is combined and coupled into the AWG.

Abstract: The present invention provides an electro-optic device comprising three or more radio-frequency (RF) signal electrodes, which each include an input segment. The input segments of the three or more RF-signal electrodes are arranged in a fractal pattern followed in an RF-signal transit direction by a parallel-bend pattern. Advantageously, this arrangement allows matching of RF-signal transit times of the input segments and near matching of RF-signal losses of the input segments.

Abstract: The invention relates to a method of reducing vertical divergence of a high-power semiconductor laser with a negligible threshold current and conversion efficiency penalty. The low divergence is achieved by increasing the thickness of the n-cladding layer in an asymmetric laser diode stack structure, to a value ranging from 1 to 4 times the laser mode size measured at 10% level. The divergence may be tuned by adjusting the n-cladding layer parameters in an area of the tail the optical mode, measuring 0.03% or less of the maximal optical power density of said optical mode.

Abstract: The invention relates to an external optical modulator comprising a Mach-Zehnder having a signal electrode including at least four sections of unequal length to one another positioned over an alternating domain structure in an electrooptic substrate, and including a center section, or center pair of sections disposed asymmetrically between pairs surrounding sections. The surrounding pairs, comprise the two sections adjacent the center section or pair of sections, and each two sections adjacent the previous pair of sections, moving outwardly from the center to the final outermost pair, L1 and LN at the RF input 2 and RF output 4. In each pair, the section lengths are equal, or the section closer to the RF output 4 has a longer length than the section closer to the RF input 2. The surrounding pairs have lengths that decrease from the innermost pair to the outermost pair. For a zero chirp structure, the section lengths are selected to maintain an equivalent length for the inverted and uninverted domain sections.

Abstract: A micro-array of optical vortex retarders is provided by forming an alignment layer having a plurality of discrete alignment patches with different orientations. A layer of birefringent material, including one of a liquid crystal and a liquid crystal polymer precursor material, is provided adjacent to the alignment layer. The aligning orientation and position of each discrete alignment patch in the plurality of discrete alignment patches is selected to induce the layer of birefringent material to form at least one optical vortex retarder adjacent to a substantially non-oriented region of the alignment layer.

Abstract: A non-conductive carrier having a conductive component comprising a plurality of sections to disrupt the conductive component's conductive path. Each section is isolated from other sections such that a charge accumulated in one section cannot combine with the charge accumulated in another section, thereby minimizing any potential electrostatic discharge from the carrier.

Abstract: An optical device exhibiting a color shift upon rotation is disclosed. The optical device has a textured surface having a relief structure finer than a human eye resolution but large enough not to exhibit diffraction effects. The textured surface is coated with an interference thin film that exhibits a color shift with tilt. A uniform color seen at one angle of rotation changes to another uniform color when the optical device is rotated in its own plane. A method of manufacturing of such an optical device, as well as the use of the optical device as an optical security and authentication element, is also disclosed.

Abstract: The invention relates to multiport routing devices for routing optical signals which also provide beam attenuation by imparting a controllable offset between an optical beam and a selected optical port. A multiport optical routing device of the present invention has a plurality of non-equally spaced optical ports disposed in a row to enable beam offset for attenuation without substantially increasing optical crosstalk between adjacent ports in a compact port arrangement.

Abstract: A two-step method of making of a security printed image is disclosed and includes coating of the surface of a substrate with a predetermined image shape with an ink containing flaked magnetic pigment in a predetermined concentration, exposing a wet printed image to a magnetic field to align magnetic particles in a predetermined manner, allowing the ink to cure, and coating the substrate with a second printed image on the top of the first image. The second printed image with the same or different image shape is printed with another ink containing clear or dyed ink vehicle mixed with flaked magnetic pigment in a low concentration, exposed to the magnetic field of the same or different configuration as the first printed image and cured until the ink is dry.

Abstract: A network diagnostic device or component such as a network analyzer or a jammer that is placed in-line between two nodes in a network to perform a flow control operation transparently without the requirement of a separate link layer implementation. The network diagnostic device may include a diagnostic module configured to perform network analyzer operations, a memory a first flow control module a second flow control module. In some embodiments, when performing the flow control operation, various modules and/or components may cause the network diagnostic device to enter a first pass-through mode and to then enter into a first flow control handshaking mode from the first pass-through mode. The various modules and/or components may also cause the network diagnostic device to enter a second pass-through mode from the first flow control handshaking mode and to then enter into a second flow control handshaking mode from the first pass-through mode.

Abstract: The invention relates to a method of electronic contrast enhancement for an LCD panel for use in an imaging device. The method comprises the step of coupling the LCD panel with a trim retarder in a pre-determined azimuthal orientation for at least partially compensating the residual in-plane retardance, followed by the step of non-mechanical fine-tuning of a dark state of the LCD panel. In the preferred embodiment, the fine-tuning of the dark state of the LCD panel is realized by adjusting the dark-state magnitude of the LC voltage. The method can be used in batch, e.g. wafer-level manufacturing of integrated trim retarder/LCD panels assemblies that can be electronically tuned to provide high on/off contrast.

Abstract: The invention provides a method of reducing a time-averaged coherence of laser radiation for current-tunable lasers, and a laser apparatus realizing the method, by modulating the laser drive current using a modulation function optimized for obtaining a pre-determined time-averaged spectral profile of the laser radiation. In a preferred embodiment, the pre-determined time-averaged spectral profile has a substantially Gaussian shape. The method is described in reference to laser diodes.

Abstract: An apparatus for coupling radiation of individual laser diode emitters into a common optical fiber is disclosed. The radiation is collimated along fast axis and combined by using crossed pairs of flat mirrors. The combined beams are collimated by a common slow axis collimating lens. The laser diode emitters are disposed on both sides of an optical axis of the slow axis collimating lens such that the optical path lengths from the emitters to the slow axis collimating lens are equal.

Abstract: An optical structure includes a light transmissive substrate having a surface relief pattern applied thereon, such as a hologram. One or more layers can be patterned corresponding to materials playing the role of absorbers or reflectors on a Fabry-Perot type of optical structure. These materials are applied over portions of the surface relief pattern so as to form alphanumeric characters, bars codes, or pictorial or graphical designs. Additional layers may be applied to the patterned layer of the reflective or absorber materials and exposed portions of the surface relief pattern in order to provide desirable optical effects to the exposed portions of the surface relief pattern. In some embodiments, the optically active coating is a color shifting thin film, or contains color shifting flakes based on Fabry Perot designs.

Abstract: The invention relates to RF termination for reducing electrical signal reflections at the end of transmission line electrodes on an electro-optical (EO) optical modulator. The disclosed termination incorporates a RF tap which permits the monitoring of the RF power and reflection conditions at the EO modulator. The integrated termination/tap can also be integrated with detection circuitry, such as RF diodes and passive components, giving improved performance, lower cost manufacturability as well as a more compact and efficient package.

Abstract: A method of planarizing a plurality of orientable non-spherical flakes supported by a longitudinal web is disclosed. A web supporting a coating of field orientable non-spherical flakes is placed between magnets so that the fields from the magnets traverse the web. First and third magnets are provided on one side of a feedpath and a second magnet is provided between the first and third magnets on the other side of the feedpath.

Abstract: A contrast compensator for improving the panel contrast of liquid crystal (LC) microdisplays having a high-order waveplate configured as an O-plate and supporting a thin film transistor layer is provided. The contrast compensator includes a counter high-order waveplate configured as an O-plate, which has a birefringence opposite in sign to a birefringence of the thin film transistor substrate.

Abstract: Pluggable fiber optic modules having a receive printed circuit board and a transmit printed circuit board perpendicular with an interface printed circuit board with an edge connection. The edge connection of the interface printed circuit board to plug into and out from an edge connector of a host printed circuit board. A transmitter optoelectronic device is coupled to the transmit printed circuit board. A receiver optoelectronic device is coupled to the receive printed circuit board. The pluggable fiber optic modules may further include a support base, a nose receptacle, and an alignment plate.