Abstract: An optical deflection device includes an optical deflection element having a pair of transparent boards arranged in a mutually opposing manner. A liquid crystal layer is filled between the boards and forms a chiral smectic C phase. An orientation film orients liquid crystal molecules in the liquid crystal layer in a substantially perpendicular direction with respect to the liquid crystal layer. Electrodes generate an electric field in a substantially parallel direction with respect to the liquid crystal layer. A first voltage application part applies, to the electrodes, an ac voltage of a deflection frequency switching the optical deflection direction of the optical deflection element. A second voltage application part applies, to the electrodes, an ac voltage of a higher frequency than the deflection frequency.

Abstract: A Mach-Zehnder optical waveguide is disposed in a substrate made of a material having an electro-optic effect. Coplanar-waveguide modulating electrodes are disposed on a principal surface of the substrate. A dielectric layer is disposed on a reverse surface of the substrate. A supporting substrate having a recess is disposed in contact with the dielectric layer such that the recess is located at a position corresponding to a modulating region. The relationship: ?r>?s is satisfied where ?r represents the dielectric constant of the supporting substrate and ?s represents the dielectric constant of the dielectric constant of solid, liquid, or gaseous substance in the recess.

Abstract: Provided is an electro-optic reflective modulator comprising a reflective active material, preferably comprising a reflective organic free radical compound, that reflects a wavelength in a highly reflective state and is reversibly switched to a transparent and low reflectivity state at the wavelength by the application of an electric current. Preferably, the electro-reflective optical modulator is solid state with no moving parts such that the active material does not move when reversibly switched between the high and low reflective states. Also provided are methods of modulating an optical signal utilizing such electro-optic reflective modulators.

Abstract: The invention refers to electrically controlled optical switching devices which are based on the use of a layer of dielectric and transparent viscoelastic material (G) located between transparent first (ES1) and transparent second (ES2) electrode structures. According to the invention, the first (ES1) and second (ES2) electrode structures are arranged in a manner that the thickness of the layer of the viscoelastic material (G) can be electrically altered maintaining the thickness of said layer substantially equal. This makes it possible to realize a generic, electrically controlled variable thickness plate (30). The generic variable thickness plate (30) can be further used to create optical switching devices based on a Fabry Perot Interferometer or a Mach-Zehnder Interferometer.

Abstract: The present invention provides an optical switch having a photonic crystal structure. An optical switch of the invention has a slab optical waveguide structure whose core (35) has a two-dimensional photonic crystal structure where two or more media (33, 34) with different refractive indices are alternately and regularly arranged in a two-dimensional manner. The photonic crystal structure comprises: a line-defect waveguide; and means for altering the refractive index of the line-defect waveguide.

Abstract: A photonic device including an array of lasers providing light to an array of electro-absorption modulators, both on a common substrate. In some embodiments the lasers are in a closely spaced array and lase at different wavelengths, providing with associated electro-absorption modulators a compact wavelength selectable laser.

Abstract: An optical switch, optical switching method, and a switched optical communication system include at least one micro-mirror in a path along which an optical signal propagates between first and second optical waveguides. Further provided is a refractive material through which the optical signal propagates. The refractive material has a refractive index greater than the refractive index of air. The refractive index of the refractive index may be less than or equal to a refractive index of the optical waveguides.

Abstract: An optical device is capable of changing signal light to a plurality of paths. The device includes a film, a heating source attached to the film, and a heat radiator plate attached to the other portion of the film. The refractive index of the film varies according to heat excitation, and the film comprises crystal grains of an oxide and amorphous portions present between the crystal grains.

Abstract: An optical steering method and apparatus. In one aspect of the present invention, the disclosed apparatus includes a multi-mode interference (MMI) device disposed in a semiconductor substrate. The MMI device includes an input and a plurality of outputs. Each one of the plurality of outputs of the MMI device is optically coupled to the input of the MMI device. A phase array is disposed in the semiconductor substrate. The phase array includes a plurality of inputs and a plurality of outputs. The plurality of inputs of the phase array optically are coupled to the plurality of outputs of the phase array. The phase array is coupled to control relative phase differences between optical beams output by each one of the plurality of outputs of the phase array.

Abstract: Numerous novel structures and methods are presented for their ability to correct angular and offset alignment errors caused by thermal distortion of a device formed out of dissimilar materials, such as a movable platform and waveguide coupled to a fixed platform and another waveguide. A flexure connected between two platforms corrects offset alignment errors along the centerline axis of the flexure. Thermal distortion is corrected also by varying the relative size of the two platforms and the addition of slots and/or extraneous waveguides. A waveguide may be sandwiched between two matching materials, with or without an extra thermal compensation layer portion. A method uses simple processes to build a substrate with matching waveguides on each side of the substrate. Another simple method creates a suspended structure by using simple semiconductor processes.

Abstract: An optical mirror module has an interface port that is spaced from a corresponding die. More specifically, the optical mirror module includes a substrate and a die having at least one mirror and circuitry to control the at least one mirror. The optical mirror module defines a plane that is substantially parallel to the die. The optical mirror module further includes the noted interface port, which is adapted to electrically couple the circuitry with a device external to the optical mirror module. As suggested above, the interface port is located on the substrate and spaced from the die on the plane.

Abstract: It is an object of the invention to provide a network topology for OCDM signals. Coding splitters combining both coding and splitting functions are provided. The coding splitters themselves can be made from cascaded Mach Zehnder filters which are located somewhere in the network and which can be integrated using planar waveguide technologies. Each OCDM transceiver as well as the network is connected to the splitter via a pair of fibers for the two transmission directions. This set-up has the advantage that the same splitter can be used for both directions to and from the transceivers on one side and to and from the network on the other side.

Abstract: Optical switch packaging techniques and optical switch components are described. In one aspect, an optical switch component that includes a die mounted on an interposer is described. The die has an exposed array of mirrors that can be used as part of an optical switch. Typically, the interposer will also have a fiber array mount arranged to receive a fiber bundle and to position the fiber bundle appropriately over the array of mirrors. In some embodiments, an optical switch can be formed by putting together two mirror image interposer based optical switch components. When placing two interposer based optical switch components together, an alignment frame may be positioned between the interposers to help maintain a desired spacing between the respective arrays of mirrors. In some such embodiments, an inner housing is provided that encloses the dice, the fiber array mounts the alignment frame and portions of the interposers, but leaves connectors mounted on the interposers exposed.

Abstract: A waveguide having a periodic structure and the excitation of exciton polariton as one form of interactions between radiation fields and matter systems are applied to light switching to provide an optical switch that is excellent in light intensity extinction ratio and operable at a speed in the terahertz order. The optical switch includes a polariton and photon interacting region (5) made of a grating (3) formed on a top face of a transparent substrate (2) and a semiconductor layer (4) with which the grating (3) is covered. The polariton and photon interacting region (5) is irradiated from a free space with a controllable light (7) having a preestablished wavelength and also from a free space with a control light (6) having a preselected wavelength to control the transmissivity of the controllable light (7) through the polariton and photon interacting region (5).

Abstract: An improved and lower cost color spectrophotometer, especially suitable for an on-line color printer color control system, in which plural different spectra LEDs sequentially perpendicularly illuminate a common and substantially circularly illuminated color test area, which may be variably spaced and variably oriented relative to the spectrophotometer, through a common central lens system, and also the reflected illumination therefrom may be measured at 45 degrees thereto by averaging the outputs of photodetectors spaced around that circularly illuminated color test area, to provide reduced sensitivity to the variable angular or azimuthal orientation of the color test area relative to the spectrophotometer, and which photodetectors may be so illuminated by 1:1 optics for spatial insensitivity.

Abstract: An optical switch for an optical network, which can switch a light beam from and input fiber to an output fiber quickly and without expensive intermediate conversions to electrical form. The optical switch changes the relative phase of the individual portions of a cross section of a wave front of a beam using wave front interference and can be used in packet switching with switching speeds of about 10 nanoseconds. These optical switches use a phase spatial light modulators (PSLM) that include an array of phase shifting elements preferably of Gires-Tournois interferometers. Each of the phase shifting elements has either a stationary reflective surface with a movable reflective surface or an electro-refractive medium sandwiched between two stationary surfaces. In the first embodiment, the stationary reflective surface with a movable reflective surface is kept a known distance apart by applied potential.

Abstract: A non-linear optical material comprising crystal grains of an oxide having a corundum type crystal structure, and amorphous portions in the surroundings of the crystal grains, in a thin film, is disclosed. The non-linear optical thin film has such a property that its refractive index varies largely when energy is applied thereto. Since the material shows little loss of light transmitted therethrough, it is possible, by use of the material, to provide a non-linear optical device for efficiently changing over the emission path of a light signal or turning-ON/OFF the light signal.

Abstract: Disclosed is an optical switch using V-beam electrothermal actuators, buckle beam springs, and movement translation mechanism with its bi-directional movable latched function for optical communication applications. In the preferred embodiments, various layout combinations of the V-beam electrothermal actuators, the buckle beam springs, a reflective mirror shutter connected to a shutter beam, and spatial joint to enable various operation approaches to realize the bi-stable switching function without external electrical load and electrical power consumption of said optical switch regarding the input optical signals transmitting toward the output channels, or the input optical signals transmitting forward to the reflective mirror shutter and then being reflected toward the output channel.

Abstract: An optical switch is fabricated using micro-electro-mechanical system (“MEMS”) techniques. A thin mirror is fabricated in the major plane of the substrate and rotates about an axis perpendicular to the major plane to move into and out of an optical beam path. The mirror surface is open for chemical polishing and deposition, resulting in a high-quality mirror. In one embodiment, the backside of the mirror is patterned with reinforcing ribs. In another embodiment, a two-sided mirror is fabricated.

Abstract: The present invention is directed to an optical space switch accommodating a plurality of input light paths and output light paths. The optical space switch comprises a plurality of polarization control optical switches, each consisting essentially of: polarization control means having elements, one for each input light path, for rotating through 90° the polarizing direction of light information incident from each input light path or otherwise retaining the polarizing direction thereof for output; and a light path routing element for routing the light path for the light information output from the polarization control means in accordance with the polarizing direction of the light information. These polarization control optical switches are arranged in a matrix pattern or coupled in cascade to implement a polarization control optical space switch.

Abstract: A switching array comprising a plurality of total internal reflection (TIR) switches can be used to direct optical signals from any one of a plurality of input optical fibers to any one of a plurality of output optical fibers. Free space regions exist between the input optical fibers, the switches, and the output optical fibers. Accordingly, the light from an input optical fiber to an output optical fiber travels through the TIR switch array largely, if not entirely, in free space mode. To provide efficient coupling of light from the input optical fibers to the plurality of switches and ultimately to the output optical fibers, collimators and other coupling elements are employed. Preferably, the collimators have a Rayleigh range longer than the path length that the light will travel from the respective input optical fiber to the respective output optical fiber.

Abstract: A coplanar integrated optical waveguide electro-optical modulator comprises a substrate (1) of an electro-optic material, at least two optical waveguides (41, 42) integrated in the substrate in correspondence of a surface (71) thereof, and an electrode system (80, 90, 100; 80, 90, 900; 12-15; 120, 130, 140, 150, 160, 170) arranged on the surface for applying a modulating electric field to the waveguides suitable for causing a modulation of a refractive index of the two waveguides in a device modulation region (50). The waveguides are formed, for at least a section thereof (411, 421) in the device modulation region, in respective substrate regions (61, 62) which have electro-optic coefficients of opposite sign along an axis transversal to the waveguide sections, so that a modulating electric field of same direction and orientation in the waveguide sections causes refractive index modulations of opposite sign in the waveguide sections.

Abstract: The present invention provides improved optical switches in which no mechanical movement is required to direct optical pathways between plural fiber ports. Advantageously, the inventive switches incorporate two-stage polarization rotation to improve isolation depth, as well as temperature and wavelength independence. The inventive switches also incorporate light bending devices to allow two fibers to be coupled to the light beams using a single lens achieving small beam separation for compactness. In the inventive switch, an optical signal is spatially split into two polarized beams by a birefringent element, which passes through a polarization rotation device that comprises waveplates, walk-off elements, and electrically controllable polarization rotators, and recombine into an output fiber, achieving polarization independent operation.

Abstract: A quasi-optical system is provided. More specifically, a quasi-optical system is provided comprising various embodiments of quasi-optical grids (such as arrays or layers and the like) with reconfigurable quasi-optical unit cells. The quasi-optical system, grids and unit cells are configured to control an incident beam in a variety of ways.

Abstract: An optical system includes a layer of magneto rheological (MR) fluid having a surface exposed to air or vacuum. The MR fluid has a first state wherein the surface is reflective, and a second state wherein the surface is non-reflective. A magnetic actuator selectively applies a magnetic field to the MR fluid to actuate the fluid to the second state.

Abstract: The present invention provides an electro-optic ceramic material including lead, zinc and niobium having a propagation loss of less than about 3 dB/cm and a quadratic electro-optic coefficient of greater than about 1×10−6 m2/V2 at 20° C. at a wavelength of 1550 nm. The present invention also provides electro-optic devices including an electro-optic ceramic material including lead, zinc and niobium having a propagation loss of less than about 3 dB/cm and a quadratic electro-optic coefficient of greater than about 1×10−16 m2 V at 20° C. at a wavelength of 1550 nm. The materials and devices of the present invention are useful in optical communications applications such as intensity and phase modulation, switching, and polarization control.

Abstract: An electrooptical deflector is presented. The electrooptical deflector includes a material that has a different refractive index for different polarization states and changes its refractive index in response to voltage (e.g., lithium niobate or lithium tantalite). Inside the material is a poled region that includes triangularly-shaped prisms, each of which affects the direction in which an incident light beam propagates. When a light beam of a known polarization state propagates through the material, its direction of propagation (i.e., the amount of deflection) is controlled by a voltage applied to the poled region and the size and number of the prisms in the material.

Abstract: A reflective spatial light modulator (SLM) includes a first substrate, a second substrate and an electro-optic material positioned between the first and second substrates. The first substrate includes a reflective ground layer that acts as a continuous first electrode and the second substrate includes a pixel layer having a plurality of pixel elements formed in a pattern. The pixel elements are formed of a transparent conductive material and are separated by inter-pixel regions formed of a non-conductive material. A transmissivity of the electro-optic material in a vicinity of each of the plurality of pixel elements is controlled by a potential difference applied between the first electrode and a respective one of the pixel elements.

Abstract: An optical switch for switching an incoming light signal to one of a number of output ports in a polarization independent manner. The optical switch includes a walk-off device, and a compensator which compensates for walk-off distance variations of two polarized beams, with orthogonal polarization directions, associated with the walk-off device.

Abstract: The invention specifies a method and apparatus for optical polarization control which enable non-ideal component behavior to be corrected by means of a calibration table. This ensures shorter constructional length, lower operating voltages or higher level functions (ER instead of GSBA).

Abstract: A light shutter device including a group of light shutter elements 31a, 31b 31c and 31d formed on a light shutter chip 30 made of PLZT has a construction in which an electrode gap is set wider in a element in which an electric field acts more strongly to equalize half wavelength voltages of elements almost to the same level since electric fields acting on the elements are different in strength from each other even under a prescribed voltage applied between a common electrode 32 and each of individual electrodes 33. An electrode gap of an element 31c having a weaker electric field is comparatively set narrower, whereas an electrode gap of an element 31d having a stronger electric field is set comparatively wider. Moreover, a shape of electrodes of each element are altered so as to make half wavelength voltages of elements almost equal.

Abstract: An aspect of an electromagnetic energy wave is altered by disposing in its propagation path a material that changes optical properties in response to an acceleration force.

Abstract: A matrix display (20) comprises pixels based on switching elements (30) which comprise a switchable layer which can be switched from one chemical state to another, the optical properties of said chemical states being different. Voltage-limiting devices (41, 42) preventing pixel degradation are arranged on the switching elements (30).

Abstract: A sheet-like display medium includes a switching layer containing a switching material having a light absorption spectrum which changes in a visible light range when a voltage no less than a threshold value is applied while also maintaining the changed light absorption spectrum even after the voltage application is interrupted, and an electrode layer laminated on the switching layer. The switching material may be an organic metal complex such as Cu-TCNQ or Ag-TCNQ.

Abstract: A controllable phase plate has numerous domains that are randomized as to the orientation of their birefringence and can be used in a power limiting control to produces an electrically controllable diffraction pattern having a portion, especially the zero mode axial spot of the pattern, that is directed onto an output aperture such as a pinhole or an optical fiber end. Controlling the phase plate produces an interference peak or null (or an intermediate level) of light, coupled into the output aperture. The phase plate preferably comprises a liquid crystal with controllable birefringence. The domains have paired orthogonal orientations, which is a condition that is met in randomized domains. The paired orthogonal orientations make the device polarization insensitive. In a controllable attenuating device, collimating lenses are placed before and after the phase plate along a beam path to focus a clear interference pattern on a screen containing the output aperture.

Abstract: An optical mirror module has an interface port that is spaced from a corresponding die. More specifically, the optical mirror module includes a substrate and a die having at least one mirror and circuitry to control the at least one mirror. The optical mirror module defines a plane that is substantially parallel to the die. The optical mirror module further includes the noted interface port, which is adapted to electrically couple the circuitry with a device external to the optical mirror module. As suggested above, the interface port is located on the substrate and spaced from the die on the plane.

Abstract: An optical switch comprising two segments at least partially separated by a surface that is partially reflective and partially transmissive to the optical signals being switched, each segment having at least one optical input and at least one optical output, the segments being arranged such that an optical signal can be switched from said input to said output by reflection from said surface, with the optical signal that is generated by transmission through said surface being directed to an output of the other segment.

Abstract: In order to provide a small-sized and compact optical switch of 1×4 type. Two movable optical fibers are fixed on a substrate by a fixing block disposed in a middle portion of the fibers. Two movable blocks made of a soft magnetic body are mounted to the both ends of the movable optical fibers. Two soft magnetic fixing blocks are arranged on the substrate for fixing one optical fiber so as to oppose to one of the movable block, and for fixing four optical fibers so as to oppose to the movable block, respectively. Two movable blocks can be independently moved with respect to the respective fixing blocks by means of actuators. Further, it is possible to detect a position of each movable block with respect to the fixing block by means of detecting electrodes.

Abstract: The present invention provides improved optical switches in which no mechanical movement is required to direct optical pathways between plural fiber ports and light transmission is bi-directional. Advantageously, the inventive switches permit bi-directional light transmission. The inventive switches also incorporate light bending devices to allow two fibers to be coupled to the light beams using a single lens for compactness. In the inventive switch, an optical signal is spatially split into two polarized beams by a birefringent element, which passes through a polarization rotation device that comprises waveplates, walk-off elements, and an electrically controllable polarization rotator, and recombine into an output fiber, achieving polarization independent operation. The switches of the present invention rely on electro-magnetically or electro-optically switching the beam polarizations from one state to another to rapidly direct the light path.

Abstract: A display includes a light source and a filter positioned to receive light from the light source. An electronically controlled mirror can direct light through the filter in a first mode of operation and not through the filter in a second mode of operation. The display can be utilized in an avionics display system with night vision equipment. The electronically controlled mirror can be a reversible electrochemical mirror (REM).

Abstract: An optical switching device contains an active stage coupled to a passive stage. The index of refraction in the active stage is variable to change the entry direction of a light beam into the passive stage, which has a fixed index of refraction. Because the light beam can enter the passive stage at different angles, the exit direction of the light beam from the passive stage can be changed. The resulting optical switch allows switching without any mechanical components.

Abstract: It is an object of the invention to provide a network topology for OCDM signals. Coding splitters combining both coding and splitting functions are provided. The coding splitters themselves can be made from cascaded Mach Zehnder filters which are located somewhere in the network and which can be integrated using planar waveguide technologies. Each OCDM transceiver as well as the network is connected to the splitter via a pair of fibres for the two transmission directions. This set-up has the advantage that the same splitter can be used for both directions to and from the transceivers on one side and to and from the network on the other side.

Abstract: An optical element has a small reflection loss of light on a boundary surface between a photonic crystal and the normal medium. The optical element includes: a normal medium region having a first refractive index; a photonic crystal region having a refractive index which is changed periodically depending upon a position thereof, the photonic crystal region having as an averaged refractive index a second refractive index different from the first refractive index; and an intermediate region interposed between the normal medium region and the photonic crystal region, the intermediate region having a refractive index which is gradually changed from the first refractive index to the second refractive index.

Abstract: An optical device comprises a first birefringent crystal having a first length, a second birefringent crystal having a second length, and a dynamic polarization rotator. An optical signal propagating through the first and second birefringent crystals has an effective optical path length based, at least in part, upon the first length of the first birefringent crystal and the second length of the second birefringent crystal. The dynamic polarization rotator adjusts the effective optical path length of the optical signal in response to a control signal.

Abstract: A method and apparatus for modulating light, wherein a light source provides light of a certain wavelength to be modulated by a layer of superconducting material which forms part of a specifically configured plate assembly. The superconducting layer is placed in the optical path of the light source. Further the superconducting layer is switched between a partially transparent non-superconducting state and a substantially non-transparent superconducting state by a modulation circuit. The resulting optical pulses transmitted through the superconducting layer are converted from the original wavelength to a lower wavelength by a frequency converting device.

Abstract: An active, optical, piezoelectric actuated modulator allows switching between a reflecting state and an anti-reflecting state. The modulator, or switch, is based on the precise controlling of an air gap between a thin film membrane and a substrate. The thin film membrane is deformed by a miniaturized adaptive material, such as electrostrictive or piezoelectric (PZT) material. Maximum optical reflection is realized when the air gap is equal to a multiple of a quarter wavelength of an impinging optical beam, while anti-reflection is achieved when the thickness of the air gap is equal to zero or is different from a multiple of the quarter wavelength of the optical beam.

Abstract: The invention concerns an optical device for wavelength interleaving or dissociation (1) comprising means for coupling (4) a luminous flux generated by a source (3) in an input fiber (2), a circulator (5) linked to this input fiber (2) and to an output fiber (7) forming a first output gate of the optical device (1), a polarisation beam splitter (9) receiving the luminous flux coming out of the circulator (5) and separating it into two components (r1) and (r2). It also comprises means for transferring (14) the luminous flux from one output to the other, a birefringent medium (15) interposed on the optical path and a fiber (16) forming a second output of the optical device (1).

Abstract: A polarization-independent optical switch is disclosed for switching at least one incoming beam from at least one input source to at least one output drain.

Abstract: Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the “ladder”experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments.

Abstract: Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the “ladder” experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments.