Abstract: An electro-optic modulator and associated method are provided. The electro-optic modulator includes an optical waveguide comprised of two pairs of coplanar modulation strips, the strips being driven by a controller circuit which applies voltages of equal amplitude and opposite polarity to the strips of each pair. The voltage applied to the first pair of strips may differ from the voltage applied to the second pair of strips, so that a chirp factor may be adjusted if desired. The modulator and associated method exhibit reduced drive voltage requirements.

Abstract: An optical system may be formed by including a plurality of discrete protrusions comprising electro-optic material. Each discrete protrusion is electrically and optically isolated from each other. The protrusions further have defined a top face, a bottom face, a first side face or first and second side faces, and front and back faces. A plurality of electrodes are associated with each of the protrusions. The electrodes are capable of inducing an electric field in the electro-optic material for independently modulating one or more light beams which are incident upon one of the faces of the protrusions.

Abstract: Two-dimensional photonic crystal slab apparatus and a method for fabricating two-dimensional photonic crystal slab apparatus. A two-dimensional photonic crystal slab apparatus has a photonic crystal slab containing a two-dimensional periodic lattice, and upper and lower cladding layers for the photonic crystal slab, the upper and lower cladding layers each having a metallic cladding layer. The metallic cladding layers permit achieving substantially perfect light transmission through a waveguide in the slab, even when the waveguide is strongly bent. The fabrication method includes forming a two-dimensional photonic crystal slab from a dielectric slab supported on a substrate by, for example, an etch process.

Abstract: A photonic crystal comprises a plurality of elongated elements formed of a first dielectric material and arranged in a two-dimensional periodic honeycomb lattice. A second dielectric material surrounds the elongated elements and extending between them. The second dielectric material defines between the elongated elements a plurality of spaces filled with a third dielectric material. The first dielectric material has permittivity that is greater than permittivity of the second dielectric material and permittivity of the third dielectric material.

Abstract: A device for tuning the propagation of electromagnetic energy. The device includes a first and a second periodic dielectric structure. One of the periodic dielectric structures is movable with respect to the other periodic dielectric structure to modify a composite propagating wave characteristic of the device.

Abstract: An electrooptical deflector that overcomes conventional geometry limitations and can deflect an optical beam at high speed with high deflection angle and high resolution. It comprises an array of waveguide optical channels having an electrooptical layer sandwiched between a bottom and a top electrodes. Either the top electrode further comprises two sets of prism-shaped electrodes; or, the electrooptical layer further comprises two sets of prism-shaped spontaneous polarization domain regions. Linear phase differences are induced among a group of sub-light beams travelling in the individual optical channels. After leaving the individual optical channels, the sub-light beams are merged and the merged light beam is deflected along a direction depending on a voltage or a pair of voltages applied between the top and bottom electrodes. The optical defector requires one or a pair of low driving voltage(s) with a simple driving scheme.

Abstract: A co-planar waveguide interferometric electro-optic modulator that reduces the bias point sensitivity of the modulator to ambient temperature and to applied RF is described. The modulator includes a first and second waveguide that are formed in an electro-optic substrate. A RF electrode is positioned on the electro-optic substrate between the first and the second waveguide. A ground electrode that may include a slot is positioned proximate to the second waveguide. A guard ground electrode is positioned proximate to the first waveguide to sink heat from the RF electrode and may also balance the thermal stress in the two waveguides. A dielectric material may also be positioned proximate to the first waveguide to balance the thermal stress in the two waveguides.

Abstract: A light shutter device which has a plurality of light transmitting portions (light shutter elements) on a planar PLZT substrate. By applying voltages between a common electrode and individual electrodes to apply electric fields to the light shutter elements, the light shutter elements transmit and shut light individually. Suppose each of the individual electrodes faces the common electrode at a distance L and has a dimension W in a direction perpendicular to the direction of electric field, W/L>2. Suppose each of the individual electrodes has a dimension D in the direction of electric field, preferably D/L>0.5. Further, the individual electrodes are so placed that the distance between a side of one light shutter element which extends in a direction perpendicular to the direction of electric field and each of the individual electrodes which drive the other light shutter elements is not less than 5L.

Abstract: An optical beam steerer includes one or more layers of electro-optically active material in which is formed a chirped distributed Bragg reflector. An electric field generated across the electro-optically active material in the direction of propagation of the chirped distributed Bragg reflector causes the index of refraction within the material to change. The electric field varies in a direction normal to the direction of propagation of the chirped distributed Bragg reflector which causes a variation in the local index of refraction proportional to the strength of the electric field. Changes in the index of refraction cause the wavefront of the incident optical beam to experience different delays such that the incident optical beam is reflected out of the beam steerer at an angle that is tangential to the direction of variation of the applied electric field. Two dimensional beam steering is provided by the creation of two electric fields that are orthogonal to each other.

Abstract: A system (10) for rotating a polarization state of a beam of electromagnetic energy (22) of the present invention. The system (10) includes a first mechanism (16) for receiving the beam of electromagnetic energy (22). The beam of electromagnetic energy (22) is characterized by a first arbitrary polarization state oriented at a first angle. A second mechanism (16, 18, 20) orients the first arbitrary polarization state, via one or more waveplates (16, 18, 20), at a second angle that is different from the first angle. In a specific embodiment, the one or more waveplates (16, 18, 20) include a first quarter waveplate (16) having a principal axis (26) angled at 45° from horizontal relative to a given reference frame. A second quarter waveplate (20) is angled at −45°.

Abstract: The invention relates to a transversal electrooptical modulator (10) which can be controlled by means of an electric amplifier, comprising at least two elements for modulating (11) the light wave of a laser beam, and can preferably be used for projection of TV images. The invention is characterized in that the modulator elements are arranged behind each other in relation to the laser beam, that a focusing device (14) is arranged both in front of and behind each modulator element, that an electric amplifier output (22, 23) is associated with each modulator element and that all electric amplifier (A) inputs (24, 25) are connected to the same control line (26) as the control signal.

Abstract: The present invention provides a method for calculating the birefringence of an optical element and selecting the direction of minimum birefringence in the optical element. The birefringence of the optical element is calculated by converting known piezo-optical constants in a specified three-dimensional orthogonal coordinate system for the optical material into piezo-optical constants in an arbitrary three-dimensional orthogonal coordinate system. The amount of change in the refractive index &Dgr;n1 of the optical material in a first direction and the amount of change in the refractive index &Dgr;n2 of the optical material in a second direction which is perpendicular to the first direction are calculated using a uniaxial stress that is applied to the optical material along the first direction.

Abstract: A method of laser machining using an ultra-fast pulse laser is presented. According to the present invention a plurality of holes with a pitch less than the wavelength of the laser are drilled into a material sample. Reliable and reproducible hole drilling is accomplished through an exemplary drilling sequence which applies a number of pulses at a first pulse energy to the surface spaced to avoid laser hardening of the surface for adjacent holes of a first set of holes. Next, the number of pulses is increased or the energy of the laser beam is increased to drill holes that are interstitial to the first set of holes. The exemplary laser machining process may used to produce both one-dimensional and two-dimensional photonic crystals, among other applications.

Abstract: The invention relates to a transverse electro-optic modulator for modulating a light beam having a mean wavelength &lgr;. The transverse electro-optic modulator includes at least one birefringent single-crystal modulator element of a predefined length, and controlled by means of an electronic amplifier. The transverse electro-optic modulator further includes a compensator element is made of the same birefringent single-crystal material. The invention is characterized in that for any thickness and a defined length, the thickness of the at least one modulator element is less than both the height and the width of the compensator element.

Abstract: An optical modulator is provided to control the intensity of a transmitted or reflected light. In a transmission mode, a separator splits arbitrarily polarized light into two polarization rays and one is made to travel a separate path from the other. A recombiner causes the two rays to recombine at an output unless an electro-optic phase retarder changes the polarization of the two rays, in which case, both of them miss the output by an amount which is a function of the voltage on the retarder. A normally-off version with low polarization mode dispersion is obtained by changing the orientation of the recombiner. A normally-on version with low polarization mode dispersion is obtained with a passive polarization direction rotator. Similar results can be obtained in a reflection mode where the input and output are on the same side of the modulator. Versions using a GRIN lens are particularly suited to modulation of light out of and back into fiber-optic cables.

Abstract: A traveling wave optical modulator comprising a substrate made of a ferrodielectric electro-optic single crystal and having a pair of opposing main planes, an optical waveguide formed on a side of one of the main planes of the substrate, and a pair of electrode films which apply a voltage for modulating a light transmitting through the optical waveguide and between which the optical waveguide is located, wherein the thickness of each of the electrode films is not less than 20 &mgr;m and a width of a gap between a pair of the electrode films is not less than 25 &mgr;m.

Abstract: An improved linear light modulator array is formed with opposing electrodes which extend away from the optic surfaces of optoelcctronic material used to form the array. A uniform electric field is created across a modulator volume, generally perpendicular to light propagation within the modulator volume. The modulator volume of an element in the array is a function of electrode length, width and separation. Additional elements are defined by additional pairs of electrodes. The geometry is obtained by cutting optoelectronic material into strips. Cut sides of the strips are metallized, one at a time, with the opposite side temporarily affixed to a carrier. Aligned trenches are cut in the metallized strips to separate electrode pairs and define array elements.

Abstract: An optical scanning and imaging system and related method for scanning and imaging an object is disclosed. The scanning and imaging system does not use mechanically moving components to achieve lateral scanning of an object. Instead, the system includes a deflecting prism comprised of a material having an index of refraction that varies with changes in an applied electromagnetic field and that remains substantially constant with changes in wavelength of incident light within a predetermined wavelength range. An optical fiber transmits light within a predetermined wavelength from a light source through a gradient index lens which sends a collimated beam of light to the prism. Due to the unique properties of the prism, the light is deflected at a substantially constant angle within a lateral scanning plane. An objective lens can be used to further focus the light exiting the prism prior to directing it on the object being imaged.

Abstract: A travelling wave-type optical modulator has a supporting substrate and a ferroelectric single crystalline layer on the supporting substrate. The ferroelectric single crystalline layer has thicker parts and thinner parts within the modulating region of the travelling wave-type optical modulator as viewed in the cross section of the modulating region. Then, an optical waveguide is formed in the thicker part of the ferroelectric single crystalline layer, and electrodes for modulation are provided on the thinner part of the ferroelectric single crystalline layer in between the adjacent thicker parts.

Abstract: An optical signal processor is disclosed comprising a first optical path having a first electroabsorption optical modulator to be applied with a constant voltage and to absorb light of a signal wavelength, a second optical path having a fixed phase relation with the first optical path relative to a probe wavelength, a probe light introducer for dividing probe light of the probe wavelength into two portions and feeding them respectively into the first and second optical paths, an original signal light introducer for introducing original signal light of the signal wavelength into the first electroabsorption optical modulator, and a combiner for combining both light of the probe wavelength passed through the first and second paths.

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: In an optical voltage sensor which comprises a sensor part having a polarizer 1, a crystal &lgr;/4 plate 2, a LiNbO3 crystal 3, and an analyzer 4, a light emission part 10 emitting a light beam to the sensor part through an optical fiber, and a light reception part 12 for receiving the light beam having passed the sensor part through another optical fiber, the optical fiber used therein is a type having a core diameter allowing the beam to satisfy a range of 0.8 to 1.4° for a beam edge angle of the beam on the LiNbO3 crystal. Alternatively, another type of optical fiber may be used in the light reception part 12, having a core diameter or NA which allows the light reception part 12 to selectively receive only partial beams satisfying the range of 0.8 to 1.4° for the beam edge angle of the beam on the LiNbO3 crystal. With such structure, the optical voltage sensor can have improved temperature dependence and can be manufactured with ease and low cost.

Abstract: The achromatic variable view window or lens enables a user to change the views possible through a window from a given perspective point. One embodiment includes two variable electrooptically addressed materials, temperature regulating element, insulating layer, mounting structures, and operating software. The system relies on forming parallel and/or concentric circle arrays. Whereby the arrays are formulated such that varying the angle at which each of two materials transition between their respective &eegr;e and &eegr;o states produces a calculated and predictable deflection upon a poly chromatic incident ray while dispersion of the ray is reduced to a controllable tolerance. Objectives of this new art are to maximize refraction, control dispersion, and eliminate physical motion. It can operate as a variable angle achromatic prism when addressed in parallel arrays or a variable focal length achromatic lens when addressed in concentric circular arrays.

Abstract: A glass substrate for a display with a thickness of from 0.3 to 6 mm, which has an average WCA (filtered center line waviness: JIS B0651) of from 0.03 to 0.5 &mgr;m measured with a contact-type surface roughness measuring instrument using a phase compensation 2RC zone filter with a cutoff value of 0.8 to 25 mm over a measuring length of 200 mm.

Abstract: An optical modulation element is capable of forming a reflective diffraction grating in which heights of a plurality of elements each having a reflecting surface periodically change. The reflecting surfaces of at least one of the plurality of elements are driven in a direction of height by piezoelectric elements. The plurality of elements each having the surface as the reflecting surface are two-dimensionally arrayed by juxtaposing long sides. A rear surface side of an effective reflecting portion of each of the elements is fixed to the piezoelectric element.

Abstract: An optical modulator is provided to control the intensity of a transmitted or reflected light. In a transmission mode, a separator splits arbitrarily polarized light into two polarization rays and one is made to travel a separate path from the other. A recombiner causes the two rays to recombine at an output unless an electro-optic phase retarder changes the polarization of the two rays, in which case, both of them miss the output by an amount which is a function of the voltage on the retarder. A normally-off version with low polarization mode dispersion is obtained by changing the orientation of the recombiner. A normally-on version with low polarization mode dispersion is obtained with a passive polarization direction rotator. Similar results can be obtained in a reflection mode where the input and output are on the same side of the modulator. Versions using a GRIN lens are particularly suited to modulation of light out of and back into fiber-optic cables.

Abstract: Disclosed herein is a self-waveguide optical circuit for forming optical paths by propagating rays or electromagnetic waves comprising: photonic crystals having a dielectric constant periodic structure or a dielectric constant semi-periodic structure having a period substantially corresponding to a wavelength of propagation rays, and optical paths formed by establishing a crystal direction of the photonic crystal to level the dispersion surface of the photonic crystal for obtaining a bundle of parallel rays. In accordance with the present invention, elevation of characteristics such as miniaturization, high integration, high speed operation and transmission efficiency can be obtained because a bundle of parallel rays can be obtained without forming crooked parts having an excessive curvature radius.

Abstract: A small sized electro-optic voltage sensor capable of accurate measurement of high levels of voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation into the sensor. A polarization beam displacer serves as a filter to separate the input beam into two beams with orthogonal linear polarizations. The beam displacer is oriented in such a way as to rotate the linearly polarized beams such that they enter a Pockels crystal at a preferred angle of 45 degrees. The beam displacer is therefore capable of causing a linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels electro-optic effect induces a differential phase shift on the major and minor axes of the input beam as it travels through the Pockels crystal, which causes the input beam to be elliptically polarized.

Abstract: A light modulating or switching array (10) having a plurality of discrete protrusions (16) formed of electro-optic material, each of which is electrically and optically isolated from each other. The protrusions (16) have defined a top face (20), a bottom face (30), first and second side faces (22, 24), and front and back faces (26,28). There are a plurality of electrodes (34) associated with each of the protrusions (16), these electrodes (34) being capable of inducing an electric field in the electro-optic material for independently modulating a plurality of light beams which are incident upon one of the faces (20, 22, 24, 26, 28, 30) of the protrusions (16). The electro-optic material may be of PLZT, or a member of any of the groups of electro-optic crystals, polycrystalline electro-optic ceramics, electro-optic semiconductors, electro-optic glasses and electro-optically active polymers.

Abstract: The present invention provides a method for calculating the birefringence of an optical element and selecting the direction of minimum birefringence in the optical element. A material for manufacturing the optical element is a fluoride single crystal with a birefringence value that is reduced compared to conventional materials. The fluoride single crystal is cut from a fluoride single crystal ingot obtained by crystal growth so that the {111} crystal planes are two parallel planes, after which the optical performance is improved by subjecting this material to a heat treatment. The birefringence of the optical element is calculated by converting known piezo-optical constants in a specified three-dimensional orthogonal coordinate system for the optical material into piezo-optical constants in an arbitrary three-dimensional orthogonal coordinate system.

Abstract: A light modulating or switching array (10) having a plurality of discrete protrusions (16) formed of electro-optic material, each of which is electrically and optically isolated from each other. The protrusions (16) have defined a top face (20), a bottom face (30), first and second side faces (22, 24), and front and back faces (26,28). There are a plurality of electrodes (34) associated with each of the protrusions (16), these electrodes (34) being capable of inducing an electric field in the electro-optic material for independently modulating a plurality of light beams which are incident upon one of the faces (20, 22, 24, 26, 28, 30) of the protrusions (16). The electro-optic material may be of PLZT, or a member of any of the groups of electro-optic crystals, polycrystalline electro-optic ceramics, electro-optic semiconductors, electro-optic glasses and electro-optically active polymers.

Abstract: A tunable photonic band-gap device is disclosed which utilizes photoresponsive materials and is tunable over a range of wavelengths with the application of light. The device comprises a structure having a plurality of photoresponsive regions arranged in a matrix whereby the behavior of the device in preventing electromagnetic radiation from propagating through the structure may be modified by applying light to the photoresponsive regions. In one embodiment, a photonic band-gap transistor has a light propagation path defined by a plurality of dielectric and photoresponsive rods disposed in a substrate for the routing of a signal through the structure from an inlet to an outlet. The path comprises an input signal path beginning at the inlet, an output signal path terminating at the outlet, and a control signal path which merges with the input signal path to be joined with the output signal path at a common intersection point.

Abstract: A light modulation apparatus includes: a light modulation device including first light transmission control elements each for controlling the amount of transmission of a light beam, for generating and applying a modulation light beam representing a modulation signal by controlling the amount of transmission of the light beam in each of the first light transmission control elements in accordance with the modulation signal; and a detection light beam generating device that always allows transmission of a part of the light beam for generating and applying a detection light beam for detecting a displacement of the irradiation position of the modulation light beam.

Abstract: A two-dimensional light valve array comprising a pattern of reduced electrode spacing solid state light valves formed using semiconductor processing techniques, and a method of making same. The electrodes are recessed into channels in an electro-optic substrate, such as lanthanum modified lead zirconate-titanate (PLZT). A first set of electrodes are deposited in a comb-shaped configuration into parallel and orthogonal channels etched into the PLZT substrate. A second set of deposited electrodes are bands running in alternating channels between the teeth of the first set of electrodes. An insulating material isolates the two sets of electrodes. An applied voltage between the electrodes induces bi-refringence in the PLZT and affects light transmissivity through the light valve at that location. The array is activated electronically by means of matrix addressing and controlled by means of a microcomputer and appropriate software.

Abstract: SrxBa1−xNb2O6, where x is greater than 0.25 and less than 0.75, and KNbO3 ferroelectric thin films metalorganic chemical vapor deposited on amorphous or cyrstalline substrate surfaces to provide a crystal axis of the film exhibiting a high dielectric susceptibility, electro-optic coefficient, and/or nonlinear optic coefficient oriented preferentially in a direction relative to a crystalline or amorphous substrate surface. Such films can be used in electronic, electro-optic, and frequency doubling components.

Abstract: The present invention provides a method for calculating the birefringence of an optical element and selecting the direction of minimum birefringence in the optical element. A material for manufacturing the optical element is a fluoride single crystal with a birefringence value that is reduced compared to conventional materials. The fluoride single crystal is cut from a fluoride single crystal ingot obtained by crystal growth so that the {111} crystal planes are two parallel planes, after which the optical performance is improved by subjecting this material to a heat treatment. The birefringence of the optical element is calculated by converting known piezo-optical constants in a specified three-dimensional orthogonal coordinate system for the optical material into piezo-optical constants in an arbitrary three-dimensional orthogonal coordinate system.

Abstract: Optical devices using non-centric crystals, such as lithium niobate, and methods for making and using the devices, are provided. The devices provide improved temperature stability as compared to conventional devices using non-centric crystals. The improved temperature stability is provided by etching the surface of a non-centric crystal to a depth of less than about 300 angstroms. The devices and methods of the invention reduce the magnitude of change in bias voltage required to maintain an optical crystal at a pre-selected operating point.

Abstract: Polyhalide light-polarizing particles prepared by the process comprising reacting in a suitable liquid (i) elemental molecular iodine, (ii) an inorganic halide, with (iii) a substantially rigid polycyclic precursor compound, wherein:a. the polycyclic precursor compound has two cyclic structures linked together via an aromatic or heteroaromatic group;b. the three-dimensional structure of the polycyclic precursor compound has a cavity defined by the two cyclic structures and only one opening into the cavity; andc. polar groups are provided in the outside of the polycyclic precursor compound; andd. one of more chelating group or groups are provided inside the cavity of the precursor group for chelating hydrogen or metal ions.

Abstract: In an organic/inorganic composite superlattice type optical modulator capable of entering/projecting light, and capable of modulating an optical characteristic such as transmittance, reflectivity, and a refractive index of light in response to an externally controlled electric field, or light, the organic/inorganic composite superlattice type optical modulator includes at least one type of a compound semiconductor layer and at least one type of an organic compound layer; the compound semiconductor layer and the organic compound layer are alternately stacked in greater than one period; at least one of the compound semiconductor layer and the organic compound layer being crystalline; and also a thickness of each of the layers is made larger than a Bohr radius of the compound semiconductor and smaller than 10 times the Bohr radius. As a result, this novel optical modulator can provide a high nonlinear characteristic by a semiconductor modulator, and a high response characteristic by an organic modulator.

Abstract: An optical modulator controllably attenuates an optical signal by changing the index of refraction of an electro-optic prism in the modulator by varying the electrical bias applied to the electro-optic prism. Changing the index of refraction alters the path along which the optical signal travels through the optical modulator. By appropriately focusing the optical signal, the location of the optical signal relative to an output fiber can be controlled to vary the degree of optical coupling between the optical signal and the output fiber, thereby changing the amplitude of the outgoing optical signal. In one embodiment, the optical modulator has an electro-optic prism located between a lens and a mirror, where the mirror reflects the optical signal to pass through the prism and the lens two times: once along an input path and once along an output path.

Abstract: Optical modulators and switches for use in telecommunications systems are disclosed having solid-state crystalline optical material comprised of III-V, II-VI, and IV semiconductor nanocrystals embedded in a polymer matrix. In a preferred embodiment, the crystalline material comprises CdSe crystals sized at less than 5.8 nm in diameter and more preferably at less than about 4 nm in diameter and advantageously embedded in poly(vinyl pyridine). The crystalline material sandwiched between two electrodes defines an optical modulator. In one preferred embodiment, the crystalline material with ten-percent crystal embedded in a polymer will exhibit with an applied voltage of 100V, a differential absorbance spectra (.DELTA.A) of about 50 cm.sup.-1 at wavelengths of about 610 nm and a differential refractive index (.DELTA.n) of about 10.sup.-4 at wavelengths of about 625 nm.

Abstract: A method for mechanically stabilizing and for tuning a filter having a photonic crystal structureThe cavities of the filter fabricated as a photonic crystal structure are filled with optically transparent material having an adjustable refractive index. The optical properties of the filter and, thus, the filtering action are adjusted by way of an electric field having a variable field strength.It is possible to produce small-dimensioned, narrow-band filter elements, which are finely tunable and tunable within a broad range, and to realize them as filter elements which are integrated with a high packaging density.

Abstract: The invention concerns a planar electro-optical light-beam deflector with a line of prismatic deflectors, arranged side by side, exhibiting electrodes to which an electric voltage can be applied. It is essential to the invention that the light beam is conveyed in a Z-cut lithium niobate or lithium tantalate crystal, preferably in a monomodal layer waveguide extending along the surface of the latter, the prismatic deflectors each consisting of two triangular or prismatic zones in which a largely uniform polarization direction is generated by inversion of the polarization direction determined by the E-field vector in domains with spontaneous polarization in the opposite direction, each triangular zone exhibiting polarization in the direction opposite to that of the one adjacent to it, and that a rectangular electrode covering the triangular zones is attached to the upper side of the crystal and a counterelectrode to the lower side of the same.

Abstract: A reversible and conservative photon routing switch is implemented as a room temperature, optical, vertical cavity X-gate (also sometimes known as a Fredkin gate). Such gates are primitive structures into which all logic functions can be decomposed. The construction of the device makes it uniquely suited to dense packed arrays of optoelectronic components for optical routing and logic. In one of the switching states, light incident on the device from either side of the wafer will pass through the device (the device is bi-directionally transmissive). In the other switching state, light incident from either side of the wafer will be reflected. Switching can be performed using either electrical or optical control. Thus incident photons are either routed through the device or reflected from the device.

Abstract: The copolymer described is a segmented copolymer consisting essentially of organic segments A which have a number i of reactive ends such that i is from 1 to 6 inclusive, and segments B which have a number j of reactive ends such that j is from 1 to 6 inclusive. The segments B have redox properties and each segment A is connected to at least one segment B by a group Y and vice versa, the group Y being an ether, thioether, secondary amine, tertiary amine, secondary amide, tertiary amide, imide, quarternary ammonium group, or a group having a carbon--carbon bond. The respective weighted molar mean of i and j is 2 or more. Application to electrochemical generators and electrochromic systems.

Abstract: A method for forming relatively large and inexpensive crystals of KTiOPO.sub.4, which exhibit relatively low conductivities, is disclosed. In addition, electro-optic devices based on such crystals are also disclosed.

Abstract: An electro-optic modulator array (36). Electrode pairs 50 and 51 are mounted on a substrate (40). A layer of electronic grade glass (60) is deposited by electron beam evaporation on the substrate (40) and electrodes (50) and (51). In an alternate embodiment, an electronic grade of glass 50 is deposited on the PLZT substrate (40) prior to applying electrodes (50) and (51).

Abstract: The method for switching optical radiations having orthogonal polarization includes the steps of inserting a linearly polarized wave into the input of a birefringent object (an optical waveguide or crystal) and feeding a small polarized small optical signal is also orthogonally into the object. The polarization vector of the linearly polarized pumping signal or of the optical signal is directed along an optical axis of the birefringent object or at a small angle to the optical axis. The pumping intensity is selected to be higher than the threshold value I.sub.p, which is proportional to a difference between the effective refractive indices of orthogonally polarized radiations and inversely proportional to a cubic nonlinear coefficient of the object. In addition, the intensity of the optical signal radiation is varied from zero to a maximum value of <0.1 I.sub.p.

Abstract: A spatial light modulator including a thin layer of solid-state electro-optical material having parallel, opposite first and second surfaces, an elongated first electrode disposed on the first surface and a plurality of spaced, elongated second electrodes disposed on the second surface and generally perpendicular to the first electrode. The layer of solid-state electro-optical material has a thickness in the range of approximately 5 to 15 microns, and is composed of PLZT. In one embodiment, a plurality of thin regions of insulator are disposed on the first surface between portions of the first electrode and the electro-optical material.

Abstract: An optical single crystalline article comprising a substrate made of an optical single crystal and an epitaxial film formed on said substrate and made of an optical material, wherein a crystalline structure of said epitaxial film is a relaxed structure.