Abstract: A method of displaying an image with a display device including a plurality of display pixels includes receiving image data for the image, the image data including individual pixels of the image; buffering the image data and creating a frame of the image, the frame of the image including a plurality of columns and a plurality of rows of the pixels of the image; defining a first sub-frame and at least a second sub-frame for the frame of the image, image data of the second sub-frame being offset from image data of the first sub-frame by an offset distance of at least one pixel; and displaying the first sub-frame with a first plurality of the display pixels and displaying the second sub-frame with a second plurality of the display pixels offset from the first plurality of the display pixels by the offset distance.

Abstract: An element for steering electromagnetic beams. The element includes a phase change material in combination with dielectric and other layers in a multilayer optical stack. The phase change material that is reversibly transformable between two or more structural states, where different structural states differ with respect to refractive index and/or extinction coefficient. The structural state of the phase change material establishes a phase angle state for the element that dictates the direction of propagation of an output beam produced from an incident electromagnetic beam. Depending on the structural state, the element adopts one of two principal phase angle states and a binary beam steering capability is achieved in which an incident electromagnetic beam can be redirected in either of two directions. In a preferred embodiment, the output beam is a reflected beam and the element includes a phase change material sandwiched between two dielectric materials and supported by a metal layer.

Abstract: A grating coupled surface plasmon resonance optical modulator is disclosed. A electro-optic polymer dielectric is deposited on the metallic surface of a diffraction grating to provide a metal/dielectric interface. A surface plasmon will propagate at the metal/dielectric interface in a resonant condition, e.g., when the metal surface is illuminated by transverse magnetic (TM) polarized light of the appropriate wavelength, angle of incidence and phase velocity. In the present invention, phase velocity is controlled by the diffraction grating. A transparent electrode deposited on the electro-optic layer allows an electrical potential to be applied across the electro-optic polymer. The applied electrical potential (voltage) changes the index of refraction of the electro-optic polymer, thereby disrupting the resonant condition to produce an optically detectable change in reflectance of incident light from the metal layer.

Abstract: A system and method for recovery of phase information from recorded intensity values is disclosed. In one aspect, a phase filter is placed in a plane, which may be the back focal plane (BFP) of a lens used for observing an object. The phase filter changes the phase of a wave front distribution in the BFP in a known manner. Amplitude stops or combinations of phase and amplitude filtering patterns can also be used to capture N different sets of intensity data in a conjugate diffraction plane. The N intensity images are used to obtain an estimate of the wave front at the first plane. This wave front estimate is then used to generate N modified estimates of the wave front at the conjugate plane, each modified estimate corresponding to one of N filtering patterns. In one implementation, the N modified IP estimates are corrected by replacing the estimated amplitudes with the actually measured ones for that image.

Abstract: A piezoelectric device is disclosed, which includes a first element of porous crystalline material, a second element being attached to, or integrally formed with, the first element, and at least one electrode being in electrical contact with the first element, such that subjecting the first element to an electric potential via the at least one electrode results in a strain induced by the first element on the second element. Also disclosed is a piezooptic device which includes a first element of porous crystalline material, a second element being attached to, or integrally formed with, the first element, and a light source, such that subjecting the first element to light originating from the light source results in a strain induced by the first element on the second element.

Abstract: An element for reflecting, transmitting, focusing, defocusing or wavefront correction of electromagnetic radiation in the terahertz frequency range. The elements include a grid of conductive strips including active regions comprising a chalcogenide phase change material. The chalcogenide material can be in an amorphous, crystalline or partially crystalline state. The dispersive characteristics of the grid (e.g. impedance, admittance, capacitance, inductance) influence one or more of the reflection, transmission, state of focusing or wavefront characteristics of incident electromagnetic radiation through the action of a stored phase taper formed by establishing a crystallinity gradient over a series of active chalcogenide regions or domains in one or more directions of the element.

Abstract: In one embodiment, a laser refraction system includes a refracting unit to refract light emitted from a laser. A refracting unit control procedure configures a charge on an OPC according to an image by sending a signal to the refracting unit to control refraction degree and timing.

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: Provided is an optical switching system which is capable of being operated at a very high speed in a communication wavelength region and of meeting the various requests at a high grade by the provision of an optical switching system having such a construction that a signal light composed of a light pulse train, and a pulse-like control light synchronous therewith are applied to a light control portion composed of a thin film made of carbon nanotubes to selectively transmit the light pulse train in the signal light through the thin film to form an output signal light and then receiving the output signal light thus formed is received.

Abstract: The present invention pertains to an optical shutter comprising an photon-absorbing layer and a surface layer in a transparent state on at least one side of the photon-absorbing layer, wherein the optical shutter is characterized by the absorption of photons to change the photon-absorbing layer to an opaque state and to change the surface layer to a reflective state. The optical shutter is reversibly imageable between these transparent and reflective states. The optical shutter may comprise a metallized layer on at least one side of the photon-absorbing layer. Preferably, the optical shutter comprises an organic free radical compound, such as a salt of an aminium radical cation, in the photon-absorbing layer. Also provided are optical switch devices and optical buffers comprising such optical shutters and methods of switching an optical signal utilizing such optical shutters and switch devices.

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: A piezoelectric device is disclosed, which includes a first element of porous crystalline material, a second element being attached to, or integrally formed with, the first element, and at least one electrode being in electrical contact with the first element, such that subjecting the first element to an electric potential via the at least one electrode results in a strain induced by the first element on the second element. Also disclosed is a piezooptic device which includes a first element of porous crystalline material, a second element being attached to, or integrally formed with, the first element, and a light source, such that subjecting the first element to light originating from the light source results in a strain induced by the first element on the second element.

Abstract: An optical gate according to the invention comprises a polarization divider to divide an optical signal into two orthogonal polarization components and to output them as a first polarization component which precedes in the time base and a second polarization component which follows the first one in the time base; a semiconductor optical amplifier to modulate the phase of the second polarization component output from the polarization divider according to a control light; an assist light supplier to supply to the semiconductor optical amplifier an assist light to help the recovery of the refractive index variation of the semiconductor optical amplifier caused by the control light; a polarization combiner to combine the first and second polarization components of the optical signal transmitting on the semiconductor optical amplifier so as to adjust them in the same time location; and a polarization extractor to extract a predetermined polarization direction component from the output from the polarization combine

Abstract: An optically addressed spatial light modulator may be formed with an integrated light emitting device display. The light emitting device display may be formed of a size and cost that optimizes the overall modulator design. In addition, by integrating the modulator and display devices, the overall size of the spatial light modulator may be reduced in some embodiments.

Abstract: An array of devices for electronically steering a laser beam. A plurality of quantum well absorption modulators steer a laser beam, either reflective or transmissive, without moving parts and operable at room temperature. The foregoing is accomplished using intraband, also termed intersubband, transitions in the quantum wells.

Abstract: A laser processing device comprising: an optical system having a laser beam source, and an air-tight chamber provided separately from the optical system, wherein the chamber has a transparent portion for transmitting a laser beam emitted from the laser beam source, on a light-receptive face thereof receiving the laser beam, the chamber is capable of accommodating a donor substrate on which an organic substance layer including at least a luminous layer to be transferred is formed and an acceptor substrate onto which the organic substance layer is transferred from the donor substrate by the laser beam transmitted through the transparent portion, and the inside of the air-tight chamber is in an inert gas atmosphere or in a vacuum atmosphere.

Abstract: A surface plasmon optical modulator element includes a dielectric material block disposed so that light-to-be-modulated travels through the interior of the dielectric material block and impinges upon one surface thereof at an angle of total reflection, a metal film formed on the surface of the dielectric material block, a photo-functional film which is formed on the metal film and whose refractive index is changed upon exposure to light, and a modulating light source which projects modulating light onto the photo-functional film. The photo-functional film is formed of dye which contains an electron donor and an electron acceptor so that a photoelectron can be transferred therebetween.

Abstract: An optical communication device includes a first photon source emitting a first beam modulated with information. The first beam intersects a thin metal film and engenders a first surface plasmon wave thereon. Part of the first beam reflects from the metal film to form a reflected beam. A polarization structure rotates the polarization of the reflected beam. A reflecting structure reflects the reflected beam to form a second beam propagating back toward the film, which beam passes through the polarization structure again. On the metal film, the second beam engenders a second surface plasmon wave. Interaction between the first and second surface plasmon waves creates a surface plasmon standing wave. A second source provides a third beam intersecting the first and second beams at the metal film. Interaction between the third beam and the surface plasmon standing wave modulates the third beam as it passes through the metal film.

Abstract: An apparatus comprising a tunable liquid microlens that includes a transparent supporting layer and a transparent photoresponsive layer disposed on a first surface of the supporting layer. A droplet of a transparent liquid is disposed on the photoresponsive layer. The photoresponsive layer separates the supporting layer and the droplet. At least a portion of the photoresponsive layer that contacts the droplet may be selectively irradiated by at least one light source such that a contact angle between the droplet and the photoresponsive layer may be varied and the droplet may be repositioned along the photoresponsive layer. In this manner, at least one of a focal length and a lateral position of a focal spot of the microlens may be adjusted directly by irradiation with a light beam.

Abstract: A system and method for recovery of phase information from recorded intensity values is disclosed. In one aspect, a phase filter is placed in a plane, which may be the back focal plane (BFP) of a lens used for observing an object. The phase filter changes the phase of a wave front distribution in the BFP in a known manner. Amplitude stops or combinations of phase and amplitude filtering patterns can also be used to capture N different sets of intensity data in a conjugate diffraction plane. The N intensity images are used to obtain an estimate of the wave front at the first plane. This wave front estimate is then used to generate N modified estimates of the wave front at the conjugate plane, each modified estimate corresponding to one of N filtering patterns. In one implementation, the N modified IP estimates are corrected by replacing the estimated amplitudes with the actually measured ones for that image.

Abstract: This invention pertains to a basic multi-technology application of cascaded beam-formers. A dual MEMS-EO technology platform method involving a two axis deflection micro-mirror cascaded with a three dimensional electro-optical beam-former such as a multi pixel liquid crystal device forms a powerful reflective control site for an incident beam, thereby inherently providing a robust beam control with both coarse and fine beam control capabilities in three dimensions. The electrically controlled two axis micro-mirror is excellent in providing the large angular beam deflections, while the liquid crystal device provides excellent small-beam deflections. This leads to a mechanically robust beam control module. A multipixel MEMS mirror device option coupled with the EO device can also provide simultaneous multi-beam generation capability. Furthermore, use of macro-pixels for both the MEMS and EO devices provides resistance to single pixel dependent catastrophic failure for the overall module.

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 acousto-optic device comprises a first light source for producing a light beam, a light-transmitting material capable of transmitting the light beam along an optical path through the light-transmitting material, a light-absorbing material adjacent to the light-transmitting material, and a pulsed light source capable of directing a pulsed light beam at the light absorbing material so as to produce acoustic waves within the light-transmitting material that cross the optical path of the light beam from the first light source.

Abstract: In an optical switch system for switching over plural input lights and plural output lights corresponding thereto through spatial optical connection therebetween, having: a first reflection mirror to be directed with an input light and being controllable in position thereof; a second reflection mirror disposed opposite to the first reflection mirror, for reflecting the light reflected on the first reflection mirror, so as to outputted it therefrom; means for controlling positions of the first and second reflection mirrors, respectively; and means for adjusting the position of the first and second mirrors, which are controller by the controlling means, wherein a reference light being substantially different from the input light in wavelength is generated; both the reference light and the input light reflect upon the first and second reflection mirrors; and (c) optical intensity of the reference light selectively diverged from the reflection light is detected, thereby controlling positions of the first and said

Abstract: Distortion optics are used to efficiently couple a spiral color wheel and an orthogonal modulator. Light 602 from a light source enters an aperture in a reflective end of a recycling integrator rod 604. The light travels through the rod and exits the end of the rod adjacent a sequential color filter 606, shown as a spiral color wheel. The shape of the light beam 608 exiting the integrator rod 604 is determined by the shape of the exit aperture of the integrating rod 606. The exit aperture of the integrating rod 606 typically is formed by a reflective exit aperture on the exit face. A cross section of the light beam 608 exiting the sequential color filter includes several bands of filtered light, one for each of the filter segments of the color wheel illuminated by the light beam. The curvature of the color bands makes it difficult for a row addressed spatial light modulator to efficiently use the light.

Abstract: An optical element, optical control device and optical control method are provided which demonstrate a large, rapid optical response using a laser light of low output as a control light. A signal light 1 is emitted from an optical source 1. A signal light 2 emitted from an optical source 2. A control light and the signal light are converged by a condenser lens 7, and irradiate an optical element 8. Only the signal light is detected by a photodetector 22 through a light receiving lens 9 and a wavelength selection filter 20. A thermal lens is formed reversibly in the optical element and switching the control light ON and OFF modulates the intensity of the signal light.

Abstract: Several optical heads are mounted on a common carriage adapted to scan a photosensitive printing plate. Each head is equipped with a laser source, a modulator and projection optics and can project a segment containing a plurality of pixels. The optical track of beams in each head is folded several times in such a way as to reduce the width of the head as well as its height. When the carriage moves from one edge of the plate to the other edge a swath of pixels is projected. Each head includes means to adjust the width, location, orientation and intensity of the segment it generates. Each head is accurately positioned on the carriage so that at least two abutting swaths are projected during each sweep of the carriage to produce a wider swath.

Abstract: The invention relates in particular, to the area of devices or systems whose optical operation is modified by changing the optical properties of the medium of which they are formed and that are intended, in particular, for limiting the luminous intensity transmitted by the system. Specifically, the invention relates to a device for selectively limiting the intensity of a radiation, including a liquid or solid medium containing nanotubes, for example, nanotubes made of carbon or boron, tungsten, silicon, or composite nanostructures, such as BN, BC3, BC2N, CN(C3N4), or MoS2.

Abstract: A system and method for recovery of phase information from recorded intensity values is disclosed. A phase filter, such as one or more dioptric lenses, is placed in the back focal plane (BFP) of a lens used for observing an object. The phase filter changes the phase of a wave front distribution in the BFP in a known manner. The system captures N different sets of intensity data in the image plane (IP) using N different phase filters or N phase distributions generated by an electronically variable phase filter. The N intensity images are used to obtain an estimate of the wave front at the BFP of the lens. This BFP wave front estimate is then used to generate N modified estimates of the wave front at the IP, each modified estimate corresponding to one of the N phase distributions of the BFP phase filter(s). In one implementation, the N modified IP estimates are corrected by replacing the estimated amplitudes with the actually measured ones for that image.

Abstract: An optoelectronic apparatus for detecting objects in a monitored region includes a transmitter that emits transmission light, a receiver that receives a reflected light, and an evaluation unit, in which the transit time to of the transmission light that is guided in the monitored region and reflected back, as a reflected light, by an object is evaluated. The transmitter emits the transmission light in the form of a sequence of transmission light pulses. A portion of the light quantity of a transmission light pulse is coupled out as a reference transmission light pulse and guided by way of a reference path to the receiver. The transit time tR of the reference transmission light pulse guided as a reference reflected light pulse to the receiver is determined in the evaluation unit. The transit-time difference to−tR is used to determine the distance of an object.

Abstract: The present invention discloses a method of optical correction for improving the pattern shrinkage caused by scattering of the light during photolithography processes, wherein the patterns on photomasks are corrected by providing aid patterns. Therefore, serifs or hammerheads are not necessary, and the costs can be decreased. According to the present invention, a chrome aid block is provided between the edges of the patterns. It is noted that the size of the chrome aid block is between ⅓ to ½ the wavelength of light used during exposure. Therefore, the pattern shrinkage caused by scattering of the light during exposure can be reduced, and there is no additional block formed on the photoresist layer. In addition, the standing wave effect can be prevented; thus, the pattern transfer is more accurate.

Abstract: An input optical data pulse 120 encoded by pulse amplitude modulation is branched into two parts by an optical coupler 111, and one part is input to an optical clock generation device, such as mode-locked laser diode (MLLD) 113 and the other part is input to an optical/optical intensity modulator, such as semiconductor optical amplifier 110 or electro-absorption light intensity modulator 210. A regenerated optical clock pulse drives the optical/optical intensity modulator and input optical data pulses 120 are intensity-modulated to serve as optical data pulses 121 which are output. An input optical data pulse can drive the light intensity modulator.

Abstract: A technique for marking pixels on workpieces by routing a scanned beam to different marking stations to mark individual pixels on the workpieces. A diffractive scan lens focuses the beam. A mark is formed on a workpiece by producing the mark and curing the mark. Angular position of a scanning mirror in a raster scanner is determined by moving a beam, reflected from the scanner, across rulings on an optical element during scanning. A print head for printing spots on a surface of a workpiece has a walled, internally pressurized chamber and structure for causing an inked web to conform to a contour of the chamber wall and to be pulled along the chamber wall. A print head has a compliant-walled, internally pressurized chamber. A print head has a chamber having a low-coefficient of friction coating. Two workpieces may be marked at two marking stations by two-directional scanning.

Abstract: A lens system for protecting high gain optical systems (eyes or equipment) from high intensity laser radiation includes a second mirror disposed on an exit lens, a first mirror formed by half silvering the inner surface of a focusing entry lens, and a medium such as sugar water containing aerosol particles of three-micron carbon, which induces ionization that will absorb the incoming laser radiation. One binocular embodiment uses the foregoing medium; a second binocular embodiment uses a solid lens material laden with aerosol particles.

Abstract: A combination of an optically transmissive dielectric fluid having a first refractive index and an optically anisotropic particle rotatably disposed in the fluid is provided. The particle has at least one optically transmissive region having a second refractive index. The particle provides a first optical modulation characteristic when disposed in the fluid in a first orientation with respect to a flux of optical energy, and further provides a second optical modulation characteristic when disposed in the fluid in a second orientation with respect to a flux of optical energy. The particle has an anisotropy for providing an electrical dipole moment, the electrical dipole moment rendering the particle electrically responsive such that when the particle is rotatably disposed in an electric field while the electrical dipole moment of the particle is provided, the particle tends to rotate to an orientation in which the electrical dipole moment aligns with the field.

Abstract: This monostatic LIDAR system is a pulsed-radiation LIDAR system comprising, for the separation of the laser emitter beam from the laser echo backscattered by the photodetector of the receiver, an optical separator that deflects an incident light beam in different directions, depending on whether it transmits or reflects this beam, the coefficient of transmission or the coefficient of reflection of this optical separator varying as a function of the energy density of said incident light beam. Advantageously, this optical separator is constituted by a layer of vanadium dioxide VO.sub.2 deposited on a transparent plate. An optical separator of this kind is used to obtain a total transmission/reception output greater than that of an optical separator with semi-reflective plate while, at the same time, preserving the advantages that an optical separator of this kind brings about in the optical architecture of a LIDAR, these advantages being simplicity, easy setting, compactness and low-level parasitic reflections.

Abstract: An object surface height measuring device with two acousto-optical modules for refracting light from a light emitter with predetermined refractive indices depending on frequency modulation so that the light is swept over the X and Y axes of an object, and two other acousto-optical modules synchronized with the signals of the first two acousto-optical modules, respectively, so that the light reflected from the object is focused onto a light receiving portion. The change in the height of the object is measured from the variation between the spot of light focused onto the light receiving portion and the center of the light receiver.

Abstract: The present invention relates to a new polyesterimide of the type containing ester repeat functional groups E=--CO--O--, imide repeat functional groups I: ##STR1## and at least one chromophore, characterized in that it contains a quantity of recurrent amide functional groups capable of ring closure to imides which is smaller than or equal to 5 mol % relative to the sum of the imide functional groups and of the amide functional groups capable of ring closure to imides, which are present, and in that the polymerization functional groups consist essentially of E functional groups.This polyesterimide is preferably free from amide functional groups capable of ring closure to imides.One of the processes for obtaining this polyesterimide constitutes another subject-matter of the invention.Such a polymer is advantageously capable of behaving like a material that is transparent and/or active in nonlinear optics.

Abstract: There is disclosed a reshaping device for optical short pulses to effectively perform reshaping of and eliminate noise from an optical short pulse of a pulse width of pico second order less than a carrier life time. Input optical short pulses are applied to a saturable absorption element, while an assist light of a wavelength longer than that of the input optical signal pulses is also applied to the saturable absorption element to accelerate, by stimulated emission, recombination of excited electrons and holes produced in the saturable absorption element in response to the input optical signal pulses, so that the input optical signal pulses reshaped are derived from the saturable absorption element.

Abstract: Bidirectional optical communication system transmits optical signals with two different wavelengths .lambda..sub.1 and .lambda..sub.2 (.lambda..sub.1 <.lambda..sub.2) between a broadcasting station and a plurality of ONU terminals. Bisecting separation of .lambda..sub.1 and .lambda..sub.2 requires expensive WDMs. .lambda..sub.1 -selective photodiode which absorbs all the .lambda..sub.1 light and allows all the .lambda..sub.2 to pass through is proposed. The energy gap Eg.sub.1 of the light receiving layer is determined to be smaller than hc/.lambda..sub.2 and larger than hc/.lambda..sub.1. The .lambda..sub.1 -selective photodiode and the other photodiode are positioned in series on a beam line, which dispenses with WDMs.

Abstract: Incident radiation is focussed by a lens into a non-linear optical material whose index of refraction increases with increased radiation intensity. For normal radiation, the radiation freely passes through the nonlinear optical and an optically-switchable material to an other lens. This other lens directs the radiation onto a photodetector. High-intensity radiation, however, is self-trapped in the nonlinear material to form a columnar beam which falls on the optically-switchable material, causes this material to switch, and is reflected thereby.

Abstract: An optical amplification system directs a diffraction-limited signal beam through a series of crossings, at substantially less than 90.degree. crossing angles, with a number of non-diffraction-limited pump beams in a photorefractive medium. The pump beams are e-polarized while the signal beam travels down the crystal medium's c-axis and is polarized in the same plane as the pump beam polarization, resulting in an energy transfer from the pumps to the signal beam while leaving the signal beam diffraction-limited. The photorefractive medium is preferably a series of BaTiO.sub.3 :Rh crystals that are aligned parallel to the angled edge of a wedged-shape prism through which the pump beams are transmitted, with the crystals cut so that their C-axes are parallel to the signal beam.

Abstract: An optical-scanning system including a laser, a multi-faceted, rotational scanning mirror, and system-monitoring laser safety structure operatively and informationally connected respectively to the laser and to the mirror and the drive motor for the mirror for altering the effective power output of the laser in response to current operational status of the system as determined by current operational status of the rotating mirror. The safety structure enforces on the laser a duty cycle of operation which is less than 100-percent, causes the laser to power down to a low "sleep" operating level at times other than during a normal scanning sweep, de-powers the laser entirely if either the drive motor for the mirror is not enabled or the rotational speed of the mirror is below full normal operating speed, and also positively de-powers the laser when a user shuts down the system.

Abstract: Generally and in one form of the invention this is a periodic surface filter comprising at least one element at a surface of the filter and electronic controls to change the optical characteristics of the element. Other methods and devices are disclosed.

Abstract: An optical modulator includes pump and signal lasers optically aligned with an optical modulator element having a nonlinear refractive index. In operation, a pulsed optical pump beam is focused inside the modulator element for obtaining oscillatory sagittal and tangential mode radii thereof. A signal beam is propagated through the focus in the modulator element at a crossing angle with the spatially modulated pump beam for phase modulation thereof. Material nonlinearity due to electronic polarization or molecular orientation provides ultrafast rise times with correspondingly high modulation bandwidth.

Abstract: An adaptive optics imaging system uses a double pumped phase conjugate mirror (DPCM) to compensate for phase, amplitude or polarization aberrations imposed upon a multi-pixel object beam. A remote reference beam is used to sample an aberrating medium through which the object beam is transmitted, and forms a shared hologram in a two-beam coupling medium with a local reference beam having known phase characteristics, generally plane-wave. An output beam is produced in the phase conjugate direction of the local reference beam, with the pixelized difference in phase characteristics between the output and local reference beams corresponding to the pixelized difference in phase characteristics between the object and remote reference beams; the remote reference beam is also preferably planar.

Abstract: Spatially variable nonlinear optical thresholding in the Fourier plane reduces signal-dependent noise, such as scalar multiplicative noise. Coherent artifact noise reduction by a factor of four is attained using deamplifying photorefractive two-beam coupling. A variable light transmittance threshold across a spatially thresholded light modulating element such as a photorefractive crystal is utilized for this purpose.

Abstract: An intensity sensitive optical switch is described which comprises a nonlinear thin film Kerr material deposited on a conducting surface.

Abstract: The optical apparatus includes first and second deflection members, a mask, a pumping light source, and a controller. The first and second deflection members are formed of nonlinear optical material whose refractive index is changed upon light radiation. The mask is arranged on an optical path extending from a front side of the first deflection member to a rear side of a second deflection member. The mask has a predetermined transmission pattern. The pumping light source radiates first and second beams on predetermined regions of the first and second deflection members. This changes the refractive indices of the predetermined regions to bend the optical path. The controller variably controls the intensity of the first and second beams.

Abstract: A 2D/3D optically controlled spatial and angular electromagnetic wave modulator is disclosed. The modulator of the present invention modulates the amplitude and direction of an electromagnetic wave such as millimeter microwaves or infrared waves by diffracting or scattering the electromagnetic wave from a semiconductor material upon which is incident a controlling lightwave. The lightwave incident upon the semiconductor is of varying intensity, and may be time varying, and changes the complex refractive permittivity of the semiconductor material. The electromagnetic wave is thus modulated in accordance with the controlling lightwave.