Abstract: An apparatus and method for modulating a phase of optical beam. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of semiconductor material disposed in a second region of semiconductor material. An insulating region is disposed between the first and second regions of semiconductor material defining a plurality of interfaces between the insulating region and the first and second regions of semiconductor material. An angle of incidence between an optical beam and the plurality of interfaces is substantially equal to Brewster's angle. A plurality of charge modulated regions proximate to the plurality of interfaces in the first and second regions of semiconductor are included such that the optical beam directed through the plurality of interfaces and the plurality of charge modulated regions is phase shifted in response to the plurality of charge modulated regions.

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: Apparatus for wavelength conversion includes a first optical be splitter, a first leg and a second leg each splitting from the first optical beam splitter, a first optically passive nonlinear device disposed in the first leg, a second optically passive nonlinear device disposed in the second leg and a second optical beam splitter joining the two legs beyond the optically passive nonlinear devices. An unmodulated optical signal splits between the two legs. When no other beam is in the second leg, all optical signals exit the second beam splitter at a first port. When another (modulated) beam is imparted to the optically passive nonlinear device in the second leg, an imbalance is created at the second beam splitter such that some portion of the unmodulated optical signal exits at a second port of the second beam splitter in a modulated manner.

Abstract: High precision optical components, for example CaF2 lenses in lithographic systems for the production of integrated circuits, often suffer from stress induced birefringence and other imperfections. For altering the optical properties in a confined region of the optical component, the latter is exposed to a beam of ions having an energy preferably in the order 100 MeV/u. This results in a modification of the optical properties due to an interaction of the ions with the surrounding medium the optical component consists of. By carefully choosing the parameters of the process, it is possible to alter the refractive index or the mechanical stress distribution or other optical properties within a confined region of this medium.

Abstract: The present invention pertains to an optical shutter comprising an organic free radical compound, wherein the optical shutter is reversibly imageable to switch between a non-reflective and transparent state and a reflective state. This switching may be induced by the absorption of photons, the application of an electric current, or thermally. Preferably, the organic free radical compound is a salt of an aminium radical cation. Also provided are optical switch devices and optical buffers comprising such optical shutters, methods of switching an optical signal utilizing such optical shutters and switch devices, and methods of storing an optical signal utilizing such optical buffers.

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 optical sampler based on stable, non-absorbing optical hard limiters includes an optical feedback loop for storing an optical signal in optical form. The optical feedback loop includes appropriate components for amplifying/reproducing the stored optical signal. The optical sampler outputs the stored optical signal.

Abstract: A method of and/or device for writing to an optical modulator using electromagnetic write beams, the modulator having a photorefractive converter body in which the space-modulated write beam may induce changes in the refractive index. An external voltage may be applied to the converter body. The intensity of the external voltage may be selected within a voltage range in which the buildup of changes in the refractive index may be accelerated by an increase in the charge carrier mobility or charge carrier density.

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 when viewed in the cross section of the modulating region. 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 between the adjacent thicker parts.

Abstract: A system (10) for optical processing based on light-controlled photon tunneling is provided. The system (10) includes a prism (12) having a metallic film layer (14) formed on an upper surface thereof. The metallic film layer (14) has a microscopic aperture (18) formed therethrough and the microscopic aperture (18) is covered by a layer of non-linear optical film. A first light beam (30) is projected towards aperture (18) and photons from first light beam (30) tunnel through aperture (18). A second light beam (32) is also projected towards microscopic aperture (18), with the second light beam (32) having a different wavelength than that of light beam (30). Selective actuation and modulation of light beam (32) allows for selective control over the rate and intensity of the photons which tunnel through microscopic aperture (18).

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: Describes novel polyfunctional thiiranes. Also described are polymerizable compositions comprising such novel polyfunctional thiiranes, and polymerizates, e.g., optical lenses, prepared therefrom. The described polymerizates may have a refractive index of at least 1.6, and an Abbe number of at least 27.

Abstract: An electro-optic interconnect for use with optical signals and a probe beam is disclosed. A plurality of first optoelectronic detectors responds to an optical signal and develops a plurality of first electrical signals. A probe laser generates the probe beam. Means are responsive to the plurality of first electrical signals and changes a characteristic of the optical probe beam. A second optoelectronic detector responds to the changed characteristic and develops an output electrical signal representative of the optical signals. Alternatively, the second optoelectronic detector can be eliminated and direct optical signal processing can be implemented. In another aspect, a time compensation network serves to synchronize the probe and the signal beams. The electro-optic interconnect can be configured to add and subtract the optical signals.

Abstract: An adaptive pulse compressor is described, especially for use with ultrashort pulses, wherein the input pulses are modified in an iterative fashion, according to a feedback signal obtained from measurement of the output pulses. The feedback signal is programmed, by means of a programmable spatial light modulator, to allow for independent control of the individual spectral components of the incoming pulses, such that almost arbitrary phase functions can be realized to accomplish efficient compression. One of the main disadvantages associated with prior art pulse compressors, namely, the need for characterization of the uncompressed pulses, is thus eliminated. The compressor is thus capable of handling completely uncharacterized or partially characterized input pulses, or pulses from time varying sources.

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: Novel naphthopyrans having an oxygen-containing heterocyclic group F annelated on the f, i, j, or k side of the naphthopyran ring. These naphthopyrans may have the formula (I) presented below: These compounds (I) have interesting photochromic properties. Various organic host materials that contain such compounds are described. Articles such as ophthalmic lenses or other plastic transparencies that incorporate the novel naphthopyran compounds or combinations are enabled.

Abstract: The present invention pertains to an optical shutter comprising an organic free compound, preferably a radical cation or a radical anion, wherein the organic free radical compound forms an oxidized or a reduced product having a change in absorption in a near-infrared or a visible wavelength region as a result of a photo-induced electron transfer reaction of the free radical compound. Preferably, the photo-induced electron transfer reaction occurs in less than 0.1 nanoseconds after absorption of photons by the free radical compound. Also, preferably, the change in absorption is reversible and occurs in less than 10 milliseconds. Also provided is an optical shutter for use as an optical switch in fiber optic communications, and, alternatively, for use in a laser protection device, a security protection system, and an eyewear device.

Abstract: The present invention pertains to an optical shutter comprising a 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: An optical switch includes a saturable absorber. Coupled to the saturable absorber is an input waveguide, an output waveguide, and a control beam waveguide. In the absence of light input to the control beam waveguide, the saturable absorber prevents an input signal on the input waveguide from passing through and being output on the output waveguide, thus placing the switch in an “off” state. In the presence of light input to the control beam waveguide and incident of the saturable absorber, the saturable absorber allows the input signal to pass through and be output on the output waveguide, thus placing the switch in an “on” state.

Abstract: An intensity filter for deep UV lithography enhances contrast and also therefore increases the resolution of patterned images by passing only intensities that fall within a specific minimum threshold value, resulting in a more exact aerial image replicating the mask image. This device is a different approach to contrast enhancement that is distinguished from previous methods by eliminating the need for an extra layer of contrast enhancement on top of the resist, thereby reducing the number of processing steps in semiconductor fabrication.

Abstract: The present invention pertains to an optical shutter comprising an organic free compound, such as a radical cation or a radical anion, and a polydiacetylene compound, wherein the polydiacetylene compound is characterized by having a change in absorption in a wavelength region as a result of a photo-induced heat transfer from the free radical compound. The thermochromic change in absorption is reversed by thermal cooling or by a photo-induced reaction after the photo-induced heat transfer. Also provided is an optical shutter for use as an optical switch in fiber optic communications, and, alternatively, for use in a laser protection device, in a security protection system, or in an eyewear device.

Abstract: An optical inverting system employs a first optical structure having an index of refraction that varies with the intensity of an incident beam and a second optical structure having a constant index of refraction, and forming an interface therebetween. An optical pulse stream is combined with a laser beam and the combined beam is applied to the first optical structure, impinging the interface at a predetermined angle of incidence. If the angle of incidence is less than a critical angle, the beam is refracted into the second optical structure. If the angle of incidence is greater than the critical angle, the beam is completely reflected at the interface. Thus the output of the second optical structure is an inversion, and the output of the first optical structure is a level shifted replica, of the optical digital pulse stream.

Abstract: An optical transmission system having an optical regeneration circuit for regenerating a signal with a deteriorated signal to noise ratio. A signal light at wavelength &lgr;1 which includes a noise light is composed with a continuous light at wavelength &lgr;2 outputted from a light source to obtain a composed signal light in an optical coupler. The composed signal light is passed through a saturable absorption type optical element which transmits only the signal light having a light intensity equal to or greater than a threshold value, thereby removing the included noise light. From the signal light, only the signal at the same wavelength &lgr;2 as the wavelength of the continuous light is extracted by a wavelength divider and data signal of the incident signal light is replicated in the continuous light and outputted. Thus, a signal light having no deterioration of the signal to noise ratio at wavelength &lgr;2 can be regenerated from the signal light having the deteriorated signal to noise ratio.

Abstract: The thermo-optic behavior of an optical path over a range of temperatures &Dgr;T is controlled by determining a figure-of-merit (FOM) for the optical path and including in the path a body of crystalline material that enables the conditions specified by the FOM to be satisfied. The crystalline material is highly transparent at a wavelength &lgr; of radiation propagating in the path, and it has a coefficient of thermal expansion (CTE) and a refractive index n such that the CTE and dn/dT are mutually adapted to satisfy the FOM over the range &Dgr;T. In one embodiment, the CTE and dn/dT of an etalon compensate one another so as to perform frequency discrimination that is essentially temperature insensitive over the range &Dgr;T. In a preferred embodiment of the optical etalon the crystalline material comprises LiCaAlF6.

Abstract: The present invention pertains to an optical shutter comprising an organic free radical compound, wherein the optical shutter is reversibly imageable to switch between a non-reflective and transparent state and a reflective state. This switching may be induced by the absorption of photons, the application of an electric current, or thermally. Preferably, the organic free radical compound is a salt of an aminium radical cation. Also provided are optical switch devices and optical buffers comprising such optical shutters, methods of switching an optical signal utilizing such optical shutters and switch devices, and methods of storing an optical signal utilizing such optical buffers.

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: A method for applying a bus bar to the peripheral edge region of a shaped substrate is disclosed. The method involves: 1) applying a protective coating to a blank substrate; 2) edging the blank substrate to shape; 3) applying a conductive coating to the peripheral edge region of the shaped substrate; and 4) removing the protective coating, along with excess conductive material.

Abstract: An opto-mechanical device is constituted by an optically responsive actuating member in which a mechanical strain occurs in response to changes in its illumination. The actuating member is preferably at least partly formed from a semiconducting glassy matrix such as a chalcogenide glass. Preferably the opto-mechanical device illuminates the actuating member with light which is preferably plane polarized. Preferably it also varies the polarization angle of the plane polarized light to cause a change in the strain generated in the actuating member.

Abstract: The object of the present invention is novel photochromic [indole]naphthopyran compounds and their methods of preparation.

Abstract: The present invention pertains to an optical shutter comprising an organic free compound, preferably a radical cation or a radical anion, wherein the organic free radical compound forms a reaction product having a change in absorption in a near-infrared or a wavelength region as a result of a photo-induced reaction of the free radical compound. Preferably, the photo-induced reaction occurs in less than 0.1 nanoseconds after absorption of photons by the free radical compound. Also, preferably, the change in absorption is reversible, and the optical shutter is reversibly imaged in less than 10 milliseconds to regenerate the free radical compound. Provided is an optical shutter for use as an optical switch in fiber optic communications, and, alternatively, for use in a laser protection device, a security protection system, and an eyewear device. Also provided are optical switch arrays, optical buffers, optical routers, and tunable optical gain filters comprising such optical shutters.

Abstract: A high contrast ultrahigh speed optically-addressed ultraviolet light modulator exploits the optical anisotropy in a ZnO film epitaxially grown on (01 {overscore (1)}2) sapphire. This device, which could also be realized in a ZnO bulk crystal or similar wide bandgap material, achieves both high contrast and high speed by exploiting the anisotropic bleaching of the anisotropic absorption and concomitant ultrafast polarization rotation near the lowest exciton resonances produced by femtosecond ultraviolet pulses. The resultant modulation in a preferred embodiment is characterized by a contrast ratio of 70:1, corresponding to a dynamic polarization rotation of 12°, and decays to a quasi-equilibrium value within 100 ps.

Abstract: The present invention provides an optical function device which is capable of inverting and amplifying an optical signal of the optical communication wavelength band, and executing operation of an image optical signal, and is operable in a wide temperature range, said optical function device composed of a light transmitting medium containing a rare earth element, comprising a portion thereof doped with 1×1023 per 1 m3 or more of the rare earth element for inverting an optical signal and a portion thereof doped with 1×1021 per 1 m3 or more of the rare earth element for amplifying the optical signal with an excitation light superposed thereto.

Abstract: An optical pulse observing device enables the clear observation of indirect laser light of pulse laser light. The optical pulse observing device to be used by a user for observing pulse illumination light directly or indirectly, includes an optical shutter means that operates for alternate opening and closing in synchronism with periodic pulses of the pulse laser light so as to open only during the duration of pulses of the pulse laser light to pass pulse laser light and external light.

Abstract: An adjusting apparatus is provided, in particular, for the adjustment of a lens in an optoelectronic transmitting/receiving device, has a number of actuating elements or actuators, whose form or whose length can be altered by local application of radiation energy, preferably as laser radiation. The actuating elements are connected to a stationary base plate at one of their ends and connected to a movable carrier plate at their other end. The actuating elements can be disposed in such a way that they enable coarse adjustment and subsequent fine adjustment by the laser beam.

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: An optoelectronic shutter for radiation, comprising an input plate and an output plate, comprising material substantially transparent to the radiation, each plate having an outer and an inner surface, wherein a recess is formed in the inner surface of at least one of the plates, and wherein respective non-recessed portions of the inner surfaces of the plates are bonded together, and the recess defines a vacuum chamber enclosed by the two plates; a photocathode fixed to the inner surface of the input plate, adjacent the chamber, and a photo-emissive anode, fixed to the inner surface of the output plate, adjacent the chamber and opposite the photocathode.

Abstract: An adaptive pulse compressor is described, especially for use with ultrashort pulses, wherein the input pulses are modified in an iterative fashion, according to a feedback signal obtained from measurement of the output pulses. The feedback signal is programmed, by means of a programmable spatial light modulator, to allow for independent control of the individual spectral components of the incoming pulses, such that almost arbitrary phase functions can be realized to accomplish efficient compression. One of the main disadvantages associated with prior art pulse compressors, namely, the need for characterization of the uncompressed pulses, is thus eliminated. The compressor is thus capable of handling completely uncharacterized or from time varying sources.

Abstract: A simple mathematical model, given below, is constructed on the premise that reflected light other than light reflected at a metal surface is quantitatively taken into consideration the device to which the present invention is applied is a multilayer structure with a refractive index difference, so that only one reflection at an interface other than the metal surface can be taken into account that is, two or more reflections can be neglected. Further the concept of localized light emitting surfaces is extended to a non-localized model. The below simple mathematical model is used to treat reflected wave components so that an accurate simulation can be run.

Abstract: An optical switch with simple circuit structure and increased a response speed is disclosed. This optical switch comprises a light combiner for combining a light signal &lgr;S and a control light &lgr;C and outputting a combined signal, and a saturable absorption type optical device provided with an input port and an output port, and outputs a light signal based on the combined light signal outputted from the light combiner. When an input power of the light signal &lgr;S is at a region where a light signal applied to the saturation absorption type optical device is attenuated, the light intensity of the control signal &lgr;C is set to the OFF state, and when the input power of the light signal &lgr;S is at a region where a light signal applied to said saturation absorption type optical device transmits therethrough, the light intensity of said control signal &lgr;C is set to the ON state.

Abstract: The main aim of the present invention is a method of preparing photochromic or non-photochromic organic pieces of optical quality and especially organic lenses, by radical polymerisation of a mixture of radically polymerisable monomers, characterised in that it comprises: a) adjusting, by pre-polymerisation, the viscosity of said mixture, to a value between 0.4 and 2 Pa.s; b) pouring said pre-polymerised mixture into a mould; c) photogelifying, in said mould, said pre-polymerised mixture until its gel point; d) completing the polymerisation of said pre-polymerised and gelified mixture in said mould, by heat treatment; adding effective amounts of at least one thermal catalyst and of at least one photoinitiator intervening in said mixture of monomers for the implementation of said pre-polymerisation, photogelification and polymerisation; said photoinitiator(s) intervening in an amount less than or equal to 0.009 parts by weight per 100 parts by weight of said mixture of monomers.

Abstract: Inorganic crystals having one or more species of dopant ions which are photo-reactive are used as visible and or infrared light optical limiters to protect against laser radiation exposure while permitting passage of the visible and or infrared light spectrum at least until exposed to high energy laser radiation. The dopant ions are selected from ions of transition metals. The exposure of these ions within the transparent crystalline matrix either photo-ionize or are elevated to an excited state and thereby absorb or otherwise attenuate the passage of the laser beam radiation sufficiently to protect human eyes or photo-sensitive equipment. The crystals may be fabricated into such items as lenses for use in eyeglasses or on shields of flight helmets to protect the eyes of aircraft pilots.

Abstract: An optical-fiber-amplifier measuring apparatus includes: a light source 14 for measuring various characteristics of an optical fiber amplifier 22 to be measured; an acoustooptic modulator 16 for modulating an optical signal inputted from the light source 14 to the optical fiber amplifier 22 to be measured; a light source 10 for setting the optical fiber amplifier 22 to be measured in a saturated state; and an acoustooptic modulator 12 for modulating an optical signal inputted from the light source 10 to the optical fiber amplifier 22 to be measured.

Abstract: An optical switch includes a saturable absorption type optical element provided with a saturable absorption region, and a band-block optical filter to which signal light composed of at least one wavelength light having an optical power in the absorption region of the saturable absorption type optical element and control light whose optical power is set such that a total power of the signal light and the control light comes within a transmission region of the saturable absorption type optical element and which is composed of either one of two wavelength lights different from that of the signal light are inputted and which transmits therethrough the signal light and the control light which is composed only of one of the wavelength lights and outputs the transmitted signal light and control light to the saturable absorption type-optical element. ON/OFF of the signal light is controlled by varying the wavelength of the control light.

Abstract: An MFA-MOPA that includes a semiconductor laser with separate master oscillator and trumpet-flared power amplifier regions. Within the trumpet-flared active gain region of the uniformly-pumped power amplifier of the MFA-MOPA device, the density distribution of carriers and reflections of the laser beam are analyzed to determine the output powers at which filamentation and beam degradation due to reflections occur. The shape of the trumpet-flare is optimized to delay the onset of filamentation and the degradation of the output laser beam due to reflections to higher output powers for the MFA-MOPA device.

Abstract: A procedure is disclosed for assembly of novel two-sided monolayer or multilayer device architectures out of self-assembly or self-organizing amphiphilic compounds derived from molecules that undergo a type of valence tautomerization known as asymmetric narcissistic reactions. The two-sided monolayer architectures are constructed by Langmuir-Blodgett (LB) transfer or self-assembly (SA) techniques while the multilayer architectures are formed by Y-type LB depositions, where the two layers or bilayers of the assemblies are alternate depositions of mirror-image forms of the amphiphiles. The resulting three-dimensional supramolecular assemblies described herein are uniquely capable of commutation between two non-centrosymmetric states which have, on a macroscopic scale, an optically antipodal relationship and a third central symmetric state which is, accordingly, optically racemic.

Abstract: A light-modulating element having a RQB medium, a pair of electrodes provided on the RQB medium and connected to a high-frequency power supply, a signal light source for emitting two signal light beams, and two optical fibers for guiding the signal light beams to the RQB medium. In the element, the conditions .sigma..sub.23 .ltoreq..sigma..sub.12 and .sigma..sub.23 .ltoreq..sigma..sub.13 are satisfied, where .sigma..sub.12 is the standard deviation (inhomogeneous broadening) of energies of impurities between a first level and a second level, .sigma..sub.13 is the standard deviation (inhomogeneous broadening) of energies of impurities between first level and a third level, and .sigma..sub.23 is the standard deviation (inhomogeneous broadening) of energies of impurities between the second and third levels, all impurities existing in the RQB medium.

Abstract: An optical processor comprising, a semiconductor saturable absorber; a current source for injecting a current to the semiconductor saturable absorber; a signal light introducer for introducing a signal light to the saturable absorber; a control light introducer for introducing a control light having a wavelength not longer than the wavelength of the signal light into the semiconductor saturable absorber; an assist light introducer for introducing an assist light having a wavelength longer than the wavelength of the signal light into the semiconductor saturable absorber; and a signal light extractor for extracting the signal light after treatment by the semiconductor saturable absorber.

Abstract: An optically addressed spatial light modulator (OASLM), and an optical pattern processor employing the same. An embodiment of the OASLM includes a transparent electrode; a buffer layer; a detector region; and a modulator region, wherein the detector and modulator regions are optically isolated and resist electron movement therebetween. In one embodiment, the detector region includes a photoconductive semiconductor region with a higher band gap than the modulator region and the modulator region comprises a low-photoconductive semiconductor material.

Abstract: An optical modulator according to the present invention comprises an optical guide region including a quantum well layer, a waveguide structure defining an optical path of the guide region, a gate situated below the guide region for changing the carrier density in the quantum well layer, an electrical contact for said gate and at least one other electrical contact.

Abstract: A light-transmissible article formed from a polymeric material, which article includes at least one photochromic dye; and a compatible light absorbing material distributed on or within the article; the combination of photochromic dye and compatible light absorbing material is such that the depth of darkening upon activation of photochromic dye is rendered substantially uniform regardless of variations in length, thickness or local changes of surface shape.