Abstract: This invention provides a solution for operating a mode-locking and cavity dumping laser apparatus using a single electro-optical switch or modulator, such as a Pockels cell, without the need of multiplexing between two sources of voltage. The complex waveform of electrical signal, which controls the Pockels Cell is achieved by employing the phenomena, called LC circuit ringing, where the LC circuit is formed from an inductive element and a capacitor, where the Pockels Cell works as a capacitor itself. The ringing frequency should be calculated such that the period of oscillations is preferably two times longer than the round-trip time of a light pulse inside the optical cavity. As a result, optical losses are created inside the cavity with a period, which coincides with the travel of a light pulse, thus the pulse build-up is consistent and stable.

Abstract: The ferroelectric substrate 11 of ferroelectric crystals, while being supported by the support plate 14 which is thicker than the ferroelectric substrate 11, is integrated with the support plate 14 by letting the junction 13 mediate between one major surface S1A of the ferroelectric substrate 11 and one major surface S1B of the support plate 14, and therefore, it is possible through the flat surface polishing to perform thinning of the ferroelectric substrate 11, namely, the ferroelectric crystals, and as a result, it is possible to obtain the thin periodically poled structure. By the voltage application method, the domain inverted region is formed in the ferroelectric substrate 11 which is made thin.

Abstract: An optical deflector includes multiple voltage-dependent refractive boundaries. Light passes through the refractive boundaries and accumulates a deflection angle. An electrode placed to apply a voltage to the boundaries may be non-uniform to modulate a wavefront as it passes. A scanning laser projector includes the optical deflector to modulate laser light.

Abstract: An electro-optic element includes an electro-optic crystal having a birefringent property, and in which a refractive index distribution is generated in accordance with an intensity of an electric field caused inside, a pair of intensity modulating electrodes for applying a voltage for varying the birefringent property of the electro-optic crystal, a pair of scanning electrodes for applying a voltage for varying the refractive index distribution of the electro-optic crystal, and a polarization selection member provided at least on a side of a laser beam emission end face out of a laser beam entrance end face and the laser beam emission end face of the electro-optic crystal, and for selectively transmitting a part with a specific vibration direction out of a light beam emitted from the electro-optic crystal.

Abstract: An electro-optic element includes an electro-optic crystal having a birefringent property, and in which a refractive index distribution is generated in accordance with an intensity of an electric field caused inside, a pair of intensity modulating electrodes for applying a voltage for varying the birefringent property of the electro-optic crystal, a pair of scanning electrodes for applying a voltage for varying the refractive index distribution of the electro-optic crystal, and a polarization selection member provided at least on a side of a laser beam emission end face out of a laser beam entrance end face and the laser beam emission end face of the electro-optic crystal, and for selectively transmitting a part with a specific vibration direction out of a light beam emitted from the electro-optic crystal.

Abstract: An electro-optic device includes first and second pixels that form first and second images, respectively. The first and second pixels are arranged alternately in a first direction. A light blocking element overlaps the pixels in plan view. The pixels are divided into pixel groups, each corresponding to every two pixels, which are one of the first pixels and one of the second pixels adjacent to each other in the first direction. The light blocking element has openings, each corresponding to one of the pixel groups and located in a region that overlaps the two pixels of the pixel group in plan view. Each first pixel has a light blocking region that partially intercepts light emitted from the first pixel. Each second pixel has a light blocking region that partially intercepts light emitted from the second pixel. The light blocking regions are positioned symmetrically to each other in plan view.

Abstract: An apparatus and method to operate on a light beam by using a lens that collimates the light beam to a collimated beam with at least one cross-sectional dimension less than a critical dimension of 400 ?m or less over a working range WR. The apparatus has a bulk electro-optic material of small thickness ?, e.g., less than 300 ?m positioned within working range WR and the collimated beam traverses it along its path. The apparatus has a voltage source for applying a low operating or drive voltage Vdrive, e.g. less than 400 V to the bulk electro-optic material for performing an operation on the collimated beam. The lens for collimating the light beam is a free-space collimator such as a graded index (GRIN) lens or preferably a C-lens. The apparatus is a versatile and scalable platform that can be employed in building various electro-optic devices.

Abstract: A structure includes a substrate and a light modulating film formed on top of the substrate. The light modulating film is made of polycrystalline PLZT containing Pb, Zr, Ti, and La as constituent elements. The film has a La concentration in the range of 5 at % to 30 at %. The relative dielectric constant at a frequency of 1 MHz is higher than or equal to 1200.

Abstract: An OFF state, maximum attenuation level, for an electro-optic attenuator/switch results when either a first or second control voltage is applied to the control input. An AC generator, coupled to the control input, generates minimum and maximum peak voltages that correspond to the first and second control voltages, respectively, so that the maximum attenuation level of the light beam being switched is provided by the electro-optic attenuator while either of the minimum and maximum peak voltages is applied to the control input. An ON state is achieved by introducing a voltage pulse with a magnitude corresponding to the minimum attenuation level. The ON voltage pulse is added to the square wave. This permits operation of the electro-optic switch in a normally OFF state without requiring a DC bias voltage.

Abstract: A Faraday rotator for a Faraday isolator with an input polarizer, with an output polarizer, with a roller-shaped optical crystal that is arranged therebetween and that is arranged symmetrical to its axis of symmetry, with a right hollow cylinder that surrounds this and has a hollow space made of a permanent magnetic material, which cylinder is axially magnetized and the magnetic field of which extends in the hollow space approximately parallel to the axis of symmetry that runs in only one direction from the north pole to the south pole, and with terminal magnets attached to each of the two end faces in the plane perpendicular to the y- and z-directions of the axis of symmetry, each of which is embodied as a hollow right cylinder and has a through-aperture in the extension of the axis of symmetry, is characterized in that each terminal magnet is largely radially magnetized with regard to the axis of symmetry at least by region, in that the one of the two terminal magnets is magnetized radially from interior to

Abstract: The invention discloses phase-shifters, modulators, and method that produces a smaller ? by means of a field excitation using multiple electrodes. A negative signal is introduced that travels with the positive signal, which enhances the electric field significantly. The field enhancement is provided by the superposition of the fields accumulated from each electrode. A base or substrate material can be made from any compound having linear electro-optic properties, such as lithium niobate, lithium tantalite, potassium lithium niobate, potassium titanyl phosphate or gallium-arsenide. For lithium niobate, there are two possible orientations of electric field, z-cut orientation or x-cut orientation.

Abstract: A reduced size RF signal and ground electrode interface is configured to provide better field confinement of dominant coplanar waveguide mode in the propagation direction and reduce coupling RF energy into a substrate beneath the launch, while matching the impedance of the launch to both that of the coplanar microwave electrode structure overlying the interaction region, and that of the external RF connection to the launch. In ground plane embodiments, an underlying ground plane provides better modal confinement of the dominant coplanar waveguide mode and precludes coupling of RF power to the substrate under the launch. In other embodiments, finite width electrodes provide better modal transition and mitigate against coupling to substrate modes, while providing a pad geometry that facilitates connections to external transmission line components.

Abstract: An electro-optic crystal based beam-steering device preferably based on KTN, having a first deflector and a second deflector. The first deflector has a pair of substrates each having a plurality of first electrode lines extending along a first direction and a plurality of electro-optic crystal modulators interposed between the first electrode lines. The second deflector has a pair of substrates each having a plurality of second electrode lines extending along a second direction and a plurality of electro-optic crystal modulators interposed between the second electrode lines. The first direction is orthogonal to the second direction.

Abstract: A variable semiconductor all-optical buffer and method of fabrication is provided where buffering is achieved by slowing down the optical signal using a control light source to vary the dispersion characteristic of the medium based on electromagnetically induced transparency (EIT). Photonic bandgap engineering in conjunction with strained quantum wells (QWs) and quantum dots (QDs) achieves room temperature operation of EIT. Photonic crystals are used to sharpen the spectral linewidths in a quantum well structure due to its density of states and in a quantum-dot structure caused by the inhomogeneity of the dot size, typically observed in state-of-the-art QD materials. The configuration facilitates monolithic integration of an optical buffer with an amplifier and control laser to provide advantages over other material systems as candidates for optical buffers.

Abstract: An optical interconnection device and a spot displacement device are presented. In optical interconnection device of the present invention, a spot displacement device is employed to cause a light beam to shift positions, thereby making available output positions not previously available for a light beam having bounced so few times.

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 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 is a full color printer which comprises a optical writing head for writing a latent image onto a printing paper such as a silver salt-sensitive member. The optical writing head has an array of optical shutter elements each of which is made of PLZT. Red color light, green color light, and blue color light are sequentially projected to the light shutter element, and the drive voltage applied to the light shutter elements is changed synchronized with the color change. To prevent the generation of spike noise, the drive voltage is not changed suddenly, but is changed smoothly.

Abstract: An optical modulation element is constructed of an electro-optic crystal substrate, which includes individual electrodes arrayed and formed one-dimensionally on one surface of the substrate and also includes a common electrode formed on the other surface in opposition to the plurality of individual electrodes. The portion of the electrode-optic crystal substrate, interposed between the common electrode and each the individual electrode, constitutes an aperture portion. The aperture portion is switched between a light-transmitting state and a light cut-off state by controlling voltage between the opposite electrodes. Light incident on the aperture portion in a direction perpendicular to the arrayed direction of the individual electrodes from one surface of the electro-optic crystal substrate is modulated.

Abstract: Optical plasmon-wave attenuator and modulator structures for controlling the amount of coupling between an guided optical signal and a surface plasmon wave. Optical power coupled to the plasmon wave mode is dissipated in varying amounts producing an intensity modulation effect on the optical signal. For electrical modulation, an additional dielectric (or polymer) layer with variable refractive index in optical contact with a metal layer supporting at least one plasmon wave mode is used to perturb or vary the propagation constant of plasmon wave. Propagation constant variation results in the power coupling variation between the surface plasmon wave and the optical wave. The refractive index variation of the dielectric (or polymer) layer can be accomplished via an electro-optic traveling-wave, a lump-element, or any other integrated optics modulator configuration situated to affect the layer, thereby permitting data rates into tens of GHz.

Abstract: A light control element comprising a light control layer containing an electron donating organic compound and an electron accepting organic compound and means for applying an external electric field having an intensity less than a value which is required to cause phase transition in the light control layer to the layer, wherein charge transfer excitons are produced in application of the external electric field.

Abstract: Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal.

Abstract: A high-resistance compound semiconductor 12 is epitaxially grown on a low-resistance compound semiconductor 11 and a dielectric reflecting film 13 is formed thereon, thereby forming a monolithic sensor 10. As the low-resistance compound semiconductor 11, a compound semiconductor is used which has a large bandgap so as to enable probe light to pass therethrough without being absorbed and which has a lattice constant and a thermal expansion coefficient, which are close to those of the high-resistance compound semiconductor. In addition, since the low-resistance compound semiconductor 11 also serves as an electrode, a compound semiconductor which has a resistivity of 10.sup.+1 .OMEGA.cm or less is used. Since the shorter the wavelength of the probe light used, the larger the retardation change and the larger the signal output, a compound semiconductor which has a large bandgap is used as the high-resistance compound semiconductor 12 so that light of short wavelength can be used.

Abstract: A high-resistance compound semiconductor 12 is epitaxially grown on a low-resistance compound semiconductor 11 and a dielectric reflecting film 13 is formed thereon, thereby forming a monolithic sensor 10. As the low-resistance compound semiconductor 11, a compound semiconductor is used which has a large bandgap so as to enable probe light to pass therethrough without being absorbed and which has a lattice constant and a thermal expansion coefficient, which are close to those of the high-resistance compound semiconductor. In addition, since the low-resistance compound semiconductor 11 also serves as an electrode, a compound semiconductor which has a resistivity of 10.sup.+1 .OMEGA.cm or less is used. Since the shorter the wavelength of the probe light used, the larger the retardation change and the larger the signal output, a compound semiconductor which has a large bandgap is used as the high-resistance compound semiconductor 12 so that light of short wavelength can be used.

Abstract: A cinematographic system records motion-picture images on an elongate information recording medium which includes either a charge storage layer or a light modulating layer. The recorded images are reproduced and projected onto a screen. If the charge storage layer is employed, the motion-picture images are recorded as corresponding electric charge images photoelectrically converted from optical images, and if the light modulating layer is employed, image information corresponding to the motion-picture images is recorded under an electric field depending on electric charge images photoelectrically converted from optical images.

Abstract: A charge latent image recording medium includes an electrode, a dielectric member, a member suppressing a transfer of charges, and a photoconductive member laminated in the order without any gaps therebetween. A system for reading a charge latent image recorded in a recording member includes means for projecting a first electromagnetic radiation beam along a path extending to the recording member, means projecting a second electromagnetic radiation beam approximately along the path for reading the charge latent image, guiding means disposed in the path changing electric resistance thereof along the path threthrough, in response to the first electromagnetic radiation beam projected thereto, for guiding an electric field of charges of the charge latent iamge.

Abstract: A color imaging system for use as an electronic still camera, for example, includes a color separator for separating the optical image of a subject from a lens into a plurality of different color images, an optical shutter selectively openable for transmitting the optical image of the subject to the color separator, a photoconductive layer for converting the different color images into respective electric charge images, and an information recording medium for recording images corresponding to the electric charge images under an electric field developed between the photoconductive layer and the information recording medium. The timing with which the optical shutter is opened and the timing with which the electric field is generated by the power supply, are controlled by a control unit depending on imaging conditions selected by the user. The color imaging system also has an optical viewfinder for allowing the user to visually observe the optical image of the subject introduced by the lens.

Abstract: A spatial light modulator includes an electro-optic crystal plate and a mesh electrode for capturing secondary electrons emitted from the crystal plate. Primary electrons carrying an image corresponding to an input optical image are incident on the front surface of the crystal plate to write a charge pattern thereon. In a writing operation, a dc voltage and a ramp voltage is applied to the mesh electrode and the back surface of the crystal plate, respectively. The dc voltage and a variation range of the ramp voltage are shifted to obtain a desired input/output characteristic of the device. Alternatively, a decreasing rate of the ramp voltage is changed to obtain a desired characteristic.

Abstract: A recording apparatus comprises first electrode, color-separation filter, recording, carrier generation, carrier transport, and second electrode layers which are laminated in order of mention. The recording layer and carrier generation layer may be separated at a given space. The recording layer comprises carrier retaining layer or a photo-modulation layer. Light image from an object is projected on the carrier generation layer through the first electrode, color-separation, and recording layers via an object lens enters the carrier generation layer. Carrier generated in the carrier generation layer in response to the light image are transported to the second electrode in response to application of a given voltage between the first and second electrodes. Discharge caused by application of the given voltage transfers a latent carrier image to the recording layer. The first electrode, color-separation filter and recording layers may be used for recording medium.

Abstract: A photo-to-photo transducer is composed by laminating a photoconductive layer member and a photo-modulation layer member including liquid crystals of scattering type each other and disposing the members between two transparent electrodes. The transducer is operated as follows: a specified voltage is applied across the electrodes to operate the photo-modulation layer member in the vicinity of operation threshold level thereof; an electro-magnetic radiation beam for writing information is projected onto the photoconductive layer member through the electrode at the side thereof; and an electro-magnetic radiation beam for reading the information is projected onto the photo-modulation layer member through the electrode at the side thereof, thus the electro-magnetic radiation beam for reading the information is modulated accordingly with intensity of the electro-magnetic radiation beam for writing the information.

Abstract: A light beam is chopped and split into two beams. Intensity of a first beam is changed by using, e.g., an electrooptic material in accordance of a change in a signal to be detected, such as a voltage in an electronic device, and detected by a first photodetector. On the other hand, a second beam is detected by a second photodetector without being subjected to the intensity change. At least one of the outputs of the first and second photodetectors are adjusted so that they become equal to each other when no signal is applied to the light intensity changing means. The difference of the thus adjusted output signals is detected by, e.g., a lock-in amplifier in a narrow band at the chopping frequency.

Abstract: An apparatus for processing information carried by an electro-magnetic radiation beam. The apparatus includes a charge holding member for storing a charge latent image, a generator for generating an electro-magnetic radiation beam which is a superimposition of a plurality of electro-magnetic radiation beams with different wavelength ranges, a filter for separating the superimposed beam into the plurality of electro-magnetic radiation beams and a photo-conductive member provided adjacent to the charge latent image holding member and having an impedance which varies according to the intensity of each of the plurality of beams separated by the filter. Charge latent images corresponding to each of the plurality of beams are thus recorded on the charge latent image holding member. The charge latent images thus recorded on the charge latent image holding member are reproduced by means of a photo-modulation member provided instead of a photo-conductive member.

Abstract: There is provided an apparatus for reproducing a charge latent image prerecorded on a recording medium composed of at least a photo-modulation layer and a charge holding layer laminated thereto and holding said charge latent image. The apparatus has two electrodes interposing the recording medium therebetween. The electrodes are connected to each other and one of which is spaced from the recording medium. A reading light is allowed to permeate the photo-modulation layer. The apparatus also has a vibrator which vibrates one of the electrodes to modulate an electric field generated between the electrodes by the charge latent image prerecorded on the recording medium. The reading light is then electro-optically modulated to reproduce the charge latent image.

Abstract: There is provided a recording medium for recording information in a form of a charge latent image. The recording medium comprises, at least, an electrode through which an electro-magnetic radiation beam passes, a photo-conductive layer (hereinafter abbreviated in a PCL) whose resistance varies when the beam is applied thereto and an insulation layer (hereinafter abbreviated in an IL), the electrode and the layers being laminated to each other. There is further provided an apparatus for recording an image as a charge latent image on the medium described above. The apparatus comprises a guide for guiding an electro-magnetic radiation beam through the electrode, an auxiliary electrode arrangeed to face the madium so as to interpose the PCL and the IL between the electrodes and an unit for applying an electric field across the electrodes. There is still further provided an apparatus for reproducing information prerecorded as a charge latent image on the medium.

Abstract: A contrast enhancing, substantially transparent touch panel device comprises a static element, a dynamic element and a microweave screen of a fine mesh of fine dark-colored filaments embedded within a clear adhesive layer and incorporated as an integral part of the dynamic element of the panel. Preferably there is no air gap between the front of the device and the conductive surface of the dynamic element. The device can comprise at least one layer of transparent colored coating for light attentuation, color-selective light filtering, and tint correction.