Abstract: A semiconductor device capable of producing a multiwavelength laser effect comprising a substrate having thereon at least two double heterostructure stacks, each stack comprising at least one active layer bounded by two confinement layers, the stacks being in the form of elongated strips disposed side-by-side, electrically insulated from each other. Each stack comprises a P-N junction therein which is individually and electrically operable and which is situated in the vicinity of an active layer of a different composition and rank in each stack. The transverse opposite ends of the strips are optically prepared and the upper surfaces of the strips form an upper surface for the device which is substantially flat.

Abstract: A flat panel display system is provided in which the pixels thereof are illuminated by optical fibers. Economy and compactness are achieved by using micromechanical light modulators to demultiplex light from a limited number of LED's to a large number of pixels. By using micromechanical light modulators incorporated in an integrated circuit, the flat panel display system is relatively economical, has low power consumption, and produces a display of very high resolution. The display also may be provided in full color.

Abstract: An electro-optical device comprising a CCD structure having charge wells, the charges therein being controlled by a modulating signal applied to said CCD structure. A multiple quantum well structure having quantum well regions associated with the charge wells of said CCD structure, the charges in the CCD charge wells determining the value of the electric fields at said quantum well regions and, hence, the electro-absorption effects at said quantum well regions. The intensity of an input electromagnetic wave signal directed through said electro-optical device is thereby spatially modulated by the electro-absorption effects at the quantum well regions of the multiple quantum well structure. A novel CCD structure using quantum well regions to form the charge wells thereof can be used as the CCD structure for controlling the electric fields at the multiple quantum well structure.

Abstract: A light-controlled semiconductor light coupler for altering the position of and modulating a signal light in response to the intensity of a control light includes a multiple quantum well structure having an index of refraction that varies in response to the intensity of an incident, essentially monochromatic control light, first and second semiconductor light guide layers contacting and sandwiching the multiple quantum well structure for transmitting a signal light beam variably coupled between the first and second light guide layers in response to the intensity of the control light, and first and second semiconductor cladding layers contacting and sandwiching the first and second light guide layers, respectively.

Abstract: A semiconductor laser which includes a controllable beam splitter has three segments including laser-active zones and a monitor diode forming a cross-shaped laser connected with one another by way of the beam splitter. The beam splitter is equipped with electrodes for controlling optical coupling between the segments.

Abstract: A Doppler velocimeter for measuring the doppler frequency shift of light scattered from particles suspended in a medium. The velocimeter includes a light source and an integrated optical waveguide having a first optical waveguide path for receiving an incident beam of light from the light source at one end. The first waveguide path further guides the incident beam to a second end which is located in the medium adjacent the particles. A second optical waveguide path is optically coupled to the first waveguide path for receiving the scattered light from the particles as well as the non-scattered light and guiding both to the other end thereof. A detector receives the scattered and non-scattered light from the second waveguide and converts it to an electrical signal indicative of the doppler frequency shift.

Abstract: A fully integrated electro-optic page-scanner comprises an optically transparent waveguide made from an electro-optic polymer, and an electrode structure including a linear array of electrically-addressable, spaced, parallel electrodes for selectively altering the refractive index across pixel-sized portions of the polymeric waveguide. According to the invention, the addressable electrodes are disposed on a photoconductive substrate which facilitates poling of the polymer waveguide to rander it electro-optic in nature. During the poling process, the photoconductive substrate is made electrically conductive by flood illumination, while a uniform electric field is established between the substrate and a transparent electrode which overlies the waveguide layer, opposite the addressable electrodes. Preferably, the photoconductive substrate comprises undoped silicon which enables certain electrode-addressing circuitry to be integrated within the scanner structure.

Abstract: A buried-heterostructure laser modulator for modulating a laser beam includes two adjacent thin epitaxial first layers of oppositely doped semi-conductor material and a thin epitaxial buried layer of undoped semi-conductor material located between the two adjacent first layers. The buried layer forms a single mode optical channel having a width larger than a height thereof with the width equal to or greater than a width of a diffraction limited waveguide mode of the laser beam. Two thin epitaxial second layers of similarly and heavily doped semiconductor material are provided respectively adjacent the respective first layers of the same doping. One of these second layers is provided on a side of a semi-insulating substrate and two strip lines of opposite bias are provided on the side of the substrate and connect to a respective second layer of the same bias. The two adjacent first layers are preferably AlGaAs and the buried layer is preferably GaAs with a width less than about 1.

Abstract: A polarization independent guided wave semiconductor device is realized wherein the waveguide region of the device includes one or more strained quantum well layers wherein strain is designed to be tensile in nature so that energy subbands in the quantum well or wells are displaced by a predetermined amount in a direction opposite to that for the quantum size effect. Polarization independence is achieved when, for a lightwave signal having an incident mean photon energy below the absorption bandedge of the strained quantum well layer or layers, the ratio of the oscillator strengths versus the wavelength detuning for heavy and light holes in a first polarization (TE) is substantially equal to a similar ratio computed in a second polarization (TM). Wavelength detuning is understood to be the difference between the wavelength of operation and the wavelength of an exciton resonance peak. Passive and active or actively controllable waveguides and waveguide devices are described.

Abstract: An electro-optic waveguide device (10) comprises an assembly of waveguides (30) connected to a common light input region (41) and forming a common far field diffraction pattern (44). The device (10) comprises an n.sup.+ GaAs substrate (14) bearing a waveguide lower cladding layer (16) of n.sup.+ Ga.sub.0.9 Al.sub.0.1 As, which is in turn surmounted by a waveguide core layer (18) of n.sup.- GaAs. The layer (18) has grooves (20) defining the waveguides (30), each of which has a respective Schottky contact (32). Each contact (32) is biased negative with respect to the substrate (14), which reverse biases the respective Schottky diode waveguide structure. The waveguide core layer (18) has electro-optic properties, and its refractive index varies with electric field. The phase of light emerging from each waveguide is therefore independently variable by means of its applied bias voltage.

Abstract: An optical article is disclosed containing, for the transmission of electromagnetic radiation, a medium exhibiting a second order polarization susceptibility greater than 10.sup.-9 electrostatic units comprised of a linear polymer containing polar aligned noncentrosymmetric molecular dipoles having an electron donor moiety linked through a conjugated .pi. bonding system to an electron acceptor moiety to permit oscillation of the molecular dipole between a ground state exhibiting a first dipole moment and an excited state exhibiting a differing dipole moment. The linear polymer is a condensation polymer including in its backbone a plurality of molecular dipoles including sulfonyl electron acceptor moieties sequentially arranged to reinforce electron displacement along the polymer backbone.

Abstract: An optical article capable of modulating the reflection of polarized monochromatic electromagnetic radiation is disclosed comprising a reflective metal layer having a thickness of less than 0.5 .mu.m, means acting as a support for directing polarized electromagnetic radiation to the reflective metal layer, a dielectric layer interposed between the support and the reflective metal layer having a refractive index less than that of the support and a thickness in the range of from 0.1 to 10 times the wavelength of electromagnetic radiation directed toward the reflective metal layer, an electrooptic medium that exhibits a refractive index which is a function of an applied electrical potential, and a counter electrode. The optical article is characterized in that it is capable of modulating the reflection of polarized monochromatic electromagnetic radiation from differing wavelength sources to produce a multicolor image.

Abstract: An Electro-Optic modulation method and device using a low-energy oblique transition of a tightly coupled super-grid. According to the present invention, a luminous beam is injected into a tightly coupled super-grid and an electric field (E) is applied to the super-grid whose amplitude is made to gradually vary so as to cause the intensity of the beam to vary. This beam is injected parallel to the plane of the films of the super-grid which guides the injected beam. The electric field is weak and applied along the growth direction of the super-grid, which provokes the appearance of a low energy oblique transition (TB) in a domain of wavelengths where the super-grid is transparent in the absence of any electric field. The super-grid is one whereby the wavelength of the luminous beam is contained in this domain. Such a device may find application in optical telecommunications systems.

Abstract: A system for dynamically steering a light beam alters the path of a light beam using refraction. The light beam passes through multiple layers of optically transparent elastic material. Electrodes are attached to the bottom and top surfaces of the optically transparent layers. Voltages applied to the electrodes cause the optically transparent layers to deform. This deformation causes a change in the angle at which the light beam intercepts the surfaces of the optically transparent layers. The light beam is refracted based upon the angle of intercept and the index of refraction of the optically transparent layers. The direction of travel of the light beam can thus be controlled by varying the voltages across the electrodes.

Abstract: This invention enables low voltage operation and improves matching in velocities of the radio frequency and of light by lowering effective index and to thereby expand modulation frequency bandwidth by structuring an optical modulator where a substrate of the material of which refractive index changes by an application of electric field description, and the insulating buffer layers are eliminated from the regions other than the electrodes. By structuring the modulator in a manner to satisfy the prescribed conditions with dimensions of each unit, the light can be matched in complete phase matching (group velocity matching) with radio frequency while characteristic impedance of the electrodes is fixed at a desired value.

Abstract: The invention relates to an integrated optical polarization splitter based on the mode filter principle, in which the asymmetry, necessary therefor, of the waveguides is obtained by using a polable glassy polymer as optical waveguide material, which material is polarization-sensitive in the poled state and is not, or virtually not polarization-sensitive in the unpoled state. A Y-shaped optical waveguide pattern 8 of polable glassy polymer comprises a continuous optical waveguide formed by the optical waveguide sections 8.1 (incoming) and 8.2 (outgoing) in which the polymer is in the unpoled state and an outgoing optical waveguide section 8.3 which connects to said optical waveguide at an acute angle and in a tapered fashion and in which the polymer is in the poled state. Since the poled material is also electro-optical, an electric field, for example generated between electrodes 2 and 10, can still correct any small deviations in the asymmetry.

Abstract: A fully integrated electro-optic page-scanner comprises an optically-transparent waveguide made from an electro-optic polymer, and a linear array of electrically-addressable, spaced, parallel electrodes for selectively altering the refractive index across pixel-sized portions of the polymeric waveguide. Parallel addressing of the electrodes in accordance with the intensity pattern of a line of pixels to be recorded acts to modulate the phase front of an optical wave propagating within the waveguide in accordance with such line intensity pattern. Schlieren optics, also integrated with the page-scanner, convert the phase-front-modulated wave to an intensity-modulated pixel pattern which can be imaged onto a moving photosensitive recording element to record a two-dimensional (page) of image information. By using an electro-optic polymer as the waveguide, certain disadvantages of prior art scanning devices are eliminated.