Abstract: Optical laser amplifier devices are formed integrally with spontaneous emission filters. The filtering function is accomplished by a laser amplifier whose output is employed to quench the signal generated by a laser. The quenching of the laser is performed in direct proportion to the stimulated emission component of the laser amplifier output signal. Since the stimulated emission component represents the output signal minus any spontaneous emission noise, the output signal generated by the laser is an amplified, inverted version of the input signal without the noise components. In the preferred embodiments, optical waveguides are employed to form the laser amplifier and the laser is either a horizontal cavity edge emitting laser or a vertical cavity surface emitting laser (VCSEL).

Abstract: Intrapulse Raman scattering is utilized in providing optical devices that can be adapted to perform various logic and switching functions. In a logic gate embodiment of the present invention, a plurality of pulses of the same central wavelength are coupled to produce an output pulse having a power level equal to the sum power level of the inputs. When the power level of a sufficiently narrow output pulse exceeds the Raman threshold, the output pulse experiences a wavelength shift of a magnitude that can be controlled by adjusting the input power. An optical filter selectively blocks coupler output pulses depending on the desired logical operation of the device. In a switch according to the invention, an input pulse and a control pulse are coupled, and Raman scattering of the output pulse is stimulated. The output pulse is applied to several output lines, each having a filter centered at a predetermined pass band.

Abstract: A means, method and apparatus for dual-phase amplification of wave-type signals is disclosed comprising superimposing a constant level beam set and a modulated beam set to produce a first interference image at first and second locations. A first image component separator separates energy from constructive and destructive interference component regions to produce secondary beam sets that are combined to produce a second interference image, which is separated at a destructive interference region to produce the output. The amplifier with multiple inputs is then connected in cascade, as a phase-bistable device, as a level detector, an AND, an OR, and/or a synchronized oscillator. Multiple frequencies work independently, allowing for frequency-multiplexed functions.

Abstract: An all-optical flip-flop device is achieved by employing two optical amplifiers arranged so that they together operate in only one of two stable states at a given time. In a first stable state of operation, the first optical amplifier behaves as a laser having a first predetermined characteristic wavelength. The arrangement is switched to a second stable state of operation in which the second optical amplifier behaves as a laser having a second characteristic wavelength, where the first and second characteristic wavelengths are at least nominally different, when an optical signal pulse is received at the input of the first optical amplifier. The arrangement is switched back to the first stable state when an optical signal pulse is received at the input of the second optical amplifier.

Abstract: An optoelectronic computer graphics system is disclosed wherein Optoelectronic Integrated Circuits (OEICs) and computer generated holograms are used to construct a final image by optically assembling a plurality of primitive image portions into the final image. The primitive portions of the final image are stored in a hologram. An optoelectronic integrated circuit means is controlled to select, and then assemble, the necessary primitive images to form the final image.

Abstract: The present invention relates to an optical transistor which uses photo-excited carriers to modulate the interaction between the plasma oscillation of free carriers and input electromagnetic radiation to change reflectivity by a large margin, thereby realizing high-speed light modulation, light switching and light detection. The device functions like a transistor, but uses a light beam instead of an electric current. The invention also provides implementation schemes for different devices using optical transistors such as a light power modulator, a combined detector, a reflective or transmissive light switch and a spectral scanner.

Abstract: A means, method and apparatus is disclosed for providing at least one phase-modulated output from at least one amplitude-modulated input, which is used to produced the logical AND and OR functions having phase modulated outputs. A constant level bias beam set of at least one wavelength of any wave-type energy is superimposed on at least one modulated input beam set having an energy sum out of phase with the bias beam set at at least one location. Energy in the resulting interference image is separated from said at least one location to produce at least one output. Input levels determine the function performed. When the input energy sum is greater than the bias beam set, the output changes phase. When they are equal, the output is zero, which is also used to produce the NAND function.

Abstract: An optical code recognition unit (OCRU) for recognising a predetermined n-bit optical code sequence coded using the Manchester code format, has an n-way splitter (7) having an input and n parallel outputs (7a). A plurality of gates (9a, 9b, 9c, 9d) are associated with the splitter outputs (7a), respective pairs of splitter outputs leading to each of the gates ( 9a, 9b, 9c) via a respective optical combiner (8a, 8b, 8c), and any remaining single splitter output leading directly to its gate (9d). Each of the splitter outputs (7a) is subject to a different delay of m half bit periods, where m=0 to 2(n-1), the values of m being chosen such that, if a predetermined optical code sequence is applied to the splitter input, the `1`s in the outputs of each of the pairs of splitter outputs (7a) reach the associated AND gates (9a, 9b, 9c) and the `1` in any remaining single splitter output (7a) reaches its AND gate (9d) at predetermined times such that all the gates are turned on.

Abstract: Operation results for all combinations of input optical signal values to be operated are previously determined and substantially parallel light beams reflecting the operation results for all combinations are generated. Selectors for selecting transmission area of the input light beams in accordance with digital information born by optical signals are arranged for the respective optical signals along the direction of propagation of the light beams. Through the logically cascade-connected selectors, an optical signal corresponding to a combination of current input optical signals is selected from the operation results for all combinations.

Abstract: Optical logic gates are designed using inverse-scattering theory, resulting in devices which are intrinsic and passive, having high extinction ratios and large fan out. The Boolean operation is modeled by a pair of reflection coefficients, corresponding to the `1` and `0` states of the device. When inverse scattering theory is applied, each reflection coefficient yields a unique refractive index profile. The multivalued nature of the refractive index profile is achieved by introducing nonlinearity in the core region of a thin-film waveguide, which acts as the basic structure of the devices.

Abstract: An optical information processor for use as a matrix vector multiplier comprises a vector input spatial light modulator (1) and an optically addressed weight matrix spatial light modulator (3). A read beam (10) passes through the input modulator (1) and the weight modulator and onto a combined output transducer and error spatial light modulator (5). The error modulator (5) is then controlled in accordance with the difference between a target output vector and the output vector from the transducer (5), and modulates an update beam (11) which then passes through the input modulator (1) and onto the weight modulator (3). The weight modulator (3) represents a two-dimensional array of optical attenuation values which are updated in accordance with the optical radiation incident thereon during updating.

Abstract: Optical communication systems, optical computing systems and optical logic elements which rely on the phenomina of cross-phase modulation to alter and control, either or simultaneously, the spectral, temporal or/and spatial properties of ultrashort light pulses for processing information with high speed repetition rates. A weak beam of ultrashort light pulses is modulated by an intense beam of ultrashort light pulses by copropagating both beams through a non-linear medium such that cross-phase modulation effects are realized.

Abstract: Amplification and synchronization of photon pulses in optical computing chips is accomplished by placing parametric amplifying devices at predetermined spatial locations in the light conductive paths that make up the optical circuits in the chip. The laser pumping signal for the parametric amplifiers is clocked by a system clock which also clocks the generation of the data photon pulses in the optical circuits. By synchronizing the arrival of a pumping pulse with the arrival of the photon pulse at a parametric amplifier, the data pulse can be amplified, reshaped and resynchronized. The pumping pulse can be directed to the spatially located parametric amplifiers on the chip in a number of different ways. The chip could be masked except for the parametric amplifiers, and the entire chip could be illuminated by the pumping laser though collimating lens. If the chip is not masked, then pumping light must be directed only to the parametric amplifiers.

Abstract: An optical interconnect network has four stages (S.sub.4 to S.sub.7) each formed from two-dimensional perfect shuffle interconnect stage (6) and a two-dimensional array of processing modules (8) each of which has a two-dimensional array of inputs and outputs. The use of two-dimensional modules provides an increase in optical channels which can be processed compared to the equivalent one-dimensional modules. The modules can perform switching functions.

Abstract: An optical logic operation apparatus includes an optical induction refractive index crystal having first and second planes parallel to each other and a device for inputting a coherent probe light from the first plane of the crystal. At least one of the first light output from the first plane of the crystal and the second light output from the second plane of the crystal is taken out so that one of the first and second lights is amplified by the two-wave coupling of the probe light reflected by the second plane and the probe light inputted from the first plane and the other light is attenuated likewise by the two-wave coupling. The inputted image is projected onto the crystal by use of light incoherent to the probe light. With the incidence of the incoherent light, a gain distribution corresponding to the inputted image is generated in the crystal so as to modulate the first and second lights spatially.

Abstract: Timing restoration for a series of input pulses is performed optically in a transmission or switching system, using a nonlinear material with negligible walk-off that also receives an essentially orthogonally polarized series of reference pulses. In the nonlinear material, the input pulses are frequency shifted by the presence of the reference pulses. For a material with negligible walk-off, the frequency shift only occurs when the pulses partially overlap, but not when the pulses are coincident. The frequency shifted output from the nonlinear material is supplied to a dispersive delay line that translates the frequency shift into a time shift, such that the input pulses are retimed by the reference pulses. If the nonlinear material has a nonlinear index of refraction n.sub.2 >0, then the dispersive delay line must have an anomalous Group Velocity Dispersion (GVD); on the other hand, if the nonlinear material has an index of refraction n.sub.2 <0, then the dispersive delay line must have a normal GVD.

Abstract: An optical system includes a first light emitting device for emitting a first polarized light beam other than a linearly polarized light beam, and a second light emitting device for emitting a second polarized light beam other than the linearly polarized light beam. The second polarized light beam has a pulse waveform. The optical system also includes a semiconductor device receiving the first and second polarized light beams. The semiconductor device has heavy holes and light holes. Each of the first and second polarized light beams has a wavelength which excites either heavy holes or light holes so that electrons are generated. The second polarized light beam is projected onto the semiconductor device in a state where the first polarized light beam is being projected onto the semiconductor device.

Abstract: An integrated optical device consisting of a monolithic crystalline substrate, an optical waveguide channel having an input end-face and an output end-face formed on the substrate and extending longitudinally along the substrate, the optical waveguide channel having at least one optical gate consisting of a non-linear organic polymer, a signal input path to the optical gate, and an interface for controlling the state of each optical gate.

Abstract: An optical system for auto-associative and hetero-associative recall utilizing Hamming distance as the similarity measure between a binary input image vector V.sup.(k) and a binary image vector V.sup.(m) in a first memory array using an optical Exclusive-OR gate for multiplication of each of a plurality of different binary image vectors in memory by the input image vector. After integrating the light of each product V.sup.(k) .times.V.sup.(m), a shortest Hamming distance detection electronics module determines which product has the lowest light intensity and emits a signal that activates a light emitting diode to illuminate a corresponding image vector in a second memory array for display. That corresponding image vector is identical to the memory image vector V.sup.(m) in the first memory array for auto-associative recall or related to it, such as by name, for hetero-associative recall.

Abstract: A light activated AND gate is disclosed which generates a light signal at a first output port in response to the simultaneous presence of light signals at an input port and a control port. With a light signal present at the control port, a light beam at the input port is reflected from an interface between two regions having different indices of refraction, and the reflected light beam then exits through a first output port. In the absence of a light signal at the control port, the two regions of the switching device have the same index of refraction, and the light beam at the input port passes through both regions and exits through a second output port.

Abstract: A fundamental method and apparatus for using wave-type energy, such as light, to provide: amplification, energy control, and logic functions including OR, EXCLUSIVE OR, and INVERTER; as well as: bistable information storage; computing; visual display; and dynamic imaging (where images are modified continually as computation proceeds) is disclosed. The method uses modulated input beams that are able to produce interference fringes, that are separated into constructive interference component regions and destructive interference component regions, to provide outputs from individual functions, that result from the interference which occurs in the separated interference-fringe component regions. Many basic functions are interconnected to produce more complex functions including complete digital and analog computers. Holograms made up of many subholograms are used to separate fringe component regions, and to direct function interconnecting beams.

Abstract: A multiple-faced optical device comprising a light-responsive element having multiple faces, at least two of the faces constituting input faces for receipt of non-collinear light signals and at least one of the faces other than the input faces constituting an output face from which light signals transmitted through the light-responsive element are emitted. The light-responsive element is further configured to have optically-induced non-linear susceptibility to light signals transversely propagated through the light-responsive element such that at least one portion of the light-responsive element switches between two stable optical states in dependence on the total intensity of the light signals within the light-responsive element. The above-described optical device can be configured to perform various operations, such as AND/OR and INVERT/PASS logic operations, data line branching, signal time delay, and memory storage.