Abstract: A three-dimensional optical interconnection is disclosed having a stack of vertically aligned optoelectronic integrated (OEIC) modules. Each OEIC module includes an array of vertical cavity surface emitting lasers (VCSEL), receivers and electronic logic which are monolithically integrated on a single semiconductor substrate. Communication between the OEIC modules is effectuated by the free space propagation of laser radiation from the VCSELs to corresponding receivers on an adjacent OEIC module. Transistors, such as heterojunction bipolar transistors, may be used to drive the VCSELS.

Abstract: A signal transmission circuit having a latch-up function has a first and a second photo-couplers, each of which has a photo-diode (light emitting diode) and a photo-transistor. The photo-diode in the first photo-coupler is series-connected with the photo-transistor in the second photo-coupler between high and low voltage supplies. The other photo-diode and photo-transistor in said first and second photo-couplers are connected in the same way. As a result, signals are transmitted between those two photo-couplers with a high noise resistance.

Abstract: A reconfigurable digital optical lookup table for solving Boolean equations sing an array of bistable optical devices is provided. A single light source is divided into a matrix of light beams using binary phase gratings and a lens system. This matrix of beams is modulated by a spatial light modulator symmetric self electro-optic effect device (S-SEED) according to the desired lookup table. The modulated light beams are used to set an S-SEED array with the lookup table. The rows and columns of the S-SEED array are then reset according to the inputs to the Boolean equation. Once all of the inputs have been processed, the S-SEED array will have only one member whose state has not been affected by the inputs, and the value of this S-SEED corresponds to the solution to the Boolean equation. The final result is output by using a matrix of equal intensity light beams and a mask to read out the state of one side of the S-SEEDs, and focusing the result onto a detector.

Abstract: There is disclosed a photo-electronic integrated circuit device comprising a first and second output terminals for supplying first and second output signal of opposite polarities to an external differential input logic circuit, a photo-detecting device for converting an input light signal to an electrical signal, a first amplifier for amplifying the electrical signal of the photo-detecting device and outputting the same from the first output terminal as the first output signal, and a second amplifier for amplifying the output of the first amplifier and outputting the second output signal having the opposite phase to that of the first output signal, from the second output terminal.

Abstract: A structure providing a monolithic integration of an optical detector with an optical transmitter working in the region of the visible or the near IR spectrum. This source type makes it possible to transpose a perceived image belonging to a wavelength region to another wavelength region with a good output (photons/electrons coupling). Such a device may find particular application in imagery and signal processing systems.

Abstract: Monolithic optically bistable modulator arrays, such as an M.times.N array of S-SEEDs, are electrically addressed with a matrix of electrical row and column contacts. Connected to the center node of each S-SEED is an addressing means having elements, such as diodes, transistors, or capacitors, which are electrically enabled and disabled.

Abstract: A neural plane, which can form the basis of a neural network or a component thereof, is comprised by an optical modulator, an electrical non-linearity circuit and an optical detector interconnected whereby in use the non-linearity circuit controls the modulator in dependence on the detector output. There are parallel arrays (10, 11, 12) of such modulators, non-linearity circuits and detectors (M, T, D, 30, 33, 34). The modulator, non-linearity circuits and detectors have components formed in a common semiconductor substrate (20), for example by VLSI techniques with a silicon substrate, the modulators (30) may be comprised by liquid crystal on silicon in that case (FIGS. 4, 7).

Abstract: An integrated, optoelectronic, variable thresholding neuron implemented monolithically in a GaAs integrated circuit and exhibiting high differential optical gain and low power consumption. Two alternative embodiments each comprise an LED monolithically integrated with a detector and two transistors. One of the transistors is responsive to a bias voltage applied to its gate for varying the threshold of the neuron. One embodiment is implemented as an LED monolithically integrated with a double heterojunction bipolar phototransistor (detector) and two metal semiconductor field-effect transistors (MESFET's) on a single GaAs substrate and another embodiment is implemented as an LED monolithically integrated with three MESFET's (one of which is an optical FET detector) on a single GaAs substrate. The first noted embodiment exhibits a differential optical gain of 6 and an optical switching energy of 10 pJ. The second embodiment has a differential optical gain of 80 and an optical switching energy or 38 pJ.

Abstract: An optically functional device has a semiconductor substrate, a light receiving portion disposed on the semiconductor substrate for receiving input light, a light emitting portion disposed on the light receiving portion for emitting output light, a window disposed above the light emitting portion, through which input light and output light pass and a resistance layer made of a semiconductor for functioning as load resistance. The resistance layer is disposed at least in either place between the semiconductor substrate and the light receiving portion, or between the light receiving portion and the light emitting portion, or on the light emitting portion. The light emitting portion has a light emitting layer made of semiconductor material having an energy of forbidden band width of more than the energy of a main peak of input light.

Abstract: An optical switch in which states are defined by dynamic charge storage, rather than contention resolution, and which switches using pulsed radiation having a wavelength somewhat longer than the exciton wavelength in a SEED diode. The switch does not exhibit or need bistability but switches at a relatively low energy as compared to S-SEEDS switched at the exciton wavelength.