Abstract: A personal storage device for receipt, storage, and transfer of digital information to other electronic devices has a pocket sized crush resistant casing with a volume of less than about ten cubic centimeters. A processor is positioned within the casing cavity and attached to the crush resistant casing, while a memory module also positioned within the casing cavity is configured to store received executable applications and data. An infrared transceiver is mounted on the crush resistant casing and in electronic communication with the processor and memory module to provide for receipt and storage of executable applications, and receipt, storage, and transfer of digital information to other electronic devices. The digital information stored by the personal storage device can be intermittently synchronized with other electronic devices.

Abstract: An optical-signal/electric-signal converting device communications system for a communications system that establishes communications using electric and optical signals. The converting device converts an electric transmission signal into an optical transmission signal and an optical transmission signal into an electric transmission signal. The converting device includes an electric signal receiving circuit for receiving the electric transmission signal transmitted from the host computer of the communications system through an electric transmission line, and a modulating circuit for modulating the electric signal sent from the electric signal receiving circuit into a pulse signal having pulses of a smaller width.

Abstract: An optical time shifter and routing system having high efficiency switched gratings to form optical time delay and routing networks. This system also includes a unique passive noise suppression device that can be used in multiple channel optical systems such as time shifters and routers to increase channel isolation and reduce crosstalk. The latter noise suppression devices are applicable broadly to the free-space time shifters as well as to other time shifters.

Abstract: A multiple channel fiber optic multiplexer, demultiplexer, multiplexer/demultiplexer, and/or add/drop component includes a plurality of Mach-Zehnder interferometer units, each unit including a pair of 50/50 fiber optic couplers connected by a pair of Bragg gratings and three functional ports including two multi-channel input output ports, one single channel input/output port, the Bragg gratings being tuned to a wavelength of the single channel input/output port, and input/output ports of adjacent interferometer units being connected to each other by fusion splices in a cascade configuration, the component including a first common input/output connector on a first of said cascaded interferometer units and a second common input/output connector on a last of said cascaded interferometer units, with the second common input/output connector being arranged to permit the addition of add-on multi-channel components.

Abstract: A light emitting control apparatus comprises a light emitting element which emits a light when an input electrical signal is converted into a light signal, a monitoring circuit which monitors the output level of the light emitting element, a sample-and-hold circuit which detects a peak value and is put into the sample mode when data of the monitoring circuit is in the mark state showing voltage and which is in turn put into the hold mode when the data is in the space state showing no voltage, and an amplifier which accomplishes negative feedback control of the output level of the light emitting element by using the output of the sample-and-hold circuit. Thus, the apparatus can quickly respond to a change of the input state and stabilize the output level of the light emitting element for a long time.

Abstract: A remote-controlled PC body (mainframe) and monitor controlling circuit includes a remote controller for generating an optical remote control signal in according to a key input; an optical reception unit for converting the optical remote control signal output the remote controller into an electrical remote control signal; and a first microcomputer for controlling the PC body when the electrical remote control signal output the optical reception unit is a PC body control signal to control a sound output circuit and motion picture output circuit in the PC body and for controlling the monitor when an electrical remote control signal output the optical reception unit is a monitor control signal, to control Display Power Management System and On screen display functions.

Abstract: A portable directional multi-channel receiver comprises a non-visual communicator, a self-contained source of electrical energy, a detector for receiving an amplitude modulated lightwave signal with at least two different frequency modulated subcarrier frequencies, and electronics converting the received signals into intelligible non-visual communication emanating from the communicator both in the presence and in the absence of an ambient background of light energy, such as sunlight. The device is adapted for use by the visually impaired, as well as those who are not fluent in the relevant printed language, in finding desired locations from which suitable modulated infrared signals are emitted.

Abstract: An optical fiber amplifier is free from optical oscillation, if operated for high output power level and can be manufactured at low cost. It comprises an input optical fiber 11 for receiving signal light, a first isolator 12 for blocking any return light of the optical signal entered into the input optical fiber 11, an erbium-doped optical fiber 13 for amplifying the entered optical signal, a pumping source 14, a wavelength division multiplexer 15 for coupling the signal light and the excited light from the pumping source 14, an optical signal output optical fiber 16 connected to the wavelength division multiplexer 15 to produce an amplified optical signal, a second isolator 17 arranged on the optical signal output optical fiber 16 and a excited light input optical fiber 19 for connecting the wavelength division multiplexer 15 and the pumping source 14 and the wavelength division multiplexer 15 has a dielectric multilayer filter 18 that reflects signal light and transmits excited light.

Abstract: An improved monitoring system for monitoring a fiber optic transmission system using optical side tones. The monitoring system includes a line monitoring equipment (LME) connected to a portion of an optical transmission system. The LME includes a pseudo-random sequence (PRS) tone generator for generating a PRS tone, a laser transmitter for transmitting an LME optical side tone based on the PRS tone. The LME includes a delay system for delaying the PRS tones, an optical filter for passing only the wavelength of the LME side tone. A plurality of data channels are transmitted over the system using WDM. A coupler is used to combine the WDM data with the LME side tone. A repeater having an optical loopback coupler returns a portion of the combined signal to the LME. The comparator/correlator correlates the delayed PRS tones with the LME side tone returned by each repeater.

Abstract: An infrared (IR) communication system is described in which a base unit for a cell can communicate with a plurality of infrared portable devices through distributed infrared receiver/transmitter (RT) modules over a plurality of channels using IR carrier signals. A call or signal processor, referred to as a radio exchange unit, and controlling communication of a cell, communicates with the base unit to place or receive calls with the IR portable devices. The communication occurs in standard communication frames divided into transmission and receiving segments with each segment further divided into slots and with the slots containing digital data, with each communication-channel formed by a slot. Each transmission segment to an RT module is immediately followed by a responsive receiving segment.

Abstract: An optical communications device is disclosed which is equipped with a transmission unit adapted to send binary-coded electrical pulse signals to another optical communications device in the form of optical pulse signals. The transmission unit includes a modulator for producing an electrical pulse signal of a narrow pulse width only at each of rising and falling edges in the binary-coded electrical pulse signals and an electro-optic converter for converting the electrical pulse signal of a narrow pulse width into an optical pulse signal of a narrow pulse signal. As an alternative, the transmission unit includes a modulator which produces an electrical pulse signal of a narrow pulse width for each bit in the binary-coded electrical pulse signals only when it is at a high level and an electro-optic converter which converts the electrical pulse signal of a narrow pulse width into an optical pulse signal of a narrow pulse width.

Abstract: A digital optical receiver and clock recovery circuit for use in detecting and retiming optical data transmitted at rates up to and exceeding 40 Gb/s. The receiver is made, in part, of superconducting Josephson junctions. The receiver includes an optical signal detector, an SFQ (single flux quantum) transition detector for converting the signal from the photodetector into a stream of single flux quantum signals, and a clock recovery circuit. The clock recovery circuit includes a superconducting ring oscillator in which an SFQ pulse rotates and provides a clock signal at an output of the oscillator. When a pulse from the stream of single flux quantum pulses arrives from the transition detector, two pulses are generated in the ring oscillator. One of the pulses eliminates the rotating SFQ pulse and the second pulse replaces the rotating SFQ pulse, thereby recovering the phase of the clock signal in one bit.

Abstract: An optical wavelength-division multiplexed bidirectional data link (FIG. 1) is constructed using a single multi-mode fiber (130). The link comprises the optical fiber with a single-lens optical transceiver (100, 150) at each end of the fiber. Each single-lens optical transceiver comprises a transmitter in the form of a surface-emitting light-emitting diode (LED 101) that emits light at a wavelength of 0.85 .mu.m, and a receiver in the form of a large-scale optical detector (102) and a dielectric optical filter (103) that has a passband at a wavelength of 1.3 .mu.m. In the other transceiver, the wavelengths of the transmitter and the receiver are reversed. The transceiver is made as a single integrated-circuit device and is coupled to the fiber by a single-lens optical coupler (110, 160).

Abstract: A system that uses all optical elements for transmission, regeneration and reception of solitons in point-to-point, broadcast, ring and multi-user trunk type communication systems. Soliton pulses from an optical clock source are modulated by optical data pulses in an optical modulator producing a modulated channel of data pulses. Several channels are combined by an optical multiplexer into a network optical bit stream. This stream is carried by an optical fiber and one or more of optical regenerators which recover the system clock and regenerate the signal with the recovered system clock rather than just amplifying the signal. Each of the regenerators can, in addition to regenerating the data, act as part of a data drop or insert node in a ring network where the node can synchronously remove data from or insert data into the stream. Intermediate nodes can include packet drop/replace nodes if the network is a packet type network.

Abstract: An analog lightwave communication system comprises at least two optical transmitters for providing optical information signals at different optical wavelengths. A dense wavelength division multiplexer includes at least two inputs for receiving the optical information signals from the optical transmitters and multiplexes the optical information signals to a composite optical signal at an output. Each input of the dense wavelength division multiplexer comprises at least one optical resonant cavity comprising first and second reflecting materials spaced to permit resonance at a selected wavelength. A fiber optic transmission system coupled to the output of the dense wavelength division multiplexer receives the composite optical signal.

Abstract: A switching network that utilizes at least three degrees of freedom, time, wavelength and space. In one embodiment that involves point-to-point switching, each space channel between an input and an output is assigned a time slot and wavelength coordinate characteristic of the output and the input transmitter and output receiver are tuned to the appropriate time and wavelength coordinates and selective switching is used to complete the space channel between the input and output. In another embodiment for generalized switching, each input channel is assigned a set of space, time slot and wavelength coordinates and an input signal is broadcast to all of the outputs which selectively makes connection to those inputs with an appropriate set of coordinates.

Abstract: The present invention relates to an arrangement for a multiple light path, which may be used for a wireless optical audio and/or video communication system.Known systems use a direct wireless infrared connection. It has been found that such a connection is not reliable enough. It is the object of this invention to realise a reliable infrared connection between different devices. This is realised by a two path connection. A first path is realised by a wireless connection and a second path is realised by a transmission at least partially through an optical fiber. Furthermore this invention presents a special lens and a special photo light emitting diode for the realisation of the two path infrared connection.The invention can used e.g. for the connection between a television set and a video cassette recorder.

Abstract: In order to provide an optical transmitter applicable for a transmission speed range higher than 1 Gb/s without transmission quality degradation, the embodiment of the invention comprises a flipflop having a set terminal supplied with a transmission signal and a variable delay circuit for delaying an inverse output of the flipflop to be supplied to a reset terminal of the flipflop, for equalizing pulse width of the laser light with that of the transmission signal.

Abstract: A wavelength demultiplexer having at least two photodetectors is disclosed. The photodetectors are arranged in sequential layers along an optical path. The photodetectors differ in bandgap, and are arranged so that the optical signal passes through relatively larger bandgap photodetectors before being received by relatively smaller bandgap detectors. Each photodetector absorbs photons within a predetermined energy range and generates a voltage as a function of the absorbed energy. The photodetectors can be used to detect, and hence demultiplex, a wavelength-division-multiplexed signal.

Abstract: An optical method for separating and routing local and express channel data comprises interconnecting the nodes in a network with fiber optic cables. A single fiber optic cable carries both express channel traffic and local channel traffic, e.g., in a massively parallel processor (MPP) network. Express channel traffic is placed on, or filtered from, the fiber optic cable at a light frequency or a color different from that of the local channel traffic. The express channel traffic is thus placed on a light carrier that skips over the local intermediate nodes one-by-one by reflecting off of selective mirrors placed at each local node. The local-channel-traffic light carriers pass through the selective mirrors and are not reflected. A single fiber optic cable can thus be threaded throughout a three-dimensional matrix of nodes with the x,y,z directions of propagation encoded by the color of the respective light carriers for both local and express channel traffic.