Abstract: A system and method are disclosed for carrying additional information data on multiplexed signals which are modulated on different wavelengths. An information code such as an address or control data for a particular data signal at a selected wavelength is overlaid on the parallel multiplexed signals. The information code may be overlaid by attenuation or changing the amplitude of the different signals. A separate marker channel at a separate wavelength is also multiplexed with the data signals to indicate the presence of an information code. An optical data detector array is used to optically determine the encoded address by comparing the signals with light levels and producing an output when a matching code is detected. The optical data detector array uses a series of detectors each corresponding to the wavelength of light signals carrying the information data.

Abstract: An optical signal receiver for rapid and error free translation of optical signals into electrical signals is disclosed. The receiver is coupled to a light source. The light source is amplified and then split into two segments. One of the segments is delayed by a specific amount of time. Both segments are optically coupled to a photo detector. Each photo detector is coupled in parallel and are connected by two output terminals. When the voltage output by each photo detector is equal, the output terminals are balanced and will not have any voltage. The circuit will provide a voltage output on the terminal only on differential photocurrents sensed by the detector elements. The quiescent magnitude of the voltage output is a function of the value of the reverse bias voltage applied by the two voltage sources.

Abstract: A dual sensor detector incorporates a fire sensor, such as a smoke or heat sensor, and a gas sensor. Control circuitry is coupled to the sensors. In response to a sensed fire condition, such as due to heat or smoke, a constant sample rate sampling parameter, such as a sample time interval or a drive amplitude, is increased for the second sensor so as to increase its signal-to-noise ratio and resolution. The second sensor will be operated with the increased sample interval or drive amplitude so long as the first sensor continues to exhibit the detection of a condition. When the first sensor drops outs of the detection of a condition, the alterable parameter of the second sensor is reset to its quiescent state which draws a lower current value.

Abstract: An artificial retinal device, implanted in the subretinal space of the eye in persons with certain types of retinal blindness, induces artificial vision by electrical stimulation of the remaining viable cells of the retina. The artificial retina device includes a stimulating electrode unit preferably placed in the subretinal space, and a tail-like extension housing a distant electrical return ground electrode unit that may be placed in the vitreous cavity. The stimulating electrode unit includes an array of electrode subunits. Each electrode subunit includes one or more microphotodiodes electrically connected, for example, in series to provide increased voltage and current to its microelectrode. The stimulating electrode unit and the ground return electrode of the ground return electrode unit are preferably disposed on opposite sides of the neuroretina to allow for efficient and high resolution transretinal electrical stimulation of the neuroretinal cells.

Abstract: A multi-function detector has at least two different sensors coupled to a control circuit. In a normal operating mode the control circuit, which could include a programmed processor, processes outputs from both sensors to evaluate if a predetermined condition is present in the environment adjacent to the detector. In this mode the detector exhibits a predetermined sensitivity. In response to a failure of one of the sensors, the control circuit processes the output of the remaining operational sensor or sensors so that the detector will continue to evaluate the condition of the environment with substantially the same sensitivity.

Abstract: An optical operational amplifier is disclosed. The operational amplifier has a first photodiode with an anode and a cathode. A second photodiode with an anode coupled to the cathode of the first photodiode, and an anode coupled to the cathode of the first photodiode to form an output terminal. A resistor is coupled in parallel with the first and second photodiodes. The inputs to the operational amplifier are light sources which generate different currents in the first and second photodiodes. The output voltage from the output terminal is a function of the difference in currents across the first and second photodiode. The output voltage is amplified in proportion to the value of the resistor. The basic optical operational amplifier configuration may be used in a variety of useful circuits. One example is the use of the amplifier in a position sensing device which determines position of a light beam by the output of photodiode sensing elements.

Abstract: The present invention relates to a transmission method and device for efficient compression of digital data. The invention uses an optoelectronic coupler to receive light signals from a light transmitter at two bandwidths. A modulated signal generator is coupled to the transmitter which coverts voltage phase data signals to light signals. The data signals are modulated with a plurality of master profiles and subprofiles with different cycle time variations. The optoelectronic coupler has a pair of photodiodes. Light filters disposed on both diodes allow either the first or second bandwidth of light to pass. Conductors electrically couple the anode of the each photodiode to the cathode of the other photodiode which produce the voltage phase signal. A signal receiver is connected to the coupler and decodes the voltage-phase signal.

Abstract: An image processing system for capturing and compressing images into a digital format is disclosed. The system has an array of imaging pixel elements which consist of two photodiode detectors. One photodiode detector is a capture detector while the other detector is a reference detector. The capture detector has an anode electrically coupled to the cathode of the reference detector. The cathode of the capture detector is electrically coupled to the anode of the reference detector. An image may be compared to a reference image detected by the reference detector. Different levels of light between the captured image and the reference image change the electrical output of the opsistor. Image compression is facilitated since only pixel elements which change from frame to frame need be stored. Additionally, a processing and compression circuit may use column and row scans to eliminate unchanged pixels and store only pixels with different light levels between images.

Abstract: The present invention relates to a transmission method and device for efficient compression of digital data. The invention uses an optoelectronic coupler to receive light signals from a light transmitter at two bandwidths. A modulated signal generator is coupled to the transmitter which coverts voltage phase data signals to light signals. The data signals are modulated with a plurality of master profiles and subprofiles with different cycle time variations. The optoelectronic coupler has a pair of photodiodes. Light filters disposed on both diodes allow either the first or second bandwidth of light to pass. Conductors electrically couple the anode of the each photodiode to the cathode of the other photodiode which produce the voltage phase signal. A signal receiver is connected to the coupler and decodes the voltage-phase signal.

Abstract: An image processing system for capturing and compressing images into a digital format is disclosed. The system has an array of imaging pixel elements which consist of two photodiode detectors (Opsistor). One photodiode detector is a capture detector while the other detector is a reference detector. The capture detector has an anode electrically coupled to the cathode of the reference detector. The cathode of the capture detector is electrically coupled to the anode of the reference detector. An image may be compared to a reference image detected by the reference detector. Different levels of light between the captured image and the reference image change the electrical output of the opsistor. Image compression is facilitated since only pixel elements which change from frame to frame need be stored. Additionally, a processing and compression circuit may use column and row scans to eliminate unchanged pixels and store only pixels with different light levels between images.

Abstract: A wavelength-portion controllable optoelectronic switch ("Opsistor") capable of rapid switch frequencies fabricated as a monolithic integrated circuit is disclosed. The Opsistor is comprised of two inverse parallel photodiodes in close proximity, preferably on a monolithic silicon substrate, such that the anode of one photodiode is electrically connected via a first conductor to the cathode of the second photodiode, and the cathode of the first photodiode is electrically connected via a second conductor to the anode of the second photodiode. The voltage-phase of the Opsistor is determined by the relative illumination to the Opsistor's two photodiodes and is rapidly switchable. As a receiving device for data signals, the Opsistor receives programming signals from a transmitter light source.