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 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: 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 visible and infrared light powered retinal implant is disclosed that is implanted into the subretinal space for electrically inducing formed vision in the eye. The retinal implant includes a stacked microphotodetector arrangement having an image sensing pixel layer and a voltage and current gain adjustment layer for providing variable voltage and current gain to the implant so as to obtain better low light implant performance than the prior art, and to compensate for high retinal stimulation thresholds present in some retinal diseases.

Abstract: An artificial retina device and a method for stimulating and modulating its function is disclosed. The artificial retina device is comprised of plural multi-phasic microphotodiode subunits. In persons suffering from blindness due to outer retinal layer damage, a plurality of such devices, when surgically implanted into the subretinal space, may allow useful formed artificial vision to develop. One device, called a MMRI-4, transduces light into electric currents to stimulate the retina. The four microphotodiode subunits of the MMRI-4 are oriented so that each flattened sides of the MMRI-4 has two subunits in a PiN configuration and two subunits in a NiP configuration. The flattened cubic shape of the MMRI-4 will allow one or the other of the two flattened sides to be preferentially directed toward incident light when implanted in the subretinal space.

Abstract: A visible and infrared light powered retinal implant is disclosed that is implanted into the subretinal space for electrically inducing formed vision in the eye. The retinal implant includes a stacked microphotodetector arrangement having an image sensing pixel layer and a voltage and current gain adjustment layer for providing variable voltage and current gain to the implant so as to obtain better low light implant performance than the prior art, and to compensate for high retinal stimulation thresholds present in some retinal diseases.

Abstract: An artificial retina device and a method for stimulating and modulating its function is disclosed. The artificial retina device is comprised of plural multi-phasic microphotodiode subunits. In persons suffering from blindness due to outer retinal layer damage, a plurality of such devices, when surgically implanted into the subretinal space, may allow useful formed artificial vision to develop. One device, called a MMRI-4, transduces light into electric currents to stimulate the retina. The four microphotodiode subunits of the MMRI-4 are oriented so that each flattened sides of the MMRI-4 has two subunits in a PiN configuration and two subunits in a NiP configuration. Filter layers disposed on the PiN configuration will allow visible light to induce a PiN current, and filter layers disposed on the NiP configuration will allow infrared light to induce a NiP current.

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: An artificial retina device and a method for stimulating and modulating its function is disclosed. The artificial retina device is comprised of plural multi-phasic microphotodiode subunits. In persons suffering from blindness due to outer retinal layer damage, a plurality of such devices, when surgically implanted into the subretinal space, may allow useful formed artificial vision to develop. One device, called a MMRI-4, transduces light into electric currents to stimulate the retina. The four microphotodiode subunits of the MMRI-4 are oriented so that each flattened sides of the MMRI-4 has two subunits in a PiN configuration and two subunits in a NiP configuration. By projecting real or computer controlled visible light images, and computer controlled infrared light images or illumination, simultaneously or in rapid alternation onto the MMRI-4s, the nature of induced retinal images may be modulated and improved.

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.

Abstract: Microscopic photodiode devices with semi-transparent surface electrodes are combined with a liquid or other suitable vehicle. Together they are injected into the subretinal space of the eye. The purpose of these microphotodiode photovoltaic devices is to transduce incident light into electric current which stimulate the overlying cellular layers of the retina. In persons suffering from visual dysfunction due to outer retinal layer damage, such devices may allow useful formed artificial vision. These independent surface electrode microphotodiodes (ISEMCPs) may be in the shape of micro-spheres, micro-cylinders or other micro-shapes. An off-center embedded ferromagnetic layer will confer magnetic susceptibility to the ISEMCPs. A magnetic field applied in the vicinity of the eye will align the ISEMCPs within the subretinal space directing their photoactive surface toward incident light.

Abstract: Microscopic photoelectric devices with semitransparent surface electrodes are combined with a liquid or other suitable vehicle. Together they are injected into the subretinal space of the eye. The microscopic photoelectric devices transduce incident light into electric current that will stimulate the overlying cellular layers of the retina. In persons suffering from visual disfunction due to outer retinal layer damage, such devices may allow useful formed artificial vision. The preferred independent surface electrode microphotodiodes (ISEMCP's) may be in the shape of microspheres, microdiscs or other microshapes. The ISEMCP's are formed of either PiN or NiP type semiconductors, or a combination of both, in a single unit. These devices will form a dipole when exposed to light due to the electric current generated. A magnetic field applied in the vicinity of the eye may help align the ISEMCP's within the retina so that their photo-active surfaces face the incident light.

Abstract: A silicon chip device composed of a large array of densely packed microphotodiodes is implanted between the inner and outer retina layers, in patients with vision-deficient eyes suffering from retinal dysfunction, to allow for useful formed vision. The photoactive surface of each photodiode, with its silicon deposited or etched electrode, point towards the incident light. The device produces an amplitude-modulated current to stimulate the inner retinal layer. The device is intrinsically inert due to its doped silicon substrate nature.

Abstract: A silicon chip device composed of a large array of densely packed microphotodiodes is implanted between the inner and outer retina layers, in patients with vision-deficient eyes suffering from retinal dysfunction, to allow for useful formed vision. The photoactive surface of each photodiode, with its silicon deposited or etched electrode, point towards the incident light. The device produces an amplitude-modulated current to stimulate the inner retinal layer. The device is intrinsically inert due to its doped silicon substrate nature.