Abstract: An implantable atrial defibrillator delays therapy intervention for a delay time period after initial detection of fibrillation to provide the atria with an opportunity to spontaneously revert to normal sinus rhythm before cardioversion is attempted. A timer times the delay time period responsive to the first initial detection of fibrillation by a fibrillation detector. After timer time-out, the fibrillation detector redetects for atrial fibrillation. If the atria are still in fibrillation, a cardiovertor cardioverts the atria. If the atria are not in fibrillation, cardioverting therapy is withheld.

Abstract: A cardiac monitor which is fully implantable beneath the skin of a patient monitors heart rate variability of a human heart. The heart rate monitor includes at least one electrode which establishes electrical contact with the heart. During a heart monitoring period, time intervals between adjacent heart beats are determined for generating heart rate data. The heart rate data is stored in a memory which is accessed after the completion of the heart monitoring period for generating a heart rate variability factor. The heart rate variability factor is stored in memory for later transmission to a nonimplanted external receiver.

Abstract: A catheter insertable into a body provides for both sensing electrical activity of the heart at localized locations of the heart and defibrillating the heart when defibrillation is required. The catheter includes a plurality of connectors at the proximal end and a plurality of electrodes disposed along the catheter at the distal end. The plurality of electrodes includes a first plurality of electrodes and a second plurality of electrodes. The first plurality of electrodes are coupled together and to a given one of the plurality of connectors. Each of the second plurality of electrodes is coupled to a respective different one of the plurality of connectors. The first plurality of electrodes provide for defibrillating the heart and the second plurality of electrodes provide for sensing electrical activity of the heart at localized locations of the heart.

Abstract: An implantable atrial defibrillator provides a pulse of defibrillating electrical energy to the atria of the heart in synchronism with sensed R waves in response to non-coincident sensing of an R wave at first and second areas of the heart. The defibrillating pulse is provided after a predetermined number of consecutive R waves are non-coincidently sensed to assure reliable synchronization. The atrial defibrillator is also operational in a marker mode wherein a number of synchronization marker pulses are delivered to the heart for detection on an externally generated electrocardiogram. The atrial fibrillation detector of the defibrillator is normally disabled and is activated when the sensed ventricular activity indicates a probability of atrial fibrillation to conserve a depletable power source. An endocardial lead is also described which ensures that the delivered atrial defibrillating electrical energy is substantially confined to the atria of the heart.

Abstract: A post-surgical cardioverting system and method applies cardioverting electrical energy to the atria of the heart of a post-surgical heart patient. The system includes a first lead including a first elongated electrode having a proximal end and a distal end, a second lead including a second elongated electrode having a proximal end and a distal end, and sutures for releasably anchoring the distal ends of the first and second electrodes to the pericardium and disposing the first and second electrodes along the pericardium overlying the right and left atria respectively. A non-implantable cardiovertor is coupled to the first and second leads for applying the cardioverting electrical energy to the first and second electrodes. When cardioversion is no longer required, the first and second leads may be pulled out of the patient's chest.

Abstract: An implantable atrial defibrillator cardioverts the atria of a patient's heart and determines the quantity of cardioverting electrical energy required for cardioverting the atria of the patient. The atrial defibrillator includes a detector for detecting atrial activity of the heart and an atrial fibrillation detector for determining when the atria of the heart are in fibrillation. A delivery stage is selectively operable in a test mode for applying fibrillation inducing electrical energy to the atria when the atria are not in fibrillation for inducing fibrillation. When fibrillation is induced, the delivery stage repeatedly applies test cardioversion electrical energy to the atria until the atria are cardioverted. Thereafter, a value indicative of the quantity of the test cardioversion energy last applied to the atria is stored for future reference when the atrial defibrillator is in a normal operating mode.

Abstract: An implantable cardiac monitor is arranged for detecting both arrhythmias and ischemia of the human heart. The monitor includes subcutaneous electrodes for establishing electrical contact with the heart and a sense amplifier coupled to each electrode for generating an electrocardiogram of a heart beat sensed at each of the electrodes. The electrocardiograms are digitized and the digital samples thereof are stored in a memory. A microprocessor processes the digital samples of the electrocardiograms and generates characterizing data indicative of the physiology of the heart. The cardiac monitor includes telemetry to permit the cardiac data to be interrogated externally of the patient for obtaining the generated cardiac data indicative of arrhythmic and ischemic episodes.

Abstract: An intravenous lead for use with a cardiac device implantable beneath the skin of a patient provides positive fixation for the lead when implanted in an artery or vein of the heart. The lead includes a lead body adapted to be fed into an artery or a vein of the heart of a patient and at least one electrode carried by the lead body and adapted to be coupled to the implantable cardiac device. The lead body includes a preformed section having a resiliently coiled configuration. The coiled section makes substantially continuous surface contact with inner wall surfaces of the artery or vein after the lead is implanted within the artery or vein for providing positive fixation of the lead.

Abstract: An apparatus treats a stiffened joint of at least one finger of the hand and includes a first member for engaging the metacarpal phalangeal joint of the finger and a second member movable with respect to the first member for engaging a surface of the finger on the side of the stiffened joint opposite the metacarpal phalangeal joint. The apparatus further includes at least one threaded member for exerting pressure against the second member for bending the stiffened joint and retaining the apparatus on the hand.

Abstract: There is disclosed a device to be worn by a human patient for maintaining the upper airway passage of the patient in an open, unobstructed position. The device includes a lower portion arranged to rest upon the upper thorax of the patient and an upper portion connected to and braced by the lower portion. The upper portion includes means for lifting the lower jaw of the patient and thrusting the lower jaw of the patient forward. A posterior portion connected to the lower and upper portions maintains the positioning of the lower and upper portions and prevents backward movement of the patient's lower jaw.

Abstract: A solid state semiconductor device is disclosed which is programmable so as to alter the impedance between its two terminals. In many embodiments, the device is programmable to have any one of four conditions: a first in which the electrical impedance is relatively high in both directions; a second in which the impedance is relatively high in one direction and relatively low in the opposite direction; a third in which the impedance is relatively high in the opposite direction and relatively low in the first direction; and a fourth in which the impedance is relatively low in both directions. Such a programmable device can be made with semiconductor layers which form two series coupled back-to-back diodes, each of which can be selectively programmed to lose its rectifying feature. Structures are disclosed which include a plurality of such programmable devices in one or more separately programmable planes, each with its own addressing means.

Abstract: A new and improved thin film field effect transistor and method provides such a transistor having increased operating frequencies and higher output currents. The transistor includes a gate electrode having a non-coplanar surface with respect to the substrate and a deposited semiconductor material overlying the gate electrode to form a current conductor channel between a source and drain. The length of the current conduction channel is determined by the thickness of the gate electrode which can be accurately controlled. As a result, short channel lengths are possible without high precision photolithography for high output currents and fast operating speeds. Further, a gate insulator is disposed between the gate and the deposited semiconductor. The gate insulator, which can be a gate oxide, can be annealed prior to the deposition of the deposited semiconductor to provide enhanced field effect mobilities. This further increases the transistor output currents and operating speeds.

Abstract: Disclosed is a device and method for the storage and conversion of a light input into a corresponding output with light from another source. The device includes an improved liquid crystal light valve having as a photosensor layer a deposited memory semiconductor material which is reversibily convertible between a first stable, relatively high electrical resistance condition and a second stable, relatively low electrical resistance condition. Each change of state or condition will remain after cessation of the input until stimulated to reverse to the other state, thereby achieving a storage or memory function.

Abstract: A high performance, small area thin film transistor has a drain region, an insulating layer, and a source region at least portions of the edge of which form a non-coplanar surface with respect to a substrate. The insulative layer is formed in between the source and drain regions. A deposited semiconductor overlies the non-coplanar surface to form a current conduction channel between the drain and source. A gate insulator and gate electrode overly at least a portion of the deposited semiconductor adjacent thereto. The length of the current conduction channel is determined by the thickness of the insulative layer and therefore can be made short without precision photolithography. The non-coplanar surface can be formed by utilizing a dry process to simultaneously etch through several layers in a continuous one-step process. A second dielectric layer may be formed above the three previous layers.

Abstract: A system is disclosed which includes a transmissive liquid crystal display of the type which may display a line of characters or symbols at a time, or which may display only a raster line in combination with an energy source and a controllable and transportable medium. The medium is exposed by energy from the source of energy passing through the liquid crystal display which acts as a mask for the source of energy. The liquid crystal display may be set by electrical signals manually generated such as by a keyboard or by signals automatically generated by use of other electronic equipment. In one alternate embodiment of the invention a large area two-dimensional liquid crystal display is used as a mask. In another embodiment of the invention a liquid crystal display is used as a mask for the purpose of exposing a photoconductive drum of the type used in xerography. A reflective liquid crystal display is disclosed in yet another embodiment of the invention.

Abstract: A method of making a parallel programmed electronic matrix array including the steps of forming at least one layer of a phase changeable material on a conductive substrate, wherein the phase changeable material has a substantially nonconductive state and a comparatively high conductive state. The layer is formed in one of the states. The method also includes irradiating selected areas of the layer to simultaneously convert the selected areas of the layer to the other one of the states to form selected substantially nonconductive layer portions and selected comparatively high conductive layer portions. Thereafter, in a preprogrammed embodiment, first and second sets of electrically conductive address lines are formed on respective opposite sides of the layer.

Abstract: A device and method for converting an X-ray image into a corresponding output image with light from a different source and a phosphorescent layer in conjunction with a liquid crystal light valve. The light valve includes a photosensor layer comprised of a deposited semiconductor material having distinct light and dark photoconductivities, the light photoconductivity being substantially greater than the dark photoconductivity.When impinged upon by an particular pattern of X-rays, the phosphorescent layer phosphoresces in a corresponding pattern, which phosphorescence in turn causes the semiconductor layer to be switched to its light photoconductivity in a pattern also corresponding to that of the input X-ray image. The pattern of switched semiconductor in the photosensor layer allows a biasing voltage to be switched over to the liquid crystal layer of the light valve in a corresponding pattern.

Abstract: Light influencing subassemblies and displays each having a structure in which all of the pixel electronic circuitry, including isolation devices where utilized, are located at one electrode side of each pixel electrode combination. The structure includes the subdivision of one pixel electrode into at least two spaced apart side-by-side electrode segments opposite a common electrode. The displays include light influencing material disposed between the segmented and common electrodes. The electrode segments further can include at least one isolation device coupled to at least one of the segments which facilitates selective excitation of the pixel elements and applied potential reversal across the electrodes during alternate display frames. The displays have an increased manufacturing yield, reduced capacitance and increased isolation. Also disclosed is a method of making the subassemblies and displays.

Abstract: A high speed digital electronic system includes a plurality of logic or switching circuits for providing one or more bits of discrete output in response to applied input signals. At least some of the circuits include devices switchable between at least two logic states, and are formed from materials of the type which exhibit increased switching speeds when maintained in a dynamic mode of operation. Signal source means apply to the system dynamic signals for maintaining the switchable devices in a dynamic mode of operation. The switchable devices are preferably formed from amorphous semiconductor alloys including silicon and may take the form of diodes to form AC logic AND gates, OR gates or a matrix selection circuit. The dynamic signals take the form of alternating major and minor clock pulses having a frequency between 10 and 40 megahertz. The logic circuits are arranged to form a binary adder.

Abstract: There is disclosed a new and improved material and device for improved selective absorption of light energy for use in photothermal applications and a method and apparatus for manufacturing same.The device includes a layer of thermal infrared radiation reflecting material containing a transition metal or stainless steel. A solar radiation absorbing layer is deposited over the infrared reflecting layer. This layer comprises either amorphous boron or an amorphous alloy of boron and silicon, boron and germanium or boron and molybdenum.Finally, a solar radiation antireflecting material layer is deposited over the solar radiation absorbing layer. This layer comprises an amorphous alloy of nitrogen and either silicon or boron.