Abstract: A computer module is disclosed in which a stack of glued together IC memory chips is structurally integrated with a microprocessor chip. The memory provided by the stack is dedicated to the microprocessor chip. The microprocessor and its memory stack may be connected either by glue and/or by solder bumps. The solder bumps can perform three functions--electrical interconnection, mechanical connection, and heat transfer. The electrical connections in some versions are provided by wire bonding.

Abstract: A method for fabricating stacks of IC chips into modules providing high density electronics. A relatively large number of layers are stacked, and then integrated by curing adhesive applied between adjacent layers. A large stack is formed, various processing steps are performed on the access plane face of the large stack, and then the large stack is segmented to form a plurality of smaller, or short, stacks. Means are provided for causing separation of the larger stack into smaller stacks, without disturbing the adhesive which binds the layers within each small stack.

Abstract: This application discloses hardware suitable for use in a neural network system. It makes use of Z-technology modules, each containing densely packaged electronic circuitry. The modules provide access planes which are electrically connected to circuitry located on planar surfaces interfacing with such access planes. One such planar surface comprises a resistive feedback network. By combining two Z-technology modules, whose stacked chips are in planes perpendicular to one another, and using switching networks between the two modules, the system provides bidirectional accessibility of each individual electronic element in the neural network to most or all of the other individual electronic elements in the system.

Abstract: A method for determining the concentration of individual solutes in a body of liquid, e.g., measuring contaminants in waste water. A sparging IR process is used, in which gas in the form of minute bubbles moves upwardly in a non-flowing body of liquid. The gas remove vaporized samples of the subject solutes and flows to a gas cell, where it is subjected to infrared spectrometer analysis. The true concentration of each subject solute is measured by plotting its concentration values against elapsed time, and then extrapolating back to time zero to determine the initial concentration of the solute. In addition, the rate of depletion is used to determine the ratio of vapor pressure to solubility of the solute. Replotting the original data using logarithm values can simplify the extrapolation.

Abstract: A process is disclosed which applies advanced concepts of Z-technology to the field of dense electronic packages. Starting with standard chip-containing silicon wafers, modification procedures are followed which create IC chips having second level metal conductors on top of passivation (which covers the original silicon and its aluminum or other metallization). The metal of the second level conductors is different from, and functions better for electrical conduction, than the metallization included in the IC circuitry. The modified chips are cut from the wafers, and then stacked to form multi-layer IC devices. A stack has one or more access planes. After stacking, and before applying metallization on the access plane, a selective etching step removes any aluminum (or other material) which might interfere with the metallization formed on the access plane. Metal terminal pads are formed in contact with the terminals of the second level conductors on the stacked chips.

Abstract: A racing system for a group of exercise machines is disclosed. The race is entirely flexible, in that each exercise unit communicates electronically with all of the other potential racing units. Any user may offer a race, accept or reject another user's race offer, or join a race during a limited countdown period. More than one race can be underway. For cost reduction, a daisy chain hookup is used, in which each unit's microprocessor has an input port receiving message flow from the output port of the preceding unit, and an output port transmitting message flow to the input port of the following unit. The racing function is controlled by the same microprocessor which is embedded in each exercise machine as the controller for that machine, receiving commands from the user and feedback from the machine.

Abstract: An improved variable rate attenuator (VOA) is disclosed, which is used in an optical signal transmission system for testing (and other) purposes. In an optical fiber data transmission system, the VOA can be used to determine how much attenuation of the light beam can be tolerated without causing excessive bit error rate (BER) in data transmission. The improved VOA is a blocker having a vane-like structure which is gradually rotated into a collimated beam to cause attenuation. Because the movement vector of the edge of the blocker perpendicular to the collimated beam gradually becomes less for a given increment of blocker rotation, resolution of the attenuation is improved.

Abstract: A gas cell for use in spectrometric analysis is disclosed, in which a series of pipes provide both the gas chamber and a light guide for infrared radiation which passes through the gas to accomplish the analysis. The light pipe is designed to provide a maximum radiation throughput of a collimated radiation beam. The same pipe provides laminar gas flow into and out of the gas cell. In other words, the gas when moving is not obstructed or restricted by changes in the cross-sectional area of its passageway.

Abstract: A radiation guiding structure for incoherent radiation is disclosed in which a collimated beam is transmitted through a light pipe having high radition throughput. Radiation losses due to absorbance are minimized by: (1) matching the area of the beam and the light pipe passage; (2) minimizing the number of reflectances of a given ray by reducing the angular divergence of radiation in the beam; and (3) using a reflective coating on the wall of the light pipe which has the low point of its reflectance curve at a relatively high grazing angle.

Abstract: An ATR sample cell is disclosed, of the type incorporating a circular internal reflectance crystal. A flowing liquid sample has input and output ports in the IRE housing, or cell, which are offset from the axis of the circular IRE (or rod) sufficiently to direct the flow of liquid against the internal wall (usually stainless steel) of the flow jacket, rather than against the IRE. This tends to create a helical flow path from the input port at one end of the housing to the output port at the other end of the housing. In order to further control the sample flow path, and augment the spiraling effect, two further improvements are disclosed. The structure through which the sample material enters the sample chamber surrounding the IRE is designed to establish a spiraling motion of the liquid flow before it enters the sample chamber. Also, the inner cylindrical wall of the metal housing has a groove which forms a helical path from the input to the output end.

Abstract: A probe is disclosed for use in internal reflection spectroscopy at locations immersed in containers. Two parallel light pipes, located inside the probe, are used to carry radiation toward and away from an internal reflectance element (IRE) located at or near the bottom of the probe. The IRE, which is exposed to analyte in the container, has a radiation-entering surface and a radiation-exiting surface which permit collimated radiation to fill both light pipes. No beamsplitter is required to separate pre-sample and post-sample radiation. In one embodiment the IRE is a rod having concave conical entering and exiting surfaces, and a separate radiation-direction-reversing element is mounted on the tip of the probe. In another embodiment the IRE is itself a direction-reversing means mounted on the tip of the probe.

Abstract: An integrated circuit chip having a plurality of parallel channels, and a stack of such chips, are disclosed, in which the function of A/D signal conversion is accomplished in each on-chip channel. In order to satisfy the power and real estate limitations of the chip(s), a substantial part of the A/D conversion circuitry is located off-chip. Two devices are required in each channel on each chip, a precision comparator, and a storage register. These may be combined with an off-chip analog ramp, and an off-chip digital ramp. Certain on-chip performance enhancements are disclosed, which can operate either in the analog mode or the digital mode. One such enhancement is compensating for the voltage offset of each comparator. Another enhancement is reducing the duty cycle of each precision comparator, in order to lower power requirements. An important use for the disclosed concepts is the field of multi-layer Z-technology modules, having two dimensional photo-detector arrays.

Abstract: An external reflectance spectroscopy apparatus and method are disclosed in which maximum radiation througput is obtained by using a beamsplitter which reflects half of a collimated beam and transmits the other half. In order to obtain reliable results, the condition of perpendicular incidence on the sample is approximated (without limiting throughput) by providing a beamsplitter having an uneven number of reflecting blades and the same number of transmitting openings. Each reflecting blade is opposite to an open area having the same size and shape. The result is a substantial equalizing of contributions from rays polarized parallel to the plane of incidence and from rays polarized perpendicular to the plane of incidence.

Abstract: An infrared microscope is disclosed which provides illumination for reflectance by the sample. This illumination follows a path through the objective toward the sample, and again, after reflection, through the objective toward the detector. The reflectance illumination is directed toward the objective and sample by a fully reflective mirror, which injects approximately half of the interferometer beam into the microscope, and permits substantially all of the reflected beam to reach the detector.

Abstract: An interferometer structure is disclosed in which alignment problems are reduced by providing a special retaining structure for the transparent beamsplitter plates. In order to minimize distortion of the beamsplitter plates, the metal housing surfaces, against which they are held, are each coated with a material which has a very slippery and extremely flat surface engaging the surface of the respective beamsplitter plate. The preferred coating material is polytetrafluoroethylene. A glass tool (optically flat) is used during heating (and hardening) of the coating material, for the purpose of insuring an unusually flat coating surface.

Abstract: An apparatus and method for fluid sample analysis are disclosed which use a cylindrical internal reflectance element (IRE) having conical end surfaces. The divergence of rays inside the IRE is minimized by using reflecting cones at each end of the IRE, the structural elements and their dimensions being such that each entering ray strikes the conical IRE end surface at substantially the same angle of incidence. Means are included for providing optical stops at the large end of both the input and output reflecting cones, in order to eliminate any rays which might travel through the IRE without first being reflected by the input cone. Using such stops and properly dimensioning the entering diameter of the reflecting cone, result in a system in which each ray entering the IRE has been reflected once, and only once, by the reflecting cone.

Abstract: A high-density electronic module is disclosed, which is suitable for use as a DRAM, SRAM, ROM, logic unit, arithmetic unit, etc. It is formed by stacking integrated-circuit chips, each of which carries integrated circuitry. The chips are glued together, with their leads along one edge, so that all the leads of the stack are exposed on an access plane. Where heat extraction augmentation is needed, additional interleaved layers are included in the stacks which have high thermal conductivity, and are electrical insulators. These interleaved layers may carry rerouting electrical conductors. Bonding bumps are formed at appropriate points on the access plane. A stack-supporting substrate is provided with suitable circuitry and bonding bumps on its face. A layer of insulation is applied to either the access plane or stack-supporting substrate, preferably the latter. The bonding bumps on the insulation-carrying surface are formed after the insulation has been applied.

Abstract: An exercising apparatus is disclosed which simulates stair-climbing. In order to reduce breakage problems in the force-transmitting structure between each pedal and a one-way rotating drive shaft, a pair of pulley wheels, each associated with a pair of cables, are used. Each pulley wheel rotates the drive shaft, and is pulled in one direction of rotation by a pedal-connected cable, and in the other direction of rotation by a cable connected to a return spring. Each cable on each pulley wheel reels into and out of helical grooves formed in the periphery of the pulley wheel.

Abstract: An exercise apparatus is disclosed which simulates a stair climber, and which determines the amount of user exercise by the speed of rotation of a flywheel. The speed of the flywheel is controlled to maintain the desired speed of stair climbing by a friction belt engaging the flywheel. A rotary electrical motor is moved in one direction to tighten the belt on the flywheel and in the opposite direction to loosen the belt on the flywheel. A slack sensor determines whether the motor has been moved to a limit in the belt-loosening direction. Incremental changes of motor energy are used to gradually reduce an error signal between command speed and actual speed. Pulse width modulation is used to vary the motor energy in accordance with the size of the error signal.

Abstract: A multiplexer circuit is disclosed, for use with such signal sources as focal plane detector arrays, which contains a large number of parallel branches, each of which includes a transconductance MOSFET amplifier and a MOSFET switch of opposite channel polarity from the amplifier. The amplifier in each branch receives high impedance voltage signals orginating from its individual detector and converts them with high power gain into current signals which feed into the common output line whenever the switch in the same branch is turned on. The multiplexer branches, together with the multiplexer control logic, and other electronic devices, are all included on a signal IC chip which provides CMOS logic.