Abstract: An interferometer structure is disclosed which has an integrated central mirror unit, which constitutes an integrated alignment unit permitting complete prealignment before the unit is incorporated into the interferometer. The integrated unit carries the beamsplitter and two folding mirrors. Alignment is accomplished by adjusting the positions of the two folding mirrors around vertical and horizontal axes. Both the stationary mirror and the movable mirror, which control the radiation path lengths in the two interferometer arms, are retroreflectors. Because of the folding miirror effect, resolution of the interferometer spectrometer system is significantly enhanced.

Abstract: An apparatus for spectral analysis of chemical fractions is disclosed in which separate samples are frozen on a substrate, and infrared radiation passes through the sample either before or after it is reflected from a surface on the other side of the substrate from the sample. This permits radiation to move toward and away from the sample at the same side of the sample, thus simplifying the sample-cooling and sample-deposition techniques. The optical system is designed to defocus (and thus avoid detection of) unwanted radiation reflected by the sample.

Abstract: A high density electronic package is disclosed in which a stack of layer-like sub-modules have their edges secured to a stack-carrying substrate, the latter being in a plane perpendicular to the planes in which the sub-modules extend. Each sub-module has a cavity, inside which one or more IC chips are located. Each cavity-providing sub-module may be formed either by securing a rectangular frame to a chip-carrying substrate, or by etching a cavity in a single piece of material. In the latter case, the chips are mounted on the flat surface of one sub-module, and located inside the cavity of the next sub-module.

Abstract: A reflectance/transmittance structure is disclosed, which is adapted to be used in a microscope (primarily for infrared radiation) of a type disclosed in previous common inventor/common assignee applications. Radiation is passed through a Cassegrain objective lens on its way to the sample. It is reflected by a spherical mirror toward a flat mirror, then back to the spherical mirror, and then back through the sample on its way back to the Cassegrain objective lens. This arrangement permits retention of both the redundant aperturing and the injection mirror features of prior patent applications.

Abstract: A motor-driven exercise apparatus is disclosed, which incorporates a plurality of runaway-preventing features, thus reducing the chance of injury to the user. A motor control circuit is effectively controlled by pulse width modulated commands from a CPU, and by frequency-variable feedback information. These data are converted to voltages and input to a differential amplifier. A relay switch is used to cause immediate power turn off at both speed and elevation motors if any of the following occurs: (a) loss of feedback signal from the speed feedback at the CPU, (b) too rapid speed change sensed by the CPU, (c) failure of the motor control circuit to receive a signal from the CPU within a certain period, or (d) an elevation motor runaway sensed by the CPU.

Abstract: The present invention provides a radiation source which essentially matches the throughput radiation of the source to the throughput radiation of the interferometer; and it provides the maximum throughput usable by the interferometer with a minimum use of power at the source. The infrared source in this invention combines a radiating element having the optimum area with a hollow, inwardly-reflecting sphere, whose center is at the radiating element and whose exterior has a single aperture which causes radiation to fill the entrance field of view of the spectrometer.

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. Bonding bumps are formed at appropriate points on the access plane. A supporting substrate, formed of a light transparent material, such as silicon, is provided with suitable circuitry and bonding bumps on its face. A layer of insulation is applied to either the access plane or the substrate face, preferably the latter. The bonding bumps on the insulation-carrying surface are formed after the insulation has been applied. The substrated face is placed on the access plane of the stack, their bonding bumps are microscopically aligned, and then bonded together under heat and/or pressure.

Abstract: A method and related fixtures are disclosed which permit formation of stacks of thin circuitry-carrying layers. The layers terminate in an access plane having a two dimensional array of closely-spaced electrical leads. The method includes the steps of measuring the thickness of separate chips, selecting groups of chips having appropriate thicknesses, applying appropriate amounts of epoxy between adjacent chips, aligning the chips (and their electrical leads) in the direction parallel to their planes (i.e., the X-axis), and closing the cavity with an end wall which (a) exerts pressure on the stacked chips and epoxy in a direction perpendicular to the chip planes, and (b) establishes a fixed height of the stack in order to align the leads in the Y-axis. The final fixture provides a fixed-size cavity for confining the layers during curing of thermo-setting adhesive which has been applied between each adjacent pair of layers.

Abstract: A small ruggedized interferometer is disclosed, which can operate efficiently in spite of being subject to ambient mechanical vibrations. A prior art structure was analyzed to diagnose its performance deficiencies. The successful method is a step by step structural solution, beginning with the lowest frequency mechanical vibration resonance in the interferometer, restructuring to raise that frequency, then proceeding to the next lowest mechanical vibration resonance frequency in the interferometer, and so on. The movable mirror is carried by a parallelogram linkage. The minimum resonance in the present interferometer has been raised to approximately 1000 Hertz. A first (lowest) frequency resonance problem solved was due to the motor and its interface with the movable mirror. A second resonance problem solved was due to the vibration of the movable mirror itself.

Abstract: A safety latch construction is disclosed, of the type which has a rigid, pivoted slot-providing member secured to the doorframe, and a runner secured to the door having a T-shaped projection which engages the slot when the safety latch is operative, thereby limiting the amount of door opening movement. All of the parts are formed by stamping processes. No casting or machining is required. The doorframe member includes (a) a supporting member secured to the doorframe and having integral flanges providing pivot apertures, and (b) a pivoted member having an elongated slot formed between metal side bars which have projecting pivot pins and which are spaced at their pivoted ends, the resiliency of the side bars permitting the pivoted member to be readily assembled to the supporting member. An additional locking member provides a deadbolt feature.

Abstract: A photodetector sensing system is disclosed which combines staring and scanning features. By providing both temporal and spatial filtering, many system benefits are obtained. Each pixel in the viewed scene has a "dedicated" filter, which receives signals only from that pixel. By integrating time spaced signals from the same pixel, the filter maintains the staring effect of a two-dimensional detector array. A single detector may view a plurality of pixels, thereby improving resolution. A single pixel may be viewed by a plurality of detectors, thereby providing redundancy to correct for detector failures. The signal from each detector, after amplification, is first sent through a spatial, high frequency filter, and then is set to one of a plurality of parallel temporal, low frequency filters, which time share the detector. Synchronizing means are provided for ensuring that each temporal filter always receives its time spaced signals from the same source. Any suitable scanning mechanism may be used.

Abstract: A photo-detector array module is disclosed which comprises a stack of semiconductor chips having integrated circuitry on each chip. To permit the emplacement of photo-detectors on the focal plane end, and of thin film circuitry on the back plane end, each plane is etched to cut back the semiconductor material, then covered with passivation material, and thereafter lapped to uncover the ends of electrical leads on the chips.

Abstract: There is disclosed an adjustment structure for use in initially aligning the two arms of an interferometer, by varying slightly the angular position of mirror surfaces. Two "wedge" elements are used behind the mirror, each of which is independently rotatable about an axis perpendicular to the face of the mirror. In order to provide ideal lubrication between the relatively movable flat engaging surfaces, a solid layer of a low friction polymer is used, preferably polytetrafluoroethylene.

Abstract: A spectrometer system is disclosed in which the sample-containing chamber is a separately constructed, enclosed modular unit which is readily attachable to, and detachable from, one wall of a housing which constitutes the basic unit of the spectrometer, and which contains an interferometer, one or more detectors, and other portions of the system. Various examples of the essentially unlimited types of sampling modules are disclosed. Also, automatic sample loading and unloading devices are disclosed, which are feasible because of the modular construction. And means of loading and unloading samples without purge loss are disclosed, which are feasible because of the modular construction.

Abstract: A high-density electronic package module is disclosed which comprises a stack of semiconductor chips having integrated circuitry on each chip. To permit the emplacement of thin film circuitry on the access ends, each access plane is etched to cut back the semiconductor material then covered with passivation material, and thereafter lapped to uncover the ends of electrical leads on the chips.

Abstract: Spectrometer sampling chamber structures are disclosed which avoid purge loss during loading and unloading of samples. In two disclosed versions, a plunger carries the sample, and fits closely inside a fixed tube, into which it is inserted for sample illumination. Sample loading and unloading is accomplished without fully removing the plunger from the tube. Also, an automatic purging flow of gas from the interior of the spectrometer is caused during insertion of a new sample. In a third disclosed version, vertically stacked sample holders move through a vertical chute into which they are inserted to the top of the sample chamber, and from which they are removed at the bottom of the sample chamber.

Abstract: A method and related fixtures are disclosed which permit formation of stacks of thin circuitry-carrying layers. The layers terminate in an access plane having a two dimensional array of closely-spaced electrical leads. The method includes the steps of measuring the thickness of separate chips, selecting groups of chips having appropriate thicknesses, applying appropriate amounts of epoxy between adjacent chips, aligning the chips (and their electrical leads) in the direction parallel to their planes (i.e., the X-axis), and closing the cavity with an end wall which (a) exerts pressure on the stacked chips and epoxy in a direction perpendicular to the chip planes, and (b) establishes a fixed height of the stack in order to align the leads in the Y-axis. The final fixture provides a fixed-size cavity for confining the layers during curing of thermo-setting adhesive which has been applied between each adjacent pair of layers.

Abstract: A stabilized current source for integrated circuit use utilizes a linear ramp voltage across a capacitor to provide the desired current value in a "control" transistor which is in a current mirror relationship with a bias-current-providing transistor. The control and bias-providing transistors are "matched", in the sense that the ratio of the current value in one to the current value in the other remains the same at all times, provided they are subject to the same voltage. The linear ramp voltage across the capacitor causes a constant current to flow through the capacitor and the control transistor. The voltages across the control and bias-providing transistors are retained at the same value. Leakage at one voltage reference terminal of the bias-providing transistor is periodically compensated for by closing a switch between it and the corresponding reference terminal of the control transistor. Thus, the constant current in the control transistor is replicated in the matched bias-providing transistor.

Abstract: An accessory for use in the sample region of a spectrometer is disclosed which combines a matched pair of off-axis paraboloid reflectors having their focii optically imaged on the sample (either imaged at a common point or at two points which are optically imaged on each other) and having relative locations and orientations such that each ray of radiation strikes the two reflectors at points on the reflectors having approximately the same focal lengths. This arrangement involves the use of collimated optical beams into and out of the accessory. The accessory may function as a transmission-type accessory, in which the radiation passes through the sample, or as an internal reflectance accessory, in which the radiation passes through the sample holder but is reflected by the sample. The focal length relationship set forth is accomplished by having "back-to-back" paraboloid reflectors, i.e., their reflecting surfaces face in substantially different, preferably opposite, directions.

Abstract: An optical system is disclosed which significantly enhances the throughput of a grating spectrometer intended to determine impurity concentrations on the surface of semiconductor materials (usually single crystal silicon) used for integrated circuits. The system, which uses a laser beam as the photo-excitation means impinging on a Dewar-contained sample, includes a pre-sample series of lenses which so shapes the laser beam that its shape at the point of impingement on the sample is proportionally similar to the shape of the monochromator slit in the spectrometer. The same lens which provides final focusing of the laser beam on the sample also collects the sample-emitted radiation, which is thereafter focused by suitable optics on the monochromator slit, where it preferably substantially matches the shape of the slit, but slightly overfills the slit.