Abstract: A first gas in a laser cavity is ionized by an electrical discharge in the cavity as a step in producing an energy radiation. Debris (particulates) is produced during the formation of the energy radiation. The radiation and the debris move toward an optical element in the cavity. The optical element may be a window or a mirror. The debris tends to deposit everywhere in the cavity, including on the optical element, thereby dirtying the optical element. This inhibits the efficiency in the laser operation. A clean gas is directed into the cavity through a passage at a position displaced from the optical element. The clean gas then passes in the cavity through an orifice further from the optical element than the passage. The flow of the first gas through the orifice creates a venturi effect on the clean gas to insure that the clean gas will move away from the optical element. In this way, the clean gas inhibits the first gas and the debris from moving to the optical element.

Abstract: An apparatus and a method are provided for measuring component attentuation such as the attenuation in a splice of two (2) optical fibers. Four (4) fixed positions are provided. The second position is closer to the splice than the first position on one side of the splice and the third position is closer to the splice than the fourth position on the other side of the splice. Light emitters such as edge light emitting diodes are disposed at the first and fourth positions and light detectors such as ingass detectors are disposed at the second and third positions. The fibers may be looped at the four (4) positions to facilitate the passage of light into and out of the fibers. Clamps may be provided at each of the four (4) positions to provide for selective activation of individual ones of the detectors. In this way, light from each of the light emitters may be selectively passed at individual times to each of the detectors to provide indications at the detectors.

Abstract: A thermoplastic resin defines a core of a thermoformable thermoplastic composite material. The core is sufficiently thick to provide for a shaping of the composite material at an elevated temperature to any desired configuration. First and second layers of fabric material are disposed on opposite sides of the core. The fabric material may be formed of glass, carbon or aramid and may be formed from woven fibers, unidirectional or chopped fibers or random strand mats. The fabric layers have a thickness sufficient to impart strength and rigidity to the fabric material. Layers of a thermoplastic thermoformable resin material may be disposed on the layers of the fabric material. The thermoplastic layers impregnate the fabric layers, bond the fabric layers to the core and provide a smooth external surface to the composite material.

Abstract: Three delay lines may have common characteristics. The first delay line delays the rising edge of an input signal and a first inverter inverts this signal to provide a falling edge. A second inverter inverts the rising edge of the input signal to produce a falling edge which is introduced to the second delay line in a second path with the second inverter. The signals from the two paths may be introduced to a comparator which produces a control signal having logic levels dependent upon the relative times that the falling edges occur for the signals in the two paths. For example, the control signal may have the first logic level when the falling edge occurs first in the first path and the control signal may have the second logic level when the falling edge occurs first in the second path. The voltage from a charge pump is adjusted in accordance with the logic level of the control signal.

Abstract: A thermoformable thermoplastic composite material has a core sufficiently thick to provide for a shaping of the composite material at an elevated temperature to any desired configuration. Layers of a fabric material disposed on opposite sides of the core may be formed of glass, carbon or aramid and from woven fibers, unidirectional or chopped fibers or random strand mats. The fabric layers are sufficiently thick to impart strength and rigidity to the composite material. Layers of a thermoplastic thermoformable resin material may be disposed on the fabric layers. The thermoplastic layers impregnate the fabric layers, bond the fabric layers to the core and provide a smooth external surface to the composite material. The core is preferably thinner than the combined thicknesses of the fabric layers and the thermoplastic layers. For example, the thickness of each fabric layer may be 0.008"-0.009" of each thermoplastic layer may be 0.0005"-0.002" and of the thermoplastic composite material may be 0.035"-0.060".

Abstract: An anode and a cathode in a laser are spaced in a first direction. A voltage difference between these members produces an electrical discharge which ionizes gases in the laser to react chemically and produce coherent radiation. First and second tubes made from a dielectric material are spaced in the laser in a second direction transverse (preferably perpendicular) to the first direction. The anode, the cathode and the tubes extend through the laser in a direction transverse (preferably perpendicular) to the first and second directions. The tubes are preferably at least a 99.9% pure polycrystalline aluminum oxide ceramic with traces of other metallic elements than aluminum. Bushings made from a material homogeneous (preferably identical) to the tube material are integral with the tube near the opposite tube ends. First electrical conductors extend through the tubes.

Abstract: First and second ganged switches having first and second operative relationships are normally operative in the first relationship and are actuated by an external mechanism to the second relationship. In the first relationship, the first switch shunts and short circuits a pyrotechnic device and the second switch shunts and short circuits an energy storage member such as a capacitor. In the second operative relationship of the second switch, a battery charges the capacitor and also introduces a starting signal to an electronic timing circuit to institute a timing sequencer by the circuit for a pre-selected period that is selected via a series of inputs to the electronic timer. When the pre-selected time period has been timed out, the timing circuit introduces a signal to a solid state electronic switch which is normally in a non-conductive state to prevent actuation. The signal from the timing circuit causes the electronic switch to provide a low impedance.

Abstract: Two (2) optical fibers each having a core, a cladding enveloping the core and a buffer enveloping the cladding are spliced. First and second positions are adjacent the first fiber and third and fourth positions are adjacent the second fiber. The second and third positions are respectively closer to the splice than the first and fourth positions. Light emitters are at the first and fourth positions and light detectors are at the other positions. Light from each emitter is selectively passed to individual ones of the detectors. Members (e.g. solid gels) adjacent the emitters direct light into the associated fibers. Other members (e.g. solid gels) respectively between the first and second positions and between the third and fourth positions inhibit the light passage in the fiber claddings and buffers so that only the light in the fiber cores passes to the detectors. The gels and the fibers are clamped to provide matching dimples for trapping in the gels the light in the claddings and buffers.

Abstract: A static RAM cell having first and second differentially connected lines reads binary information stored in the cell by providing a current through the cell and the first line to read a binary "1" or through the cell and the second line to read a binary "0". First and second transistors in a pre-amplifier respectively connected in the first and second lines provide outputs respectively representing a binary "1" and a binary "0". The first and second transistors pass control currents respectively through third and fourth transistors to produce bias currents in one of the first and second transistors when reading currents are not passing through that transistor and the cell. The control of the third and fourth transistors increases the frequency at which information is read from the cell and is amplified. In this improvement, the bias current in the line providing an output at each instant is reduced by respectively providing a negative feedback from the outputs (e.g.

Abstract: This system measures the speed of an airborne vehicle relative to the surrounding atmosphere. The measurement is based on the scattering of pulses of coherent laser radiation, generated in the vehicle, preferably in the infrared region of the electromagnetic spectrum, by particles naturally present in the atmosphere at all times. The pulses are focused into the atmosphere at a sufficient distance from the vehicle, preferably 10-30 meters, to be beyond that region perturbed by the passage of the vehicle. The frequency of the radiation scattered by the particles differs from the frequency of the transmitted pulses by virtue of the relative motion of the vehicle and the atmosphere. Equipment in the vehicle digitally processes the received energy to determine this frequency difference for each pulse, and hence the component of the vehicle's velocity in the direction of the pulse transmission.

Abstract: A method wherein wafers are transferred between a loading chamber and a central vacuum chamber. A plurality of first vacuum processing chambers are disposed in a satellite relationship around the central chamber. A plurality of second non-vacuum chambers are interspersed with the first chambers in a satellite relationship around the central chamber. A second central vacuum chamber communicates with one of the first chambers through a valve. Third and fourth pluralities of chambers are disposed in a satellite relationship around the second central chamber to respectively perform functions similar to those performed by the first and second chambers, the fourth chambers being interspersed with the third chambers.

Abstract: An apparatus and method for scanning a probe over a surface to either produce a measurement of the surface representative of a parameter other than the topography of the surface or to perform a task on the surface. The scanning operation is divided into two parts and with a first scan to obtain and store topographical information and with a second scan to measure the parameter of the surface other than topography or to perform the task while the probe height is controlled using the stored topographic information.

Abstract: A two dimensional piezoelectric positioning device of the type including a thin walled cylindrical shaped member of piezoelectric material. A plurality of substantially rectangular shaped members are positioned around one surface of the cylindrical shaped member to form opposite pairs of electrodes to control the two dimensional movement in accordance with voltages applied to the pairs of electrodes. Each rectangular shaped member is split into at least two electrode portions and with particular polarity voltages applied to the individual electrode portions to maintain a substantially constant length for the cylindrical shaped member during the two dimensional movement.

Abstract: First binary bits are read synchronously relative to clock signals (e.g. 125 MH.sub.Z) from first memory positions and second binary bits are read from, or written in, second memory positions asynchronously relative to the clock signals without affecting the reading of the first memory bits. For synchronously reading the first bits, a plurality of channels are sequentially activated at a suitable frequency (e.g. 25 megahertz). Information from pairs of data lines are introduced into a pair of buses at the clock frequency. The information in the buses is sampled upon the occurrence of the first polarity in synchronizing signals having frequency (e.g. 62.5 MH.sub.3) derived from the clock signals and is prolonged and evaluated in a first pair of output lines upon the occurrence of the second polarity in the synchronizing signals. The information being evaluated is introduced to such output lines during the occurrence of the first polarity in the synchronizing signals.