Abstract: A non-contact method of cleaning a surface comprising forming a thin gas film (10) of high velocity gas between a surface (14) to be cleaned and a cleaning device (16). The gas film (10), being also a gas bearing, supports the cleaning device (16) and thus forms a self-regulating gap (G) between the surface (14) and the cleaning device (16) so that the cleaning device (16) never contacts the surface (14). The cleaning device (16) comprises a plurality of bores (22) for directing gas onto the surface (14) and an opening (24) for vacuum. In the preferred embodiment, the bores (22) are arranged in a circle and the opening (24) is located centrally of the circle. The thickness of the gas film (10) is determined by the pressure of the incoming gas and vacuum. The creation of turbulence and eddy currents and the use of an ionized gas are enhancements to the cleaning ability of the gas film (10). The method includes moving the cleaning device (16) relative to the surface (14) and vice versa.

Abstract: A pneumatic bridge air gauge sensor. A measurement leg and a reference leg are used to measure a gap between a measurement probe and a surface. The two legs are initially balanced resulting in no air flow therebetween. A mass air flow sensor coupled between the two legs detects the mass air flow between the two legs resulting from a change in the gap distance from the balanced state.

Abstract: In a flow injection analysis apparatus, the flow of reagent to a measuring apparatus is generated by means of a peristaltic pump. A sample liquid which is contained in a loop of tubing is introduced into the flow of reagent by a change-over valve with the loop being connected in a conduit of a carrier liquid. The measuring apparatus measures the reaction between sample liquid and reagent. The peristaltic pumps are driven by stepper motors. The stepper motors are controlled by control electronics such that nonuniformities of the delivery of the peristaltic pumps caused by geometry are compensated by inverse nonuniformities of the angular rates. For that purpose the frequencies of the switching pulses are varied depending on position sensors.

Abstract: An improved adaptive optics system is disclosed for correcting atmospheric phase aberrations. A satellite (10) laser beacon is operated at the Stokes shifted Raman wavelength. After passing through the atmosphere (A), the signal is phase conjugated (16) and amplified in the Raman amplifier (12). The result is a high energy laser beam with phase conjugated aberrations which may be returned to the satellite (10).

Abstract: A plasma flame apparatus capable of self-extinguishing in the event of an unstable plasma discharge includes an inductively coupled plasma torch for producing a plasma flame which will have an acoustical signal characteristic of an unstable plasma discharge. A power generator is coupled to the plasma torch for powering the plasma. A microphone is receptive of the acoustical signal for effecting a representative electrical signal. A comparator generates a output electrical signal when the representative signal exceeds a selected level. The output signal is coupled to the power generator of the plasma flame such as to shut off the power generator when the representative signal exceeds the selected level.

Abstract: Laminated wafers with channels formed therein define a plurality of gas chromatographic columns in a body, with substantially minimal connecting channels between an injector and a detector. One or more of the columns at a time is selected by valve to be receptive of sample gas. Detector and injector cavities have surfaces with the adsorbent phase utilized in the column being further coated on the surfaces, whereby the detector and injector constitute an integral portion of the gas chromatographic column. A channel is formed between wafers each with grooves that have semicircular cross sections so as to form the channel with a circular cross section. A digital gas injector includes a plurality of chambers with respective measured volumes. Valves select one or more of the chambers at a time to be receptive of sample gas from the common inlet.

Abstract: A master disk is positioned such that a radial portion thereof is within a restricted field having good imagery of an optical projection system. A second blank disk is positioned such that the image location extends along a radial portion thereof. As the two disks are rotated synchronously a pattern in an annular area is formed on the blank disk replicating the master. Good imagery of the pattern is obtained with a simple system having an image field less than the size of the object being reproduced.

Abstract: A thermal spray gun, for spraying wire and powder simultaneously at high velocity to produce a dense and tenacious coating, comprises a nozzle and a gas cap extending from the nozzle. Combustible gas is injected from the nozzle coaxially into the combustion chamber in the gas cap. An annular outer flow of pressurized air is injected into the chamber adjacent to the gas cap. Heat fusible wire is fed axially from the nozzle into the combustion chamber. An annular inner flow of pressurized air is injected into the combustion chamber adjacent to the wire. Powder in a carrier gas is fed annularly from the nozzle into the combustion chamber coaxially between the combustible mixture and the inner flow, such that a spray stream containing the powder and the heat fusible material commingled in finely divided form is propelled through the open end.

Abstract: A lens mount including a lens cell wherein a lens is mounted through flexures. The lens seat in the lens cell has a radius of curvature match-mated to the lens surface which rests upon it. The rotational symmetry axis of the lens seat is coincident with the axis of rotation of the lens cell. The optical axis of the second lens surface is coincident with the axis of rotation of the lens cell.

Abstract: Disclosed are passive electrostatic particle collectors (10 & 12) for use in vacuum chambers (24 & 32) especially for a particle beam machine system (30 & 36) to collect particulates, such as dust and debris, generated by moving parts (16) within such chambers (24 & 32). These electrostatic particle collectors (10 & 12) comprise Tourmaline crystals (12) mounted on a bracket plate (10) and strategically located where dust and debris are generated. Also disclosed is a method of removing particulate material in vacuum chambers generated by moving parts by passive electrostatic particle collectors.

Abstract: An optical radar system for coherent ranging and velocimetry. Modulation of a laser diode by light backscattered from a target is used to determine distance and velocity of a target. An array of laser diodes are used to determine the velocity and topography of a target. Three laser diodes are used to determine speed and orientation of a rotating disk.

Abstract: The baseline drift occurring during a temperature or flow rate program in a chromatographic separating column is compensated for by signals from a function generator. The function generator supplies a computed baseline signal which is a representation of the baseline drift as an analytic function of the temperature, computed with specific separating column parameters. The parameters are determined in a prior test run and inputted into the function generator.

Abstract: A plasma gun apparatus with precision adjustment of arc voltage, includes a gun body with a bore therethrough, a nozzle anode in the bore, a cathode holder engaged in the bore with threads, and a cathode mounted on the cathode holder. A locking ring is engaged in the bore with threads for locking the cathode holder. An inner wrench is formed of a handle attached to a shaft inserted through a hole in the locking ring and engaged with the cathode holder to rotate the same for axial positioning. A sleeve wrench is disposed coaxially over the shaft and engaged with the locking ring. The handle and the sleeve wrench each has a plurality of angular position markings thereon mutually alignable to provide rotational reference for precision positioning of the cathode holder.

Abstract: An electrically heated tubular body fabricated of pyrolytic graphite in coaxial layers serves to atomize samples for analysis by atomic absorption apectrophotometry. Radially extending graphite rods engage the medial portion of the tubular body at diametrically opposed locations and constitute electrodes for passing an electric heating current transversely through the body. Owing to the characteristic anisotropy of electrical and thermal conductivity of the graphite layers, a relatively high electrical resistance to the current and an even temperature distribution along the length of the tubular body result.

Abstract: Iterative compensation of drift of peak positions of spectral lines is effected in a spectral monochromator including a grating, a detector of spectral fractions of a spectral band, a stepper motor for varying relative orientation of the grating and the detector, and a computer. Computer-defined spectral windows each encopasses a spectral band and has an initial spectral center. Each window is scanned to determine a peak spectral position. Calculation is made for determining a spectral position error of the peak position from the initial center for each corresponding window. A functional average of the offsets for the peaks is calculated as a linear function of window position, and a revised spectral center for each window is calculated as being equal to the initial center plus the functional average for the window position determined from the linear function. Each window is shifted correspondingly.

Abstract: An optical system wherein a mask pattern occurring at a predetermined period is imaged with a period less than the predetermined period. Spatial filter means are disposed within the optical system for permitting only the two (positive and negative) first orders of light from an illumination source diffracted by the mask pattern to pass therethrough.

Abstract: An apparatus for aligning a wafer. The edge of a wafer is mapped by means of a photodetector array and a light source to provide a signal representative of the X-Y position and angular orientation of the wafer as the wafer is rotated one revolution on a shaft. The signal is digitized and processed to provide stored information of the X-Y position and angular orientation of the wafer. The shaft is then rotated to move the wafer from its calculated angular orientation to a desired angular orientation. The X-Y positional information may be used to center the wafer.

Abstract: A system for feeding powder into high backpressure includes a carrier gas conduit with an orifice for entraining powder from a hopper, and a line for discharging feed gas at regulated pressure into the hopper to effect entrainment. A gas bleeder line has an outlet connection to the output carrier conduit, with a line pressure representative of carrier pressure. A differential pressure regulator equal to carrier pressure plus an increment. A regulated relief valve in the input carrier gas conduit provides a bleed gas supply to the bleeder line at a pressure equal to carrier pressure plus an increment. Pinch valves in the carrier conduit allow or prevent powder entrainment; alternatively, a rotatable sleeve is on the carrier conduit with a side opening alignable with the entrainment orifice. A carrier bypass conduit may be connected between the input conduit and the output conduit and hopper pressurization line may be connected between the output conduit and the hopper.

Abstract: A thermomechanical analysis apparatus includes a probe assembly supported in substantially weightless contact with a sample material over a range of displacement of the probe by means of a linear motor controlled from a constant current source. The probe assembly is automatically weighed by measuring and storing the value of the current needed to raise the probe, that value is thereafter employed during the analysis mode to maintain the probe assembly in a substantially weightless condition.

Abstract: An apparatus and method for the generation of patterns on large optics. A coating layer is deposited on the surface of a large substrate, whereupon a photoresist layer is deposited on the coating layer in relatively small localized areas. A flexible mask is fabricated embodying the pattern to be generated. This flexible mask is then aligned with any desired point on the substrate and brought into contact with the photoresist layer. The photoresist layer is then exposed and each localized area is developed and the underlying coating layer is etched. After the excess photoresist material is washed away the pattern, etched into the coating layer, remains.