Abstract: A spectrophotometric system includes an optical device for providing an optical path from a radiation generating means to a radiation receiving means. The optical device includes a substantially opaque layer which defines first and second coplanar face regions having different optical functions.

Abstract: An apparatus and method for coating a substrate with a thin film of material. The coating material is converted to a mist by means of an ultrasonic nebulizer and transported by a carrier gas to a chamber which contains the substrate where the mist is allowed to settle onto the substrate under the force of gravity. Sonic means are also provided to increase the settling rate of the mist droplets to lessen the settling time. Means are also provided to maintain the volume and concentration of the coating material in the nebulizer chamber over successive coatings.

Abstract: A currency discriminator for determining the denomination of a bank note or the like is disclosed. It includes a source of light directed at the note to be identified. A 2 mm.times.80 mm stripe is illuminated and the reflected light from the illuminated area is measured by a detector and converted into a digital representation. Synchronizing hardware permits 72 samples, each from a 2 mm.times.80 mm area, to be generated as a bank note is moved past the illuminator. The digital representations are then utilized to develop a four bit correlation number N where each bit is a one if (P.sub.n >P.sub.n-2), (P.sub.n >P.sub.n-4), (p.sub.n >P.sub.n-6), and (P.sub.n >P.sub.n-8) where P.sub.n is the present sample and P.sub.n-2, for example, is the second previous sample. The correlation number N is then compared with the corresponding number in a master list for notes of different denomination.

Abstract: An optical system for insertion into projection apparatus to permit viewing an image projected on an image plane without affecting its quality, size or position, including a beam-splitting element disposed in the optical path before the image plane which will transmit the radiation to the image plane and reflect a portion of the radiation reflected from the image plane in a direction which permits viewing, optical elements disposed in the optical path to correct for image displacement and aberrations caused by the beam-splitting element, said optical system being of unit power; according to one aspect of the invention the system is afocal so that it will remain at unit power when it is shifted longitudinally and the image position is insensitive to longitudinal displacement; and according to another aspect of the invention each element of the system is afocal so that the system remains at unit power and insensitive to changes in spacing between the elements.

Abstract: Circuitry for controlling the power output of an R.F. generator for regulating the forward power transmitted into a load of varying impedance, such as an R.F. sputtering target, and for limiting reflected power to a safe predetermined level. Forward power is controlled by circuitry that compares the voltage across the target with a predetermined reference voltage and the amplified output is applied to the signal generator control circuitry. Reflected power is measured by a sensor that outputs a proportional D.C. signal that is compared with a predetermined threshold voltage. Whenever the reflected power signal exceeds this threshold, it removes the effect of the target voltage input signal so that the amplified control signal to the R.F. generator is a function only of the reflected power.

Abstract: A structural element and method of fabricating a structural element having a zero expansion in a given direction. A bar member having left and right hand sections of positive and negative coefficients of thermal expansion is tuned so that expansion of one section is exactly offset by contraction of the other section in a varying temperature environments.

Abstract: Disclosed is a valve assembly having a housing defining a flow passage with an inlet port and a shoulder surrounding the port. The shoulder is chamfered in an upstream direction. A valve seat formed of a gold material, preferably 24 karet gold, is disposed on the shoulder. The margin of the seat about its central opening is deformed in an upstream direction against the chamfer. A sapphire ball seats against the deformed seat to seal the flow passage through the valve assembly.

Abstract: A very low absorption beamsampler for diffracting a very small fraction of a laser beam while specularly reflecting substantially all of the main beam with minimal absorption. The beamsampler comprises a plane mirror surface coated with a high-reflectivity multilayer dielectric coating, the topmost dielectric of which is grooved into a grating and coated with a transparent dielectric having a refractive index very similar, but not the same, as the grooved layer to form a weak phase grating for diffracting a weak first order sampling beam.

Abstract: A high power D.C. supply regulated for constant output power to be dissipated in varying loads such as encountered in cathode sputtering systems. A.C. input power is rectified to produce the desired D.C. The output D.C. voltage and load current are measured and a voltage signal proportional to their product is compared with a D.C. input control signal. The comparator "error" output signal controls a pass element that varies a D.C. current through saturable reactors in the A.C. input power lines to regulate the D.C. power into the load. The supply includes a limiting feature that is adjustable to a desired threshold level for limiting D.C. output power, voltage, and/or current so that the limiter will take control from the comparator to hold the supply output at a safe level.

Abstract: A self-bonding flame spray wire capable of forming a readily grindable coating formed of a sheath of aluminum and a compacted powder core containing a major portion of nickel and stainless steel and a minor portion of aluminum and metal oxide. The core may contain from about 10 to 90 percent, and preferably about 61 percent, by weight nickel, about 10 to 90, and preferably 30, percent by weight stainless steel, from 1 to 10 percent by weight, and preferably 5 percent by weight, aluminum, from 1/4 to 10 percent by weight, and preferably 4 percent by weight, of the metal oxide which may, for example, be cobalt oxide or zirconium oxide, and is most preferably zirconium oxide.

Abstract: Disclosed is a system for the measurement of the atomic absorption of gaseous samples including a reaction vessel and conduits for supplying liquid sample, carrier gas and a reagent to the vessel. A discharge conduit is coupled between the reaction vessel and the measuring cell of an atomic absorption spectrometer. The reaction vessel has a drain conduit and a relief valve in the drain conduit. Control means are provided for controlling the flow of liquid sample, carrier gas, reagent and gaseous sample through the corresponding conduits in accordance with the predetermined program for making consecutive measurements. A pressure sensor is provided for sensing pressure in the reaction vessel above a specified pressure indicative of incomplete draining of the vessel and below a specified pressure indicative of substantially complete draining of the vessel.

Abstract: The radii of two concave and two convex mirrors have the same absolute value. The two concave mirrors are placed back to back and have a central aperture. The two convex mirrors face the concave mirrors and also have a central aperture. An image at the apex of one of the convex mirrors will be imaged at unit magnification at the vertex of the other convex mirror if the spacing between the concave and convex mirrors is 0.866 times the absolute value of their radius. This system is corrected for all aberrations except astigmatism. Astigmatism is corrected by a double convex thin lens at the intermediate image at the vertices of the concave mirrors. Petzval curvature introduced by the field lens may be corrected by plano-concave lenses near the object and image planes. Alternatively identical shell lenses may be placed on either side of the intermediate image to correct for both astigmatism and Petzval curvature. The lenses may be achromatic doublets to correct for chromatic variation of field aberrations.

Abstract: The fluid flow switching apparatus includes a housing defining a chamber, a bore in communication with the chamber, fluid inlet and outlet ports respectively in communication with the chamber and bore, and a valve body movable within the chamber and carrying a sealing means for sealing about the bore. The valve body carries a pin which projects laterally into a cam track formed in the housing and which serves to releasably lock the valve body in a position enabling flow between the inlet and outlet ports through the chamber and bore and in a valve closed position preventing flow between the inlet and outlet ports. The valve body is movable manually between the valve open and closed positions by consecutive depressions of a push key connected to the valve body.

Abstract: The invention is directed to a dual-piston reciprocating pump assembly which includes two opposed substantially identical reciprocating pumps, a housing within which the pumps are mounted, a cam mounted on a cam shaft which is driven through a coupling by a stepping motor, each of the pumps including a piston assembly comprising a piston body having a piston end, the other end of the piston body being in the form of a yoke which is mounted for reciprocating motion in the housing, a cam follower carried between the arms of the yoke for engaging the cam face of the cam, a cylinder head having a piston cylinder therein for receiving the piston end, the housing having an end opening for receiving said cylinder head, a guide bushing mounted in the cylinder head for facilitating the assembly of the piston end, an inner bearing bore for the piston end disposed adjacaent the guide bushing, a high-pressure seal disposed adjacent the inner bearing bore, the piston end having substantial radial end play, and a piston sp

Abstract: Temperature sensitive photodetectors are temperature stabilized by coupling the photocathode of a photodetector in heat exchange relationship to a heated casting which acts as a heat source for the photocathode. The photocathode is coupled to the casting by a metallic Z-shaped bracket positioned on an insulating block with one base of the Z being coupled to the photocathode and the other base being coupled to a metal box through a Mylar insulating spacer, the box being directly mounted on the casting. A printed circuit board associated with the photodetector is also mounted on the insulating block. The direct heat path from the heated casting through the Z-shaped bracket to the photocathode reduces the warm up time of the photodetector thereby more rapidly temperature stabilizing the photodetector.

Abstract: Apparatus for clampingly supporting a source lamp in an optical, analytical instrument. The apparatus includes a heat distributing, metal corset encircling the lamp and a clamp member. The clamp is adjustably mounted in the instrument by a mechanism which permits rotational adjustment of the clamp about an axis perpendicular to the optical axis of the instrument and translational adjustment of the clamp along the same axis. The lamp is supported in the clamp in a stable configuration regardless of irregularities in its glass envelope.

Abstract: An improved photodetector arrangement comprises positioning a photodetector having at least one semi-transparent cathode so that the light beam striking the cathode passes through it at least twice before exiting from the photodetector. In another embodiment of the invention, a second photodetector is positioned relative to a first photodetector so that the light beam, after striking the first photodetector, strikes the second photodetector. Where the two photodetectors are employed, they may be electrically connected in parallel.

Abstract: In spectrophotometric apparatus in which there are a plurality of operating parameters a system for selecting predetermined combinations of operating parameters is provided, having as many user operable main mode selection stations as there are main modes in the design range of the system and having a mode multiplying system which is adapted to modify, in response to the operative state of user operable control means, each main mode selected out of at least some of the main modes in the range, for converting the selected main mode into an auxiliary mode.

Abstract: There is described a programmable gas flow control apparatus for use in atomic absorption spectroscopy. Essentially, an all pneumatic system is described which provides for a predetermined flow of fuel and oxidant to the burner. The invention compensates for the variation in oxidant flow due to nebulizer adjustments by adjusting the oxidant flow to the auxiliary inlet of the burner. The invention utilizes a pneumatic computing relay which senses the oxidant flow to the nebulizer and simultaneously adjusts the flow to the auxiliary inlet so that the total flow of oxidant satisfies the predetermined optimum rate. The constant monitoring of the nebulizer line by the computing relay allows for continual adjustment of the oxidant flow to offset subsequent adjustments.

Abstract: In order to obtain shorter exposure time and to obtain a longer life in x-ray lithography apparatus, an x-ray target made of tungsten is utilized and the apparatus operated to generate the tungsten M-line, this line being at a wavelength which will be absorbed by the resist normally used in lithography. To develop the resist, which was initially designed for use in an electron beam lithography, a developing method is used in which a initial short development with a high concentration is first carried out followed by a longer, full development with a concentration which is approximately the lowest at which complete development will take place.