Abstract: An aerosol sampling device and method are disclosed having improved sample flow characteristics. Sample flowing through an inlet nozzle is heated prior to discharge from the nozzle toward a measurement area to maintain sample flow more nearly laminar by compensating for the adiabatic cooling that occurs due to acceleration of flow through the nozzle. In addition, heating of the sample flow prevents condensation which can result with ambient air having a relative humidity of fifty percent. An optical particle measuring apparatus is shown having a generator for providing a laser beam, the path of which is through a measurement area, and an inlet nozzle through which aerosol sample is injected into the measurement area, after heating in accordance with this invention, to allow operation of the laser at a relatively high Q by reducing non-laminar flow characteristics.

Abstract: An apparatus for determining the intensity of radiation passing through an object as a set of planar beams from a radiation source is disclosed. The radiographic apparatus includes a detector array of adjoining scintillators having wall linings suitable for absorbing radiation, thereby functioning as self-colliminating detectors. The apparatus is also capable of counting the number of individual photons of primary radiation passing through an object along each path from a radiation source operating at the very high count rates used in computer-assisted tomography applications.

Abstract: An improved rotary plug valve which has a housing having an axial, tapered inner wall forming a tapered inner cavity, with a plurality of radial openings in a transverse plane, at selected angles, leading into the tapered inner cavity. A rotatable tapered plug is adapted to fit inside the tapered cavity, and having "0" ring seal means to seal the outer surface of the plug to the inner wall of the housing. Selected conduits through the plug provide means to control flow of liquid entering one or more of the openings in the housing, to flow through the plug to other selected openings, dependent on the anular position of the plug. The cavity is closed by top and bottom closures. The rotor has an axial shaft, by means of which it can be rotated exteriorly of the valve, by the passage of the shaft up through the center of the top closure.

Abstract: An indicator is made to fit within American Gauge Design dimension requirements to be compatible with existing accessories for indicators and still have a spindle with a travel of about 1/2 inch cooperating with an electro-optical, digital electronic measurement and readout system. A coupling is secured to the inner end of the spindle and supports a ruled glass scale for movement with the spindle in an axially offset position to move relative to a reader assembly that is mounted in the housing. A connecting arm is secured to the coupling for movement in a region spaced from the scale, a lifter rod is arranged opposite the spindle, and a lifter arm is connected between the lifter rod and the connecting arm so that the lifter rod moves about one-half the distance of the spindle. The connecting arm also prevents rotation of the spindle to maintain the orientation of the scale relative to the reader assembly.

Abstract: A digital electronic micrometer eliminates backlash and other error between a movable probe and a digital readout and arranges all the working components within a handle thermally insulated from the probe and the yoke. An optical scale is secured to the probe to move directly with the probe past an electro-optical reader arranged within the tool handle, and a manually operable retractor moves the probe away from the anvil against the bias of a spring. Electronic circuitry and digital display can also be arranged in the tool handle for indicating positions of the probe relative to the frame, and the circuitry includes manually actuatable hold circuitry for maintaining the display at an indication of a previous position of the probe after movement of the probe. This allows the tool to be moved to an orientation for observing a measurement previously taken when the tool was in a position obscuring the reading.

Abstract: Apparatus for measuring which is adapted for use with a remote digital readout. The measuring apparatus includes an elongated main beam and a measuring device slidably mounted on the beam. The beam includes a transparent ruled scale with markings positioned thereon corresponding to different measurements. Mounted within the device is an electro-optical decoder suspended by a unique flexure arrangement which detects marks as the device is slidably moved on the beam and produces electrical signals which are provided to the remote digital readout system which in turn produces a visual readout of measurement. The measuring device includes a second reader scale having similar markings thereon.

Abstract: Method and apparatus for orienting and measuring fibrous particles by conducting longitudinally oriented fibrous particles through a beam of radiation and measuring the radiation scattered in a direction aligned with the length of such particle and, independently, also measuring the amount of radiation scattered transverse to the length of the particle. Preferably, the measurements are accomplished utilizing a sensor having an inactive center portion substantially corresponding to the area of undisturbed beam of radiation, a first photosensitive area in a portion of the sensor aligned with the length of the particles, and a second, independent photosensitive area transverse to the length of the particle. Signals generated by the two photosensitive areas are added to determine the size of the particles, and the ratio between the signals is established to determine the aspect ratio of the particle.

Abstract: Method and apparatus for establishing a valid sample volume in a beam of radiation, wherein a sample stream is introduced substantially transversely to the radiation beam, an optical system is configured to produce images on first and second image planes, the two planes preferably being perpendicular to one another and established by means of a beam splitter, first and second photosensors being positioned in the image planes, the first photosensor having greater optical and an electronic gain and a masked portion, and the second photosensor being either unmasked or having masked portions corresponding generally to the unmasked portions of the first photosensor, the first photosensor being connected to comparator means and the second photosensor also being connected to the comparator means which accepts data only when the signal from second photosensor is of a greater magnitude than the signal from the first photosensor, whereby images on the photosensors from points outside the selected sample volume will be

Abstract: Two-dimensional data may be acquired at extremely high rates by means of a linear sensor array, and ganged shift registers with each sensor associated with at least one shift register. The state of each sensor is sampled periodically in accord with a selected, relatively high clock frequency and each sampling is sequentially recorded in the shift register associated with a specific sensor. A first dimension is provided by the linear nature of the sensor array and the second dimension is supplied by the sampling clock frequency as a subject moves past the sensor array. In a more advanced embodiment, the sampling operates only during the occurrence of an event and data is cyclically recorded in one group of shift registers at a rapid rate while previous data is unloaded from an alternative group of shift registers at a conventional rate.