Abstract: A phototherapy irradiation chamber having substantial uniformity of irradiance therewithin comprises an array of vertical fluorescent lamps surrounding the irradiation space. Reflectors are located within the array at the top and bottom thereof. The ends of the lamps extend beyond the reflectors.

Abstract: Electron microscope apparatus for electron beam microfabrication. A mounting is described for supporting at least the final lens assembly of an electron microscope column above the vacuum chamber which also provides a rigid mounting for a stage on which a substrate is located together with reflecting mirrors which co-operate with a laser interferometer system for measuring the distances moved by the stage and therefore the substrate in two orthogonal directions.To avoid unwanted movement between the mirrors and the interferometer heads, the latter are also carried by rigid support means on the underside of the mounting.The mounting may comprise a solid ring located in an aperture in the lid of the vacuum chamber.Alternatively, the mounting may comprise a rigid and reinforced plate forming the lid of the chamber, from the underside of which extend the rigid support means for the stage and interferometer heads.

Abstract: The ion-electron converter is primarily intended for the measurement of small positive ion currents. The essential feature of the converter is its curved conversion electrode which generates an electrostatic field with favorable ion-optical properties; in addition, it avoids high field strength at the conversion electrode, thus reducing spurious field electron emission. Both properties result in an ion detector of high efficiency and sensitivity for positive ions.

Abstract: A method and apparatus are disclosed for reducing scatter in diagnostic radiology and thereby improving image clarity and resolution, particularly in mammography or where abdominal organs are being studied. The method includes the use of a scanning multiple slit arrangement in conjunction with a conventional X-ray generator and imaging modality. A first or upper plate having a plurality of slits is placed between the patient to be X-rayed and the focal spot of an X-ray tube. A second or lower plate having corresponding number of slits, but substantially expanded in scale relative to the first plate, is placed beneath the patient but above the photographic cassette on which the X-ray image is to be recorded. The lower plate may consist of a bifurcated plate structure or a single, thick, slotted plate. The upper and lower slit structures are coupled together and are mechanically driven by a suitable drive mechanism to rapidly scan the patient with a group of separate beams produced by the upper slit plate.

Abstract: Apparatus and method for determination of residual stress in crystalline substances. An X-ray source is focused at two different, preselected angles with respect to a surface of a substance, and X-ray diffraction peaks are located with a single position-sensitive X-ray detector. The apparatus has positioning probes affixed to a base for maintaining the base in fixed relationship with the substance, and an arcuate glide channel formed in the base for controlled angular shifting of the X-ray source and detector. Residual stresses are determined more quickly than with prior art methods and apparatus having comparable precision because only a single detector is used, and because the detector locates diffraction peaks without time-consuming diffractometer shifting.

Abstract: A balanced ion emission system for "shockless type" static eliminators (wherein pointed discharge electrodes are capacitively coupled to one side of an A.C. high voltage source) employs pointed needles which are adjacently spaced from at least some of the pointed discharge electrodes and connected by way of a conductive path to the other side of the A.C. high voltage source. The points of the needles are adapted to be adjustably positioned with respect to the discharge electrodes so that an equal number of ions of each polarity are discharged into the atmosphere for impingement upon the articles to be neutralized.

Abstract: The specification describes a process wherein short wavelength or "hard" x-rays (less than about 4 Angstroms) are used to align a semiconductor processing mask with a semiconductor wafer without the requirement for thinning the wafer to permit the x-rays to pass through. These short wavelength x-rays may be obtained from either the continuum x-rays which accompany the "soft" (longer wavelength) characteristic x-rays used for resist exposure, or from a specialized source of hard x-rays. Alternatively, alignment marks may be provided on the surface of the wafer to project alignment-indicative fluorescent x-rays onto an x-ray detector without passing through the underlying semiconductor wafer. A null condition in the intensity of the "hard" x-rays, or the fluorescent x-rays in the alternative embodiment of the invention, which are received at an x-ray detector is indicative of an alignment between a reference mark on the mask and either a reference mark or an opening on the wafer.

Abstract: One of the isotopes of an element having several isotopes can be separated from the others in a dense, neutral plasma. Thus initially a neutral plasma is prepared including the element in question. This may consist of positive ions and negative electrons or alternatively of positive and negative ions, or else of a mixture of positive ions, negative ions and electrons. The plasma may then be injected into a magnetic field or may be generated in the field where more energy is imparted to a selected isotope than to the others. Finally, the isotopes are separated from each other on the basis of their differential energies. For example, the selected isotope may be given more energy than the others by stimulating it within the plasma at its resonant frequency which may be close to the cyclotron frequency, either by an electric field or by a magnetic field.

Abstract: The present invention relates to a new and improved tomographic visualization apparatus and method. The apparatus includes a camera with a stationary collimator of a radiation dense material with channels therein for collecting radiation from a body which passes through the channels in the collimator. The radiation is thereafter detected and the signal information is processed so as to provide images of selected depths within the body. The stationary collimator includes a plurality of matching sections wherein, the center lines of the holes or channels in each sector are parallel to each other and the angular position of their center lines are at a sloping angle in relation to the surface plane of the scintillation crystal of the camera. The center lines of the channels in one sector are not parallel to the center lines of those of any other sector but slope toward the common plane of intersection along the camera axis to provide matching tomographic collimator sections.

Abstract: An improved method and apparatus for transaxial tomographic scanning of a patient. A scanning system is provided having a rotatably mounted X-ray radiation source/detector pair which orbits and radially scans the patient in the plane of orbit. The source provides a plurality of beams of radiation having axes in the orbital plane. The beams pass through the patient to an array of detectors each of which is aligned with one of the beams. Radiation intensity data is collected at predetermined orientations of each beam/detector pair as the assembly orbits about the patient. In a preferred embodiment the rotatably mounted source-detector pair is rotated as a unit through a preselected rotation angle .phi. about an axis effectively passing through the source. The axis and the source-detector pair connected to it are then orbited around the patient through an orbit angle .gamma. while maintaining the preselected rotation angle .phi.. The axis is orbited about an origin lying in the orbital plane.

Abstract: The difference in concentration of a selected isotope in two materials is measured by directing beams of the materials toward the inlet of a mass spectrometer. A shutter is positioned in each beam to pass the two beams at predetermined different frequencies. The output signal from the mass spectrometer is applied to two synchronous detectors, each of which receives a reference signal representative of the frequency at which a respective beam is passed to the mass spectrometer. The output signals from the two detectors are compared.

Abstract: A method and an apparatus are disclosed for adapting a conventional quadrupole mass spectrometer to substantially simultaneously produce and record both positive and negative ions. The apparatus includes a control circuit for rapidly switching the repeller, source and lens electrodes of a quadrupole mass spectrometer between positive and negative potentials. This switching of the potentials, along with the selection of appropriately favorable ionization conditions, permits the generation of suitable streams of positive and negative ions. A dual electron multiplier detector is used for separately sensing the positive and negative ions transmitted through the quadrupole mass spectrometer. The disclosed method and apparatus are particularly suitable for obtaining accurate mass measurements using a quadrupole mass spectrometer.

Abstract: One of the isotopes of an element having several isotopes can be separated from the others in a dense, neutral plasma. Thus initially a neutral plasma is prepared including the element in question. This may consist of positive ions and negative electrons or alternatively of positive and negative ions, or else of a mixture of positive ions, negative ions and electrons. The plasma may then be injected into a magnetic field or may be generated in the field where more energy is imparted to a selected isotope than to the others. Finally, the isotopes are separated from each other on the basis of their differential energies. For example, the selected isotope may be given more energy than the others by stimulating it within the plasma at its resonant frequency which may be close to the cyclotron frequency, either by an electric field or by a magnetic field.

Abstract: Highly reliable measurement of degree of alloying of galvannealed steel sheets is carried out in order to fully control the continuous hot-dip galvanizing and galvannealing process on the basis of evaluation of a combination of two or more X-ray diffraction characteristics. Exact degree of alloying can be estimated without regard to fluctuations in the particulars of the material, the process conditions and the type of the product obtained.

Abstract: A system for accurately determining the exposure density required for x-ray photography of a particular area of interest is provided. The light received from an x-ray image intensifier is applied to a beam splitting mirror which divides the light between a motion picture film camera and a television film camera. Between the beam splitter and the motion picture film camera, there is positioned another light beam splitter to direct some of the light at a mask having an opening which encloses only the image area of interest. Behind that opening there is positioned a photomultiplier intensity sensor for determining the exposure required and varying x-ray beam intensity accordingly.

Abstract: A package intended for packaging industrial X-ray film in strip form is provided. It is particularly intended for X-ray examination of pipe-welds on the spot whereby the packaged film material is placed in a screw-like configuration around the weld to be inspected. The package permits edge-to-edge positioning of the film material.

Abstract: A radiant beam exposure apparatus forms a desired pattern on a workpiece disposed on a carriage movable in both directions X and Y which intersect at a right angle. The distance over which the carriage moves is measured by a laser interferometer. In response to the output of the interferometer, a pulse generating circuit generates one pulse for each n/m wavelength of laser light. The pulse signal is supplied from the pulse generating circuit to a memory device storing information corresponding to the pattern and at the same time to a deflection signal generator. Upon receipt of the pulse signal, the memory device reads out the information, and the deflection signal generator generates a deflection signal. The information signal is supplied from the memory device to a blanking signal generator.

Abstract: Sheet-like dielectric receptors which are to be exposed to object-modulated X-rays in the interelectrode gap of an ionography imaging chamber are attached to sheet-like carriers so that the carriers extend laterally beyond the reactors. The carriers are thereupon transported through the interelectrode gap and through successive stations of a xerographic printer which renders the latent imges of objects visible and subjects the receptors to other treatment. The carriers can be attached to receptors by resorting to an adhesive, by the application of electrostatic charges and/or by causing the marginal portions of the carriers to engage the receptors by suction.

Abstract: An angulometer for recording on film at the time of exposure, both the direction of an incident radiation beam and the angle which the beam makes with the normal to the plane of the film, the angulometer consisting of a radiation transparent plate within which is fixedly mounted perpendicularly to the plane of the plate a radiation opaque small diameter cylindrical rod which has its lower end coincident with the bottom surface of the plate. A set of concentric radiation opaque angulation indicator circles having a center common with the center of the rod are formed in the bottom surface of the plate, each successive circle of larger radius corresponding to a successively larger number of degrees of inclination of a radiation beam to the axis of the rod. In use, the device is placed on the X-ray film adjacent to the part to be X-rayed and left there during exposure. When the film is developed, the shadows of the radiation opaque concentric circles and rod appear.

Abstract: Infrared radiation from a laser is directed in part or intermittently through a sample containing a low concentration gas in a host gas. The other part or the interspersed radiation by-passes the sample. Emitted and transmitted radiation is separately detected and the ratio is formed representing relative transmission. The frequency of the laser is varied so that different frequencies but within the same absorbtion band of the gas to be detected are used. The relative transmissions for different frequencies are used to calculate electrically the concentration of the gas.