Abstract: A leak detector comprising a housing having an axis on first and second compartments spaced along the axis and hermetically separated by a partition, the first compartment being closed to comprise a pressure envelope which is in communication with an evacuated space to be monitored for leakage, an ionization cell in the first compartment providing an electrical current determined by gas in that compartment, hermetically sealed feed-through for enabling an electrical connection with the gauge, to the partition from the second compartment, an apparatus in the second compartment performing a control function in accordance with the current supplied by the cell.

Abstract: An improved drift tube wherein the high voltage electric field is generated as a function of atmospheric pressure. Such variation of the electric field provides good compensation for the effects produced by changes in atmospheric pressure. As a result, the identification of a particular compound at different altitudes is greatly simplified.

Abstract: Method and apparatus for detecting the presence of very small concentrations of certain vapors and gases in air or other gaseous backgrounds. A gas sample is ionized by a source of ionizing radiation. The ionized gas is then directed through a first drift region where the ions are subjected to a drift potential. Electrical biased grid means are provided to allow only heavier ions of lower mobility to pass through the first drift region into a second drift region, where electrical shutter means are provided to allow discrete packets of ions to pass and to drift at speeds depending upon their mobilities and be detected. In an alternate embodiment, the first draft region is positioned downstream from the second drift region.

Abstract: An anode assisted sputter etch and deposition apparatus having an electron source, a first anode adjacent the electron source and a second anode adjacent a negatively charged article to be sputter etched or sputter target in an ionizable gas atmosphere. Upon production of the electrons from said electron source a plasma is formed between the electron source, the first anode and the second anode, the plasma adjacent the second anode being capable of desorbing gases and other absorbed vapors from the surface of the article or target while positive ions from the plasma bombard the article or target with sufficient energy to eject material from the surface thereof.

Abstract: Method and apparatus for detecting the presence of very small concentrations of certain vapors and gases in air or other gaseous backgrounds. A gas sample is ionized by a source of ionizing radiation. The sample of ionized gas is then directed through a recombination region where ions are selectively recombined. The ionized gas is further directed through a drift region where the ions are subjected to a drift potential and separated into different groups, depending upon their mobilities. In an alternate embodiment, the ionized gas is first directed through a drift region, followed by a recombination region.

Abstract: An improved gas ionization cell with compensation for variations in flow rate of the gas and variations in radioactive source intensity. A gas sample is directed past a source of ionizing radiation and through a recombination region to an ion collection screen, where output current is monitored to give an indication of trace gases or vapors present in the gas under surveillance. Compensation for changes in gas flow rate and source intensity is provided by taking a portion of the gas subjected to the ionizing radiation and directing that portion of the gas through a channel by-passing the recombination region of the cell and past a pair of conductive probes. The first probe of the pair is biased at a predetermined voltage, while electric current is monitored at the second probe spaced downstream from the first probe.