Detector Electronics Corporation

Kenneth M. Klapmeier and Bernhard G. Stinger Detector Electronics Corporation, 6901 West 100th Street, Minneapolis, MN 55438... 

International Pyrotechnic Society Seminar In Vail, Colorado July 6 thru 11, 1986 Ken M. Klapmeier of Detector Electronics Corporation, Minneapolis, Minnesota... 

Engineers-Architects, 68 Chemical Research Development and Engineering Center, 212 Department of Army, 234 Detector Electronics Corporation, 183 Hazards Research Corporation, 269 Morton Thiokol, 286... 

Before the third series of tests was made, additional research was required to find or develop an ultra-fast opening valve. This was the only major component that could be replaced to further reduce the response time. Information from Detector Electronics Corporation introduced us to a valve manufactured by Grinnell, called the Primac valve, which seemed to fit the bill. The valve uses a primer detonating device with redundant detonators to blow the valve open. The same electrical signal initiated by the ultraviolet sensor could now be used to actuate the detonators, thus further reducing lost motion. 

Figure 6.3 A fiber-optically coupled two-color flame detector assembly originally developed for military aircraft, but now used extensively to protect automotive paint robots where flames are a real danger. A two-color Si/Si sandwich photodetector and the electronics and logic are in the red brick. One fiber optic cable conducts radiation from a remote sensing site to the detector, and the other is used for thru-the-lens self-test. (Image courtesy of Detector Electronics Corporation.)...

Figure 6.4 Block diagram of the fiber-optically coupled system shown in Figure 6.3 See Hodges (1998). (Image courtesy of Detector Electronics Corporation.)...

Figure 6.5 A stand-alone flame detection device used by the semiconductor industry it uses two IR thermopiles, one tuned to a water band, and the other to broadband wavelengths, (hnage courtesy of Detector Electronics Corporation.)...

See Chromatography, Appendix BA.) Use a gas chromatograph equipped with a Thermal Energy Analyzer detector (Thermo Electron Corporation, or equivalent) and a 1.8-m x 3-mm (od) stainless steel column, or equivalent, packed with 20% Carbowax 20M, or equivalent, and 2% sodium hydroxide on 80- to 100-mesh, acid-washed Chromosorb P, or equivalent. Maintain the column at 170°. Set the injector port temperature to 220°. Use argon as the carrier gas, with a flow rate of 25 to 30 mL/min. Operate with a -110° to -130° slush bath. Adjust instrument parameters such as vacuum chamber pressure, oxygen flow, and calibration knob to obtain the proper sensitivity. 

High-precision isotope ratio mass spectrometers are designed with combinations of multiple Faraday cup detectors and multiple miniature electron multipliers (used as ion counters) for simultaneous isotope measurement. For example, the TRITON and NEPTUNE multicollector mass spectrometers from Thermo Electron Corporation can be configured with up to nine Earaday cups and eight ion counters to detect 17 ion beams simultaneously. Details of these instruments can be found at www.thermo.com. The use of multicollector instruments improves precision by two to three orders of... 

XPS Measurements. X-ray photoelectron spectra were acquired with a VG Thetaprobe spectrophotometer (Thermo Electron Corporation, West Sussex, U.K.) equipped with a radian lens, a concentric hemispherical analyzer, and a 2D channel-plate detector with 112 energy and 96 angle chatmels. A monochromatic Al Ka source with a spot size of400pm was used. Electrons were emitted at 53 with respect to the surface normak and the acceptance angle was 30. The instrument was operated in standard lens mode, and the analyzer in constant-analyzer-energy mode. Pass energies used for survey scans and detailed scans were 200 and 100 eV, respectively, for Au 4f, C Is, F Is, O Is, and... 

Detector TEA (Thermal Energy Analyzer nitrosyl specific). Thermo Electron Corporation Model 502, pyrolyzer 500°, carrier gas nitrogen at 5 mL/min, reaction chamber 0.6 torr, cryogenic trap -78°... 

R. Woldseth. X-Ray Energy Spectrometry Kevex Corporation, San Carlos, 1973. A good introduction with emphasis on detectors and electronics. Most of the applications refer to X-ray tube sources. Unfortunately the book is out of print, but many industrial laboratories may have copies. 

Gas Chromatograph -- A Varian 6000 equipped with two constant-current/pulsed-frequency electron capture detectors, a 30-m x 0.53-mm ID DB-5 fused-silica open-tubular column (1.5-/xm film thickness), and a 30-m x 0.53-mm ID DB-1701 fused-silica open-tubular column (1.0-/im film thickness), both connected to a press-fit Y-shaped fused-silica inlet splitter (Restek Corporation, Bellefonte, Pennsylvania), was used to analyze for the nitroaromatic compounds. The columns were temperature-programmed from 120°C (1.0-min hold) to 200°C (1-min hold) at 3°C/min, then to 250°C (4-min hold) at 8°C/min injector temperature 250°C detector temperature 320°C helium carrier gas 6 mL/min nitrogen makeup gas 20 mL/min. 

The photo-detector array module disclosed in US-A-4304624 (Irvine Sensors Corporation, USA, 08.12.81) comprises a focal plane array of detectors which is directly mounted, without a separate substrate, on an end of a module formed by a layered structure. Electronic components are mounted in "wells" in the layered structure. The method of fabricating the structure is claimed in the patent and the photo-detector mosaic array module is claimed in USA-4354107 (Irvine Sensors Corporation, USA, 12.10.82). 

When a detector array is connected to the side edges of a plurality of thin silicon substrates, which comprise signal processing electronics, there is a problem in forming interconnect bumps on the side edges of the silicon substrates. This problem is solved in US-A-5081063 (Harris Corporation, USA, 14.01.92) by an electroplating technique. 

See T.C. Harman J. Electron. Mater. 1, 230 (1972), for a report of a recent method and for references to methods developed earlier. Crystals for detectors are still grown often by methods closely related to the modified Bridgeman method developed originally by P.W.Kruse and coworkers in the early 1960s at the Honeywell Corporate Research Center see P.W.Kruse Appl. Opt. 4, 687 (1965)... 

Figure 7.4 Definition of time response characteristics of an electron multiplier detector. The initiating event is here assumed to be an effectively instantaneous ( delta function ) flash of light, but could equally well be a single charged particle. Reproduced from Photomultiplier Tubes Basics and Applications (3rd Edn), Hamamatsu Corporation, with permission.

Figure 7.5 Schematic diagram of an off-axis detector for a mass spectrometer. The conversion dynode is maintained at a high potential (up to 10-20 kV) thus accelerating the ions to high velocities to improve the secondary emission efficiency (the diagram is drawn to illustrate the airangement for positive ions). The secondary elections are then accelerated to the first dynode (maintained at 2 kV) and the SEM then amphfies the secondary electron current as usual. For negative ions the conversion electrode is maintained at a high positive potential and secondary positive ions are accelerated on to the first dynode. This example portrays a quadrupole analyzer with a discrete dynode SEM. Reproduced from Photomultiplier Tubes Basics and Applications (3rd Edn), Hamamatsu Corporation, with permission.

In their work Barrel1 and Ballinger examined two types of electron affinity detectors. The first was of the parallel plate type equipped with a 100 me titanium tritide source, mounted on a Jarrell-Ash Universal 700 gas chromatograph and the second which was of the cylindrical type consisting of a cylindrical 250 me titanium source cathode and a tubular inlet port anode obtained from Wilkins Instrument and Research Corporation. The latter detector required several modifications to obtain adequate response and stability. The most important modification consisted of a heater (Figure 141) to the detector chamber. The electron affinity detector, while not directly sensitive to aliphatic hydrocarbons, can be blocked and rendered totally insensitive by condensation of a heavy and relatively nonvolatile hydrocarbon film on the ionization source. A heater placed around the detector and maintained at a constant temperature of 150 to 180 0 is necessary for the long term stability of this detector. 

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