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Introduction |
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Design of Quartz Resonant Sensors |
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Design of Pressure Transducers |
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Transducer Characteristics & Performance |
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Applications |
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The widespread use of digital computers and
digital control systems have generated a need for high accuracy, inherently
digital sensors. |
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This presentation will discuss the design,
construction, performance, and applications of resonant quartz crystal
pressure transducers. |
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Paroscientific is the leader in the field of precision pressure
measurement. The company was founded in 1972 by Jerome M. Paros after a
decade of research on digital force sensors. Application of this technology
to the pressure instrumentation field resulted in transducers of the
highest quality and superior performance. Precision comparable to the best
primary standards is achieved through the use of a special quartz crystal
resonator whose frequency of oscillation varies with pressure induced
stress. A quartz crystal temperature signal is provided to thermally
compensate the calculated pressure and achieve high accuracy over a wide
range of temperatures. |
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Piezoelectric
[pressure-charge generation] |
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Anisotropic
[direction-dependent] |
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Elastic Modulus |
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Piezoelectric Constants |
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Coefficient of Thermal Expansion |
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Optical Index of Refraction |
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Velocity of Propagation |
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Hardness |
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Solubility [etch rate] |
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Thermal and Electrical conductivity |
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Single Beam Force Sensors |
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Double-Ended Tuning Fork Force Sensors |
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Torsional Temperature Sensors |
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Paroscientific manufactures and sells a complete
line of high precision pressure instrumentation. Resolution of better than
0.0001% and typical accuracy of 0.01% are achieved even under difficult
environmental conditions. Other desirable characteristics include high
reliability, low power consumption, and excellent long-term stability. Over
30 full scale pressure ranges are available - from a fraction of an
atmosphere to thousands of atmospheres (3 psid to 40,000 psia). Absolute,
gauge, and differential transducers have been packaged in a variety of
configurations including intelligent transmitters, depth sensors, portable
standards, water level systems and meteorological measurement systems.
Intelligent electronics have two-way digital interfaces that allow the user
to adjust sample rates, resolution, engineering units, and other
operational parameters. Digiquartz® products are successfully
used in such diverse fields as hydrology, aerospace, meteorology,
oceanography, process control, energy exploration, and laboratory
instrumentation. |
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Notes