| 摘要 |
An inexpensive glass capacitive pressure sensor. Conductive capacitor electrodes are disposed on two flat glass plates, one serving as a diaphragm, the other as a substrate. The electrodes are positioned in a spaced apart, substantially parallel relationship to form the plates of a parallel plate capacitor. The glass plates are sealed together with a sealing glass mixture to bound a volume between the conductors. The volume is at a reference pressure, preferably a substantial vacuum. Differences between the pressure to be measured and this reference pressure cause a flexing of the glass diaphragm which is detected by measuring the capacitance between the two electrodes. A suitable sealing glass mixture which provides a hermetic seal between the glass plates is comprised of, in weight percent, 8-10 SiO2, 1-2 Al2O3, 55-60 PbO, 7-9 PbF2, 7-10 ZnO, 4-6 CdO, and 10-15 B2O3. The sealing glass mixture must be vacuum fined to permit hermetic sealing within a vacuum.
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