CA1281073C - Multi-frequency capacitance sensor - Google Patents
Multi-frequency capacitance sensorInfo
- Publication number
- CA1281073C CA1281073C CA000560915A CA560915A CA1281073C CA 1281073 C CA1281073 C CA 1281073C CA 000560915 A CA000560915 A CA 000560915A CA 560915 A CA560915 A CA 560915A CA 1281073 C CA1281073 C CA 1281073C
- Authority
- CA
- Canada
- Prior art keywords
- frequency
- circuit
- capacitors
- oscillations
- capacitor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 239000003990 capacitor Substances 0.000 claims abstract description 65
- 230000010355 oscillation Effects 0.000 claims abstract description 21
- 230000000694 effects Effects 0.000 claims description 2
- 230000014509 gene expression Effects 0.000 abstract description 11
- 238000000034 method Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 5
- 235000021251 pulses Nutrition 0.000 description 5
- 230000003071 parasitic effect Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 241000950314 Figura Species 0.000 description 1
- 101100001347 Mus musculus Akt1s1 gene Proteins 0.000 description 1
- 235000010627 Phaseolus vulgaris Nutrition 0.000 description 1
- 244000046052 Phaseolus vulgaris Species 0.000 description 1
- 235000001537 Ribes X gardonianum Nutrition 0.000 description 1
- 235000001535 Ribes X utile Nutrition 0.000 description 1
- 235000016919 Ribes petraeum Nutrition 0.000 description 1
- 244000281247 Ribes rubrum Species 0.000 description 1
- 235000002355 Ribes spicatum Nutrition 0.000 description 1
- SZKKRCSOSQAJDE-UHFFFAOYSA-N Schradan Chemical compound CN(C)P(=O)(N(C)C)OP(=O)(N(C)C)N(C)C SZKKRCSOSQAJDE-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 238000012163 sequencing technique Methods 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2605—Measuring capacitance
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Fluid Pressure (AREA)
- Measurement Of Resistance Or Impedance (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US083,781 | 1987-08-10 | ||
US07/083,781 US4794320A (en) | 1987-08-10 | 1987-08-10 | Multi-frequency capacitance sensor |
Publications (1)
Publication Number | Publication Date |
---|---|
CA1281073C true CA1281073C (en) | 1991-03-05 |
Family
ID=22180661
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA000560915A Expired - Fee Related CA1281073C (en) | 1987-08-10 | 1988-03-09 | Multi-frequency capacitance sensor |
Country Status (6)
Country | Link |
---|---|
US (1) | US4794320A (en]) |
EP (1) | EP0303442B1 (en]) |
JP (1) | JPS6471211A (en]) |
CA (1) | CA1281073C (en]) |
DE (1) | DE3887593T2 (en]) |
IN (1) | IN171716B (en]) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FI84666C (fi) * | 1990-02-07 | 1991-12-27 | Vaisala Oy | Maetkoppling foer smao kapasitanser. |
DE4039006C1 (en]) * | 1990-12-06 | 1992-03-12 | Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung Ev, 8000 Muenchen, De | |
US5088325A (en) * | 1991-02-11 | 1992-02-18 | Bindicator Company | System for indicating a condition of material |
DE4107366C1 (en]) * | 1991-03-08 | 1992-04-23 | Leica Heerbrugg Ag, Heerbrugg, Ch | |
US5539323A (en) * | 1993-05-07 | 1996-07-23 | Brooks Automation, Inc. | Sensor for articles such as wafers on end effector |
JP2932454B2 (ja) * | 1993-05-20 | 1999-08-09 | 三菱化学ビーエーエスエフ株式会社 | 複合成形体及びその製造方法 |
US5594353A (en) * | 1995-05-11 | 1997-01-14 | Elsag International N.V. | Method and apparatus for measuring the change in capacitance values in dual capacitors |
US5663506A (en) * | 1995-08-21 | 1997-09-02 | Moore Products Co. | Capacitive temperature and pressure transducer |
US5992240A (en) * | 1995-11-21 | 1999-11-30 | Fuji Electric Co., Ltd. | Pressure detecting apparatus for measuring pressure based on detected capacitance |
US5672808A (en) * | 1996-06-11 | 1997-09-30 | Moore Products Co. | Transducer having redundant pressure sensors |
JP2006071629A (ja) * | 2004-09-02 | 2006-03-16 | Ad Semicondutor Co Ltd | 静電容量変化検出方法及び検出集積回路 |
KR100828128B1 (ko) * | 2006-07-20 | 2008-05-09 | 에이디반도체(주) | 시분할 복수 주파수를 이용하는 정전용량 검출방법 및검출장치 |
EP2657713B1 (de) * | 2012-04-24 | 2018-08-01 | VEGA Grieshaber KG | Vorrichtung und Verfahren zur Bestimmung einer Messkapazität |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2937369A (en) * | 1955-12-29 | 1960-05-17 | Honeywell Regulator Co | Electrical signal measuring apparatus |
US3716782A (en) * | 1971-06-03 | 1973-02-13 | J Henry | Capacitance gage for measuring small distances |
GB2006970B (en) * | 1977-09-23 | 1982-03-31 | Testut Aequitas | Capacitance measuring device |
FI54664C (fi) * | 1977-10-14 | 1979-01-10 | Vaisala Oy | Elektronisk omkopplingstroemstaellare i synnerhet foer telemeteranvaendning i sonder |
US4193063A (en) * | 1978-05-15 | 1980-03-11 | Leeds & Northrup Company | Differential capacitance measuring circuit |
US4295091B1 (en) * | 1978-10-12 | 1995-08-15 | Vaisala Oy | Circuit for measuring low capacitances |
FR2454083A1 (fr) * | 1979-04-09 | 1980-11-07 | Facom | Dispositif de mesure de la position relative de deux objets |
AT367211B (de) * | 1979-08-29 | 1982-06-11 | List Hans | Kapazitiver messwandler |
DE3143114A1 (de) * | 1980-11-07 | 1982-07-15 | Mestra AG, 4153 Reinach | Verfahren und schaltung zur messung von kapazitaeten |
US4558274A (en) * | 1983-09-14 | 1985-12-10 | Johnson Service Company | Apparatus and method determining the value of a capacitance |
NO852169L (no) * | 1984-05-31 | 1985-12-02 | Vaisala Oy | Fremgangsmaate for maaling av kapasiteter, saerlig av lav verdi. |
FI70753C (fi) * | 1984-05-31 | 1987-01-07 | Vaisala Oy | Foerfarande foer maetning av kapacitanser, speciellt smao kapacitanser. |
US4633168A (en) * | 1984-11-30 | 1986-12-30 | Borg-Warner Corporation | Measuring system for determining the reactance ratio of a pair of reactive devices |
-
1987
- 1987-08-10 US US07/083,781 patent/US4794320A/en not_active Expired - Lifetime
-
1988
- 1988-03-09 CA CA000560915A patent/CA1281073C/en not_active Expired - Fee Related
- 1988-07-27 IN IN538/MAS/88A patent/IN171716B/en unknown
- 1988-08-09 DE DE3887593T patent/DE3887593T2/de not_active Expired - Fee Related
- 1988-08-09 JP JP63197279A patent/JPS6471211A/ja active Pending
- 1988-08-09 EP EP88307352A patent/EP0303442B1/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
DE3887593D1 (de) | 1994-03-17 |
IN171716B (en]) | 1992-12-19 |
EP0303442A3 (en) | 1990-07-25 |
EP0303442A2 (en) | 1989-02-15 |
JPS6471211A (en) | 1989-03-16 |
EP0303442B1 (en) | 1994-02-02 |
US4794320A (en) | 1988-12-27 |
DE3887593T2 (de) | 1994-08-18 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
MKLA | Lapsed |