JPS57179669A - Detecting device for change in electrostatic capacitance - Google Patents

Detecting device for change in electrostatic capacitance

Info

Publication number
JPS57179669A
JPS57179669A JP6425681A JP6425681A JPS57179669A JP S57179669 A JPS57179669 A JP S57179669A JP 6425681 A JP6425681 A JP 6425681A JP 6425681 A JP6425681 A JP 6425681A JP S57179669 A JPS57179669 A JP S57179669A
Authority
JP
Japan
Prior art keywords
circuit
electrostatic capacitance
change
time constant
measured
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.)
Granted
Application number
JP6425681A
Other languages
Japanese (ja)
Other versions
JPS6257227B2 (en
Inventor
Koichiro Miyagi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Anritsu Corp
Original Assignee
Anritsu Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Anritsu Corp filed Critical Anritsu Corp
Priority to JP6425681A priority Critical patent/JPS57179669A/en
Publication of JPS57179669A publication Critical patent/JPS57179669A/en
Publication of JPS6257227B2 publication Critical patent/JPS6257227B2/ja
Granted legal-status Critical Current

Links

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)
  • Measurement Of Resistance Or Impedance (AREA)

Abstract

PURPOSE:To measure the change in electrostatic capacitance in a stable and precise manner by a simple constitution and with little consumption of power, by measuring the capacitance intermittently based on the change in a time constant via a pulse signal and by holding a maximum measured value for a prescribed period. CONSTITUTION:A voltage according to a time constant at the time when a pulse signal from a pulse oscillating circuit 2 is impressed and a voltage according to a time constant of a comparing integrating circuit 4, which is delivered from this circuit based on the electrostatic capacitance of the circuit, a variable resistor R2 and a substance 1 to be measured, are compared by a differential operational amplifier 3, and thereby intermittent measurement is conducted. The maximum value of a compared voltage which changes according to a time constant corresponding to the electrostatic capacitance is held by a maximum signal amplitude value retaining circuit 5 until it is reset by a resetting circuit 6 controlled by the circuit 2, and display and recording theeof are conducted exactly even when a response time is long. Accordingly, the change in the electrostatic capacitance is measured in a stable and precise manner with little consumption of power by the aforesaid intermittent measurement by a simple constitution and by the holding of a measured value for a prescribed period.
JP6425681A 1981-04-30 1981-04-30 Detecting device for change in electrostatic capacitance Granted JPS57179669A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6425681A JPS57179669A (en) 1981-04-30 1981-04-30 Detecting device for change in electrostatic capacitance

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6425681A JPS57179669A (en) 1981-04-30 1981-04-30 Detecting device for change in electrostatic capacitance

Publications (2)

Publication Number Publication Date
JPS57179669A true JPS57179669A (en) 1982-11-05
JPS6257227B2 JPS6257227B2 (en) 1987-11-30

Family

ID=13252909

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6425681A Granted JPS57179669A (en) 1981-04-30 1981-04-30 Detecting device for change in electrostatic capacitance

Country Status (1)

Country Link
JP (1) JPS57179669A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03123884A (en) * 1989-10-06 1991-05-27 Beruko:Kk Detecting device

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6028481B2 (en) * 2012-09-14 2016-11-16 カシオ計算機株式会社 Moisture content determination device and program

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03123884A (en) * 1989-10-06 1991-05-27 Beruko:Kk Detecting device

Also Published As

Publication number Publication date
JPS6257227B2 (en) 1987-11-30

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