Abstract: For each pixel in an array of pixels in a fingerprint sensor, a fingerprint capacitor is defined by the fingerprint-bearing skin of a user's finger proximate to the top exposed surface of a sensing plate of the pixel. First and second plates are embedded in dielectric material beneath the sensing plate, and define therewith first and second capacitors of a sensing element. The capacitance of the fingerprint capacitor is coupled by the sensing element to an amplifier. During a sensing operation, the amplifier generates a pixel output signal that is a function of the variable capacitance of the fingerprint capacitor, which varies according to the presence of a fingerprint ridge or valley appearing directly above the sensing plate when the user's finger is in contact with the fingerprint sensor.

Abstract: For each pixel in an array of pixels in a fingerprint sensor, a fingerprint capacitor is defined by the fingerprint-bearing skin of a user's finger proximate to the top exposed surface of a sensing plate of the pixel. First and second plates are embedded in dielectric material beneath the sensing plate, and define therewith first and second capacitors of a sensing element. The capacitance of the fingerprint capacitor is coupled by the sensing element to an amplifier. During a sensing operation, the amplifier generates a pixel output signal that is a function of the variable capacitance of the fingerprint capacitor, which varies according to the presence of a fingerprint ridge or valley appearing directly above the sensing plate when the user's finger is in contact with the fingerprint sensor.

Abstract: A sensor for measurement of small-angle or small-displacement position incorporates multiple independent capacitors in a symmetric relationship. The device presents its output as a standard bridge configured differential signal, which can be interpreted and measured using conventional electronic demodulation means. The device includes an excitation array, a measurement array and an active rotor or linear array. The active array is coupled to a moving object and measured relative to the measurement and excitation arrays. The active array may be floating, grounded or driven by an electrical signal. However, driving the active array with signals sensed by the measurement array allows for reduced sensitivity to unwanted signals not in the measurement direction.

Abstract: A chip-type sensor against ESD and stress damages and contamination interference includes a substrate structure and a protection layer covering over the substrate structure. The protection layer includes, from bottom to top, a first layer for providing a first stress against the substrate structure, a second layer for providing a second stress against the substrate structure, and a third layer for providing a third stress against the substrate structure. The first stress and the third stress belong to one of a tensile stress and a compressive stress, and the second stress belongs to the other of the tensile stress and the compressive stress.

Abstract: Irrigation systems, moisture sensors and related methods having a sensor embedded in the ground to sense moisture and help control watering. The sensor is responsive to capacitance changes from ground moisture variations. The sensor uses spaced insulated electrodes which are mounted within a granular filled chamber within a water-permeable shell. The sensor is mounted as part of a ground unit that also includes a high frequency driver that excites the sensor. The ground unit further has a detector circuit which produces a moisture indicating signal based on the capacitance which varies with ground moisture. Also disclosed are controllers that electrically isolate the ground units so that reliable moisture signals can be obtained and used to control irrigation. The controllers can be configured to provide multiple zone operation using a shared controller having shared or independent moisture adjusters.

Abstract: A flexible framework supports electrically-conductive elements in a capacitive sensing arrangement. Identical frames are arranged end-to-end with adjacent frames being capable of rotational movement therebetween. Each frame has first and second passages extending therethrough and parallel to one another. Each of the first and second passages is adapted to receive an electrically-conductive element therethrough. Each frame further has a hollowed-out portion for the passage of a fluent material therethrough. The hollowed-out portion is sized and shaped to provide for capacitive sensing along a defined region between the electrically-conductive element in the first passage and the electrically-conductive element in the second passage.

Abstract: A fluid quality sensor (20) includes a first electrode (24) that has a fluid passageway (22) that is adapted to be placed in line with at least one fluid conduit (30). A housing (40) is supported on the first electrode (24) in one example by overmolding a portion (48) of the housing onto a portion of the first electrode (24). A second electrode (50) is supported within the fluid passageway (22) and electrically isolated from the first electrode (24). The first electrode (24) and the second electrode (50) operate as a capacitor for making fluid quality determinations.

Abstract: A method for measuring nm-scale tip-sample capacitance including (a) measuring a cantilever deflection and a change in probe-sample capacitance relative to a reference level as a function of a probe assembly height; (b) fitting out-of-contact data to a function; (c) subtracting the function from capacitance data to get a residual capacitance as a function of the probe assembly height; and (d) determining the residual capacitance at a z-position where the cantilever deflection is zero.

Abstract: Capacitance sensor electrodes are arranged in a form of matrix on a semiconductor substrate and coated with a cover film. These capacitance sensor electrodes are connected to a drive circuit. ESD electrodes are arranged in the vicinities of corner portions of the capacitance sensor electrodes. Each ESD electrode is composed of a film containing, for example, aluminum excellent in conductivity and a TiN film formed thereon. The ESD electrodes are grounded through the semiconductor substrate. On each ESD electrode, a plurality of fine ESD holes reaching the ESD electrode from a surface of the cover film are formed.

Abstract: Disclosed is a circuit-pattern inspection apparatus for inspecting a comb-shaped pattern 20 having an edge region formed as a plurality of finger pattern segments and a base region formed as an integral connection pattern segment, and a plurality of discrete patterns 30 each disposed between the adjacent finger pattern segments in a non-connecting manner and being not in connecting with the remaining discrete patterns. The inspection apparatus comprises means for supplying an AC signal alternately to either one of the finger pattern segments and both the finger pattern segments and the discrete patterns while maintaining the other at a ground potential, and sensors 131, 132, 133 for detecting the AC signal disposed in the edge region. The inspection apparatus can reliably detect the presence of defects in a circuit board without any difficulties.

Abstract: An RF power sensor for measuring power for an RF signal using capacitance includes a substrate preferably formed of a semiconductor, such as silicon or of a dielectric substance, a fixture part fixed to the substrate and forming a signal line and ground lines that transmit RF signals, and a bridge connected to the ground lines and floating over the signal line, wherein the bridge is driven by an external driving force, and the external driving force induces capacitance between the bridge and the signal line. Accordingly, power for an RF signal can be measured through the capacitance between the signal line and the bridge. The RF power sensor facilitates matchings, reduces insertion loss, and can be used in a wide bandwidth because it is based on transmission lines having characteristic impedance. Further, high power can be measured depending upon bridge designs.

Abstract: An inspection apparatus and method are disclosed. The inspection apparatus comprises a probe 30 having a width equal to or less than that of the layout pitch of conductive patterns 15 to be inspected, and a sensor section 20 having an area capable of covering the layout region of the conductive patterns. The probe 30 is adapted to be scanningly moved across an inspection-signal supply region including respective portions of the conductive patterns. The sensor section 20 is positioned opposed to the conductive patterns 15. An AC inspection signal is fed from an AC power source 35 to the probe 30 to form a capacitive coupling between one electrode or the conductive pattern, and the other electrode or the sensor section 20, and a detected signal from the sensor section 20 is amplified through an amplifier 25 to check the detected signal.

Abstract: Disclosed is an circuit-pattern inspection apparatus comprising a power supply element 30 adapted to be capacitively coupled with a parallel array of conductive patterns 20 to supply an inspection signal to one end of each of the conductible patterns, an open sensor 40 adapted to be capacitively coupled with all of the other ends of the conductive patterns to detect the inspection signal, and a short sensor 50 arranged at a position displaced from the power supply element 30 and adapted to be capacitively coupled with two lines of the conductive patterns to detect the inspection signal. The quality of the conductive pattern is inspected such that the presence of disconnection is determined when the detect signal from the open sensor 40 is largely reduced, and the presence of short is determined when the detect signal from the short sensor 50 largely rises and then falls. The circuit-pattern inspection apparatus can detect defects in a circuit board reliably and readily.

Abstract: A novel capacitive sensor assembly that utilizes a flex circuit for amplification of capacitively sensed signals and for separating the power, ground, and measurement signals is presented. The use of a flex circuit in the capacitive probe assembly allows implementation of multiple capacitive sensors for respectively capacitively coupling multiple signals from respective multiple test points of a circuit under test. The invention integrates the sensor plate, amplifier, and return wiring for each capacitive sensor all onto one flex circuit.

Abstract: For each pixel in an array of pixels in a fingerprint sensor, a fingerprint capacitor is defined by the fingerprint-bearing skin of a user's finger proximate to the top exposed surface of a sensing plate of the pixel. First and second plates are embedded in dielectric material beneath the sensing plate, and define therewith first and second capacitors of a sensing element. The capacitance of the fingerprint capacitor is coupled by the sensing element to an amplifier. During a sensing operation, the amplifier generates a pixel output signal that is a function of the variable capacitance of the fingerprint capacitor, which varies according to the presence of a fingerprint ridge or valley appearing directly above the sensing plate when the user's finger is in contact with the fingerprint sensor.

Abstract: The invention relates to a locator, in particular a handheld locator for detecting inclusions in walls, ceilings and/or floors, having a capacitive sensor device disposed in a housing, having means for generating a detection sensor of the at least one capacitive sensor device, having a control and evaluation unit, communicating with the sensor device, for ascertaining measurement values from the detection sensor, and having an output unit for reproducing measurement values of the capacitive sensor device. According to the invention, it is proposed that a measuring capacitor (16) of the capacitive sensor device (10) has a first electrode (21), which includes one face of the housing (14) of the sensor device (10).

Abstract: There is described a portable device (1) including in particular a case (2) closed by a glass (3) and containing device for detecting the presence of water (22) in contact with an external region of the assembly formed by the case and the glass. In a preferred embodiment, the device for detecting the presence of water include a plurality of capacitive sensors (20) arranged in a peripheral region of the device (1) so as to undergo a variation in their respective capacitances when the latter is immersed in water. Thus, a quantity characteristic of the capacitance value of each sensor (20) is periodically measured and stored. After each measurement, the new value obtained is compared to the preceding one to detect any variation in the corresponding capacitance. When a part of the capacitive sensors (20) simultaneously see their respective capacitances vary considerably between two measurements, detection of the presence of water is validated.

Abstract: A voltage probe includes a first signal lead configured to receive a first signal from a device under test, a first probe-tip network that is coupled to the first signal lead and that has a frequency response that includes a first transmission zero, a first compensation network that is coupled to the first probe-tip network and that has a frequency response that includes a first transmission pole, a second signal lead configured to receive a second signal from the device under test, a second probe-tip network that is coupled to the second signal lead and that has a frequency response that includes a second transmission zero, a second compensation network that is coupled to the second probe-tip network and that has a frequency response that includes a second transmission pole, and a differential amplifier circuit that is coupled to the first compensation network and to the second compensation network, and that is configured to provide a third signal that is responsive to the first signal and to the second sign

Abstract: An air interface apparatus is used for transmitting signals between an object under test and a probe device when the object under test is tested with the probe device. The air interface apparatus includes an inner conductor, an outer conductor which surrounds the inner conductor with a constant gap, a first signal pin being contacted to the object under test, a second signal pin being contacted to the probe device and inserted, an elastic spring for supporting the first and the second signal pins within the inner conductor, and an insulation ring for insulating the inner conductor and the outer conductor.

Abstract: An electrostatic capacitance sensor, includes an electrostatic capacitance detector, an operational amplifier in which a feedback impedance circuit is connected between an output terminal and an inverse input terminal of the operational amplifier, a signal line connected between the inverse input terminal of the operational amplifier and the electrostatic capacitance detector, an alternating-current signal generator connected to a non-inverse input terminal of the operational amplifier, and a shield for shielding at least a portion of the signal line, the shield being connected to the non-inverse input terminal of the operational amplifier and the alternating-current signal generator. The electrostatic capacitance detector includes a detecting electrode and a shield electrode. The detecting electrode includes a detector-detecting electrode for detecting an object to be detected and an electrode introducer-detecting electrode for introducing an electrode to the detector-detecting electrode.

Abstract: An electrode is made by turning a harness such that the electrode has a predetermined are for detecting capacitance. A method of manufacturing of an electrode includes step so turning a wire, and shaping the electrode with the wire. The electrode has a predetermined area for detecting capacitance.

Abstract: The gauge comprises concentric inner and outer tubes made of insulating material, with two capacitors each constituted by a set of electrodes, each set having at least one pair of two electrodes in strip form extending along the gauge and placed facing each other on the facing walls of the inner and outer tubes.

Abstract: A single cell fuel sensor (10) has a housing (12) including a fuel inlet chamber (14), a fuel mixing chamber (16) and a fuel outlet chamber (18). The fuel inlet chamber (14) includes an inlet orifice (20) leading into the mining chamber (16) at a given level and the fuel outlet chamber (18) includes an outlet orifice (22) leading out of the mixing chamber (16) at a second level that is spaced from the given level. An electrode (24) is fitted into the mixing chamber and electrically isolated from the housing (12), for example by a glass seal (26). In a preferred embodiment of the invention the housing (12) is an insert casting.

Abstract: A sensor includes a substrate consisting essentially of a non-conductive material, a first electrode, and a second electrode disposed on a first surface of the substrate, wherein the first electrode includes a first major portion traversing a length of the substrate and a finger extending from the major portion, wherein the second electrode includes a second major portion traversing the length of the substrate and a finger extending from the second major portion, wherein the first electrode finger extends toward the second electrode major portion and the second electrode finger extends toward the first electrode major portion and is substantially parallel to the first finger, and a third electrode connected to a ground, wherein the third electrode is interposed between and about the first and second electrodes.

Abstract: An apparatus for testing a dielectric property of a material constituting the interlayer dielectric of a flash memory device is formed by a layer (122) of the dielectric material disposed throughout a test structure (200) representative of the flash memory device and a plurality of conductors (117A, 117B, 117C) disposed within that layer (122) or a pair of planar conductors (402, 404; 502, 503; 504, 505; 506, 507; 508, 509) deposited such that the conductors (402, 404; 502, 503; 504, 505; 506, 507; 508, 509) are substantially parallel to each other and the layer (122) of dielectric material is disposed throughout a test structure (400, 500) so as to separate the conductors (402, 404; 502, 503; 504, 505; 506, 507; 508, 509), the test structure (400, 500) functioning as a capacitor. The apparatus may also test a conductive property of a material constituting the conducting lines of a flash memory device by disposing a conductor (801, 901) through the dielectric material (122).

Abstract: The present invention provides a cantilever which enables a further improvement of a surface resolution capability of a scanning capacity microscope (SCM) with regard to a cantilever employed for the SCM, as compared with a case of employing a conventional cantilever. As the cantilever applied to the SCM according to the present invention, that cantilever has a probe part 1 scanning a sample and an electrode part 2 supporting that probe part 1. Moreover, that probe part 1 includes an insulator 1a having a square pyramidal shape and a conductive wiring 1b placed only on one surface of that insulator 1a having the square pyramidal shape.

Abstract: A method for measuring the moisture content of skin, includes placing a probe on the skin for measuring the capacitance of the skin. An apparatus for applying the method, includes a probe and devices connected to the probe for transmitting, transferring and analyzing a signal. A wave signal is transmitted into the probe, the capacitance of the probe is measured by comparing the wave phases of the transmitted and reflected waves, and the applied radio frequency is low, approximately 0.2 to 5 MHz. The apparatus also includes a device into which a wave formed by the signal reflected from the probe is arranged to be led into a first input; and into which a wave forming the signal and transmitted to the probe is arranged to be led into a second input, whereat the capacitance can be measured by comparing the wave phases.

Abstract: The novel apparatus permits precise measurements of parasitic capacitances. The apparatus has a test structure and a reference structure, each with two conductor tracks. In the reference structure, the two conductor tracks are always at the same potential. In the test structure, one conductor track is coupled to ground potential and the other conductor track to a different potential. The test structure and the reference structure are connected to a voltage potential and the charge which builds up on the test structure and the reference structure is registered. The parasitic capacitance can be calculated precisely from the charge difference. The conductors of the test structure and of the reference structure are arranged in such a way that each conductor perceives a relationship to capacitive parasitic effects in the same environment.

Abstract: A capacitance type moisture sensor having the capability of accurately detecting amounts of water is provided. This sensor has a sensor housing having an electrically-insulating wall, a pair of electrodes disposed on the sensor housing, and a circuit unit. An outer surface of the electrically-insulating wall faces a space where the amounts of water should be detected. On an inner surface of the electrically-insulating wall, at least one of the electrodes is formed. An electric field developed between the electrodes is defined as a moisture detecting region. The circuit unit includes a capacitance detecting circuit for detecting a capacitance value between the electrodes, which changes in response to the amounts of water in the moisture detecting region, and an output circuit for providing an electrical signal corresponding toe the amounts of water according the capacitance value detected by the capacitance detecting circuit.

Abstract: An inexpensive RF test probe provides consistent monitoring of an RF signal while having minimal effect on the circuit under test. In one embodiment, an RF test probe comprises a return conductor and a probing conductor. The probing conductor is positioned within an insulator and a termination such as a 50 ohm resistor is electrically positioned between the ground conductor and probing conductor. The probe is used by placing a portion of the insulating material surrounding the probe conductor in contact with a circuit such as an RF microstrip carrying an RF signal to be monitored.

Abstract: A method and an apparatus for measuring the moisture content of the soil in order to enable pF value based control of irrigation in cultivation on the soil, as well as a method and an apparatus which use the first-mentioned method and apparatus to enable pF value based control of irrigation. To attain these objects, the invention provides a method for measuring the pF value (soil moisture tension) of the soil, comprising the steps of (a) preliminarily determining the correlation between pF value and volumetric water content of the soil to be measured, (b) measuring the volumetric water content of the soil, and (c) converting the value of the volumetric soil water content of the soil measured in the above step (b) to the corresponding pF value on the basis of the correlation between pF value and volumetric water content predetermined in the above step (a). Also a method and an apparatus for controlling the irrigation of the soil based on the measurement of the pF value by the method.

Abstract: A capacitive fingerprint sensor includes a polymeric protective coating defining a sensing surface and having conductive particles suspended therein. The conductive particles act as parallel strings of series capacitors to couple the capacitance the fingerprint-bearing skin of a user's finger applied to the sensing surface to capacitive sensing elements beneath the protective coating. The polymeric material of the coating is durable and scratch resistant. The conductive particles enable use of a protective coating of 10 to 20 microns in thickness while providing a high degree of sensitivity and image resolution.

Abstract: A method and sensor for determining the ratio of two components in a fluid mixture comprising a test cell in open communication with the fluid mixture and a reference cell containing a desired fluid mixture not in contact with the fluid mixture being tested, said reference and test cells having the same cell geometry. By use of a capacitance divider system, one determines the relative capacitances of said cells correlated with the dielectric constants of the respective fluid mixtures and ascertains the ratio of one component to the other component in the fluid mixture on the basis of the linear and monotonic correlation between the dielectric constant of the mixture at a given temperature and the ratio of one component to the other component. Preferably a mixture of methanol and water is tested such as for use as a feed to a reformer used in supplying hydrogen to a fuel cell. A fixed capacitor equivalent to the reference cell at a given temperature is usually substituted for the latter.

Abstract: A probe for non-destructive determination of complex permittivity of a material and for near field optical microscopy is based on a balanced multi-conductor transmission line structure created on a dielectric substrate member which confines the probing field within a sharply defined sampling volume in the material under study.

Abstract: The present invention relates to a system for nulling drive feedthrough error in a sensor having first and second drive electrodes which impart vibratory motion to first and second proof masses in response to first and second opposite phase drive signals, and having first and second capacitances defined between the drive electrodes and their associated proof masses. A mismatch between the first and the second capacitance is measured. Drive feedthrough caused by the measured capacitance mismatch is nulled by adjusting the relative amplitudes of the first and second opposite phase drive signals, whereby the ratio of the amplitudes is proportional to the ratio of the first and second capacitances. A servo loop may adaptively effect the ratio of amplitudes.

Abstract: An apparatus for monitoring deposition of a liquid-to-pasty medium on a substrate has a sensor fitted with two electrodes and an electronic circuit connected to the sensor for generating a signal which is characteristic of the substrate and the medium. The electronic circuit measures the imaginary component of the electrical permittivity of the substrate moving, together with the medium, between the two electrodes, and uses the measured value to determine the characteristic signal.

Abstract: A moisture content tester for non-destructive multipurpose testing that may be arranged in a drying apparatus or a testing box for proceeding a test of moisture content for an object to be tested and further have setting function for instructable water-containing rate is comprised of shell body, circuit plate, temperature compensation temperature-sensing bar, emitting pole, receiving pole, and controlling unit. A high frequency is emitted from the emitting pole and received by the receiving pole. Again, the received high frequency (sawtooth waveform) signal is transferred to the controlling unit through the circuit plate. The controlling unit then calculates the value of moisture content according to the received high frequency signal and the temperature value measured by the temperature compensation temperature-sensing bar. Further, the drying motion or displayed water-containing rate of the drying apparatus is controlled according to the value of moisture content.

Abstract: One embodiment of the present invention provides a system for capacitively probing electrical signals within an integrated circuit. This system operates by placing a probe conductor in close proximity to, but not touching, a target conductor within the integrated circuit. In this position, the probe conductor and the target conductor form a capacitor that stores a charge between the probe conductor and the target conductor. Next, the system detects a change in a probe voltage on the probe conductor caused by a change in a target voltage on the target conductor, and then determines a logic value for the target conductor based on the change in the probe voltage. In one embodiment of the present invention, determining the logic value for the target conductor involves, determining a first value if the probe voltage decreases, and determining a second value if the probe voltage increases.

Abstract: An apparatus for localized measurements of complex permittivity of a material is provided. A probe (10) analyzes the complex permittivity of a sample (11), the probe (10) having a balanced two conductor transmission line (12) formed of conductive segments (13 and 14). A probing end (15) of the transmission line (12) is brought within close proximity of sample (11) and an opposite end (16) of the transmission line is connected to a terminating plate (17) to form a resonator structure (18) for measurement of the complex permittivity of sample (11).

Abstract: A transmission electrode 10 and a detection electrode 12 are placed in an electrode section of a sensor and are capacity-coupled with a reception electrode placed on an opposed scale. Capacity change between the transmission electrode 10 and the reception electrode caused by displacement is detected with the detection electrode 12. A plurality of signals different in phase are supplied to the transmission electrode 10. The signal lines are wired like a zigzag using an upper layer and a lower layer and the distances between the signal lines and the detection electrode 12 are made substantially equal for making uniform the crosstalk amounts relative to the detection electrode 12.

Abstract: A method and apparatus for determining a volatility of a fuel sample. A fuel sample is collected in a container and heated for a time period using a heater device. Periodically during the heating, the capacitance of the fuel sample and the temperature of the heater device are determined. After a time period passes, the volatility of the fuel sample is determined using the capacitance decrease and the temperature increase. Specifically, a voltage across the heater device is used, along with the current through the heater device to determine the resistance of the heater device, which gives the temperature of the heater device and the sample. The capacitance and temperature are compared to values derived from experimentation for fuels of varying DI. The first measurement of capacitance with a known sample volume can be used to determine the MTBE or ethanol content in gasoline fuels.

Abstract: Invention relates to a capacitive proximity switch with an electrical bridge circuit for detecting of an electrically conducting face (15) approaching or moving away, wherein the electrically conducting face (15) is part of a capacitor (for example C1) of the bridge circuit, wherein at least one capacitor (C1, C2, C3, C4) and possibly at least one resistor (R9, R10) are disposed in the bridge branches of the bridge circuit as further reactances, and wherein the bridge is subjected to an alternating voltage as a bridge feed voltage (ubr). The proximity switch includes a flat multilayer printed circuit board (10) having at least two electrically insulating layers (13, 14), wherein an electrically conducting intermediate layer (11) as a first face of a capacitor is disposed between the two electrically insulating layers (13, 14).

Abstract: A capacitive sensor includes one or more chambers through which a material can flow. Two conductors are located to partially surround the flow chamber so that the material flows between the conductors. Where more than one chamber is used, additional conductors are provided. A measurement circuit connected to the conductors provides an output corresponding to a difference between test and reference frequencies. A display indicates the measured capacitance as a continuous-scale, proportional representation or a binary representation. The sensor system can measure volume charge density of a fluid or parameters responsive to changes in volume charge density, such as flow velocity.

Abstract: A capacitive sensor is shielded against external electric fields to maximize measurement accuracy. The sensor may include two coaxial, tubular conductors with a chamber between them into which a material sample to be measured is introduced. A measurement circuit connected to the sensor may include a reference oscillator that oscillates at a constant frequency and a test oscillator that oscillates at a frequency responsive to sensor capacitance. The circuit may display a value responsive to the difference between the test and reference frequencies. The circuit may also reverse the polarity of the signal applied to the sensor to minimize charge buildup, a phase-locked loop frequency measuring circuit, a temperature compensating circuit, and a non-linearity compensating circuit. The indicating circuit that displays a representation of the measured capacitance may display a continuous-scale or proportional representation or may display a binary or “go-nogo” representation.

Abstract: Method and device for monitoring an insulating or conducting test fluid for acidity, basicity, contaminants and/or specific chemicals by monitoring the rate of modification, for example corrosion, dissolution or erosion of at least one plate of a capacitive sensor immersed in the fluid. The sensor's dielectric element is inorganic or piezoelectrically active ceramic. Capacitor plates can be different materials, foil or coated/deposited metals modified by the test fluid. Capacitance is measured over time, its change due to modification of sensor plate area is recorded and used to determine quantity of acid, alkali, contaminants and/or chemicals in the test fluid. Piezoceramic dielectric allows the detector to be vibrated. The sensor can be attached to an ultrasonic transducer. Presence of specific chemicals requires a chemically non-reactive and a chemically reactive electrode re the chemical of interest. If the test fluid is conductive, the changed capacitance is measured in an insulating fluid.

Abstract: Devices, methods and systems are provided for monitoring of industrial processes. Devices and systems are provided which include a controller module connected to a probe module having a specified metallurgy and a resistor module having a specified resistance value which is capable of identifying the metallurgy of the probe module to the controller module. A resistor device including a resistor having a resistance value which identifies a type of metallurgical material is also provided. The devices and systems provided are inexpensive, portable, easy to set-up and operate by unskilled personnel, may be connected to both desktop and portable computerized devices and can provide real-time monitoring of industrial processes.

Abstract: A capacitance type moisture sensor having the capability of accurately detecting amounts of water is provided. This sensor has a sensor housing having an electrically-insulating wall, a pair of electrodes disposed on the sensor housing, and a circuit unit. An outer surface of the electrically-insulating wall faces a space where the amounts of water should be detected. On an inner surface of the electrically-insulating wall, at least one of the electrodes is formed. An electric field developed between the electrodes is defined as a moisture detecting region. The circuit unit includes a capacitance detecting circuit for detecting a capacitance value between the electrodes, which changes in response to the amounts of water in the moisture detecting region, and an output circuit for providing an electrical signal corresponding toe the amounts of water according the capacitance value detected by the capacitance detecting circuit.

Abstract: A non-contact measuring method and apparatus for producing a signal representative of a distance between facing surfaces of first and second parts, which are closely spaced apart such as the rotor and stator of an electric rotating machine. The method resides in positioning a sensor on the surface of the first part. The sensor includes first and second parallel, superimposed conductive plates electrically insulated from one another. The second plate is located in between the first plate and the surface of the first part. The first plate is fed with a high frequency signal through a resistance. A high impedance, low input capacity, unitary gain voltage amplifier is fed with the high frequency signal through the resistance. The second plate is fed with an output signal of the amplifier. The output signal of the amplifier is directly proportional to the distance between the two surfaces.

Abstract: The invention relates to apparatus monitoring the deposition of a liquid-to-pasty medium on a substrate and comprising at least one sensor fitted with two electrodes which are configured at a given, slight distance from the substrate surface and which apply an AC voltage to the substrate and medium, the substrate moving relative to the sensor, further comprising a test electronics connected to the sensor and emitting a signal which is characteristic of the substrate together with the medium.

Abstract: A sensor comprising: a substrate consisting essentially of a non-conductive material; a first electrode, and a second electrode disposed on a first surface of the substrate, wherein the first electrode comprises a first major portion traversing a length of the substrate and a finger extending from the major portion, wherein the second electrode comprises a second major portion traversing the length of the substrate and a finger extending from the second major portion, wherein the first electrode finger extends toward the second electrode major portion and the second electrode finger extends toward the first electrode major portion and is substantially parallel to the first finger; and a third electrode connected to a ground, wherein the third electrode is interposed between and about the first and second electrodes.