Abstract: In a method and an arrangement for acoustic determination of an instantaneous fluid temperature, acoustic velocity V in a fluid is monitored and an output signal related to the acoustic velocity is generated. A conventional temperature sensor senses a fluid temperature TS and generates an output signal related thereto.

Abstract: An apparatus for detecting the temperature of a room (2) includes means (4) for generating and receiving sound waves, means (5) for determining the transit time of the sound waves for a certain distance (x) in the room (2) and means (10) for calculating the temperature (U) of the room (2) by means of the ascertained transit time (t) of the sound waves for the distance (x) in the room (2). An approximation procedure for ascertaining the distance (x) is automatically executed. The temperature (U) ascertained in that way corresponds to a mean room temperature over the distance (x).

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: A system for controlling process temperatures for semi-conductor wafers comprises a heater to heat the wafer, an element to generate a plurality of ultrasonic vibrations in the wafer, a Sagnac interferometer adapted to sense the ultrasonic vibrations and generate a wafer temperature signal responsive thereto, a system to calculate the wafer temperature on the basis of the generated wafer temperature signal, and a control element the wafer heater on the basis of the calculated wafer temperature.

Abstract: A passive sensor system utilizing ultrasonic energy is disclosed. The passive sensor system includes at least one ultrasonically vibratable sensor and an ultrasonic activation and detection system. The sensor has at least one vibration frequency which is a function of a physical variable to be sensed. The ultrasonic activation and detection system excites the sensor and detects the vibration frequency from which it determines a value of the physical variable. The sensor includes a substrate having at least one cavity therein, and a vibratable membrane overlying the cavity. Another preferred embodiment of the sensor is a compensated sensor pair including a first sensor whose vibration frequency is responsive to the physical variable to be sensed, and a second sensor whose vibration frequency is non-responsive to the physical variable to be sensed.

Abstract: The temperature of a support which rotates with a predetermined angular velocity about a rotational axis is measured. One of more temperature sensors are thermally coupled and rotate with the support. A measurement configuration with an electronic evaluation circuit is assigned to the temperature sensor. The temperature sensor has a ferro-magnetic or paramagnetic material, the magnetic susceptibility of which depends on the temperature according to the Curie law or the Curie-Weiss law. The measurement configuration has a magnetizing device assigned to the temperature sensor and a detector device which is fixed relative to the rotating support. The detector device delivers a measurement signal proportional to the temperature of the support when the temperature sensor passes by the detector device.

Abstract: An electronic chef's fork is provided which displays indicia such as food type and degree of doneness for a selected food type and temperature and which includes control areas by which the user of the electronic chef's fork selects the meat type. The operational circuitry of the device allows the user to select among an array of food type options and to thereby designate a degree of doneness for the selected type of food. A prompt message is provided to indicate the degree of doneness attained for the selected food type when the device is inserted into the food.

Abstract: A method is described for measuring localized operating temperatures and voltages on an integrated circuit. The integrated circuit includes an oscillator circuit with a frequency that varies with temperature and/or applied voltage. The frequency of the oscillator is then determined, using a constant voltage, for a number of temperatures to establish a known relationship between oscillation frequency and temperature. Once the relationship is known, a similar oscillator is included within or adjacent a second circuit of the integrated circuit. The operating temperature or operating voltage of the second circuit may then be determined by monitoring the frequency of the oscillator while the second circuit is operational.

Abstract: A method for measuring the temperature of a metallurgical furnace. An empirical relationship is established that connects the temperature, an operating parameter of the furnace that is causally connected with the generation of acoustic noise, and a representative acoustic noise frequency. Preferably, the relationship is based on modeling the gas phase in the furnace as an ideal gas; the representative frequency is the centroid frequency of the acoustic noise spectrum; and the empirical relationship includes the transformation of the operating parameter into an effective acoustic noise wavelength.

Abstract: An electronic chef's fork is provided which displays indicia such as food type and degree of doneness for a selected food type and temperature and which includes control areas by which the user of the electronic chef's fork selects the meat type. The operational circuitry of the device allows the user to select among an array of food type options and to thereby designate a degree of doneness for the selected type of food. A prompt message is provided to indicate the degree of doneness attained for the selected food type when the device is inserted into the food.

Abstract: A quartz crystal resonator is excited in two different modes at the same time such that the mass change and the temperature change can be measured independently. In using such a quartz crystal the change in mass can be calculated accurately and in real time, independent of temperature effects.

Abstract: A detector unit of a thermometer of this invention is comprised of a pair of oscillators which are closely installed each other. We make a latch signal of a counter circuit for specially made crystal resonator whose number of proper vibration changes with temperature, and latch a counter value of a counter circuit for reference crystal resonator by said latch signal. We calculate the temperature by a microcomputer using the latched value from the said reference crystal resonator. The power consumption of an electric circuit of the detector unit is less than 0.6 mW under the condition of the supply voltage at DC 2.5V.

Abstract: An apparatus for measuring the temperature of a flowing fluid in a pipe. The apparatus includes a mechanism for actively testing the flowing fluid with acoustic energy and producing a test signal corresponding to the temperature of the fluid. The testing mechanism is disposed on the outside of the pipe and acoustic energy follows a path through the pipe wall. Additionally, the apparatus includes a signal processing mechanism for determining the temperature of the fluid based on the test signal. The testing mechanism is in communication with the signal processing mechanism.

Abstract: A passive sensor system utilizing ultrasonic energy is disclosed. The passive sensor system includes at least one ultrasonically vibratable sensor and an ultrasonic activation and detection system. The sensor has at least one vibration frequency which is a function of a physical variable to be sensed. The ultrasonic activation and detection system excites the sensor and detects the vibration frequency from which it determines a value of the physical variable. The sensor includes a housing, a membrane which is attached to the housing and which is responsive to the physical variable, a vibratable beam attached to the housing at one end and a coupler, attached to the membrane and to a small portion of the vibratable beam, which bends the vibratable beam in response to movement of the membrane.

Abstract: A quartz oscillator temperature sensor which measures temperature based on the change in resonance or oscillation frequency of a quartz oscillator with the change in temperature the oscillator can be constructed by cutting a piece of quartz from a wafer with a thickness of about 80 to 150 .mu.m by rotating the plane of the crystal defined by the electrical and mechanical axes 15.degree. to 25.degree. about the electrical axis and then forming the wafer into a quartz tuning fork. The tuning fork is housed in a case sealed with a stem and coupled to electrical leads with heat resistent solder formed with more than about 90 wt % Pb and less than 10% Sn. The area within the case should be at a substantially high vacuum.

Abstract: A device for estimating a temperature of a working oil in a shock absorber in a suspension system which connects a sprung member and an unsprung member of a motor vehicle, wherein the temperature of the oil is estimated on the basis of at least detected vertical acceleration of the sprung member. The device may be suitably incorporated in an apparatus for controlling the damping characteristic of the shock absorber, wherein an actuator is operated by a controller for changing the damping characteristic, and the controller includes the temperature estimating device, and a device for inhibiting an operation of the actuator to control the damping characteristic when the oil temperature estimated by the temperature estimating device is lower than a predetermined threshold.

Abstract: A noncontact pyroelectric infrared detector is described. A pyroelectric film that also has piezoelectric properties is held in place so that it is free to vibrate. It is electrically stimulated to vibrate at a resonance frequency. The vibrating film forms part of a balanced bridge circuit. As thermal radiation impinges on the film the pyroelectric effect causes the resonance frequency to change, thereby unbalancing the bridge circuit. A differential amplifier tracks the change in voltage across the bridge. The resulting voltage signal is further processed by a bandpass filter and a precision rectifier. The device allows for DC or static temperature measurements without the use of a mechanical chopping device.

Abstract: In a process for finding the value of parameters which change the resonance frequencies of microstructures wherein the microstructures include at least one membrane mounted at its periphery and wherein at least one resonance frequency of the microstructures is between 100 kHz and 100 MHz, the frequency of the characteristic resonance frequency of the microstructures is detected by exposing the microstructures to ultrasound and measuring the intensity of the ultrasound transmitted through, or reflected from, the microstructure and the value of the parameter is then determined by means of a calibration curve.

Abstract: A combined transducer that measures force or displacement and temperature utilizes a pair of vibrating tines to provide a simultaneous output representative of temperature and force or displacement whereby the sum or average of the vibrating frequencies of the two tines is representative of temperature and the difference is representative of force or displacement.

Abstract: An optical interferometer comprises a multi-mode sapphire fiber as a high temperature sensor. One end of the sapphire fiber is coupled to a silica fiber and, in turn, to the sapphire fiber. The sapphire fiber sensor produces reference and sensor reflections that produce optical fringes at the output of a detector coupled to the silica optical fiber via an opto-coupler. The optical fringes are related to displacements of the sensor which, in turn, can provide an indirect measurement of pressure, strain or temperature of the surface.

Abstract: A method and apparatus for non-destructively or non-invasively measuring a temperature change in the inside of a subject, in particular a living subject, identify the temperature change in a region of interest during the course of producing ultrasound images of the region by determining the change of the acoustic impedance of the region of interest, and allocating a temperature change to the impedance change. An installation for treating a living subject with heating radiation which employs the above method and apparatus for measuring the temperature change of a region of treatment, is also disclosed.

Abstract: For surface acoustic wave devices temperature-compensated piezoelectric crystal elements with one or more planar faces are used. An improvement in temperature stability may be expected if the crystal element is made from GaPO.sub.4 and the planar face is defined by Euler angles .lambda. in the range of 0.degree., .mu. in the range of 40.degree. to 75.degree., i.e. preferably 50.degree. to 60.degree., and .theta. in the range of 0.degree..

Abstract: A temperature measuring apparatus measures the temperature of a medium according to the propagation time of ultrasonic waves propagated for a predetermined distance through the medium. The apparatus has a transmitter 11, 12 for transmitting ultrasonic waves having a fixed frequency at predetermined timing and a receiver 13, 14, 15 for receiving the ultrasonic waves and providing a received signal. A delay time detector 24 detects, in response to the received signal, a delay time between the transmission and reception of the ultrasonic waves and a wave number calculator 21 calculates an integral wave number according to the delay time and a period of the ultrasonic waves. A phase difference detector 25 detects a phase difference between the transmitted and received ultrasonic waves modulating the received signal with a frequency that is sufficiently higher than the frequency of the ultrasonic waves.

Abstract: The invention concerns a method and an apparatus for measuring the temperature of an electrically conductive material, said method being based on the measurement of the thermal noise of the material. In the method, the fluctuation of the magnetic field generated by the random motion of the charge carriers in the conductive material is measured using a resonant circuit (3) without contact with the material (1) under measurement. The apparatus comprises a sensor (5) provided with a resonant circuit (3), the reactance element of which is placed at a distance (s) from the material (1) whose temperature is to be measured, and a preamplifier (2), said sensor (5) being mounted inside a frame (20) made of a conductive material, such as copper.

Abstract: The transit time of acoustic waves between a generator and a receiver positioned across a fluid chamber is determined by generating acoustic waves using a self-purging pneumatic sound generator, a transducer adjacent the outlet of the sound generator, and a receiving transducer positioned away from the sound generator outlet so that the acoustic waves received by the receiving transducer pass through a portion of the fluid. The electrical signals generated by the transmitting transducer and the receiving transducer are processed to obtain the impulse response of these electrical signals, and the point of maximum value is determined. This point of maximum value corresponds to the arrival time of the acoustic waves at the receiving location. The transit time determination may be used to calculate the fluid temperature or other parameters.

Abstract: An apparatus and method for sensing temperature in an oil or gas well use an AC-cut temperature crystal connected to a Z-cut crystalline member contained in a crystalline housing that can be subjected to high pressures and temperatures.

Abstract: A sensor is provided which is sensitive to a particular property of a medium and which is thermally activated when in contact with the property containing medium. The sensor is externally mounted on the undersurface of a silicon wafer, the upper surface of which contains a well in which a vibratile bridge element is located. The top of the well is closed off so that the vibratile bridge element is within a chamber. Excitation energy from a source is delivered to the vibratile bridge element to establish vibratory motion which is monitored and detected by a circuit. Presence of the particular property in the medium causes a thermal change in the wafer resulting in a change in the resonance frequency of the vibratory motion of the vibratile bridge element. The frequency shift is a measure of the particular property.

Abstract: A method and apparatus for measuring the internal temperature of a work piece comprises an excitation laser for generating laser pulses which are directed through a water cooled probe, and in an optical fiber, to a first surface of the work piece. The laser is of sufficient intensity to ablate the surface of the work piece, producing a displacement and a resulting ultrasonic pulse which propagates within the thickness of the work piece to an opposite surface. The ultrasonic pulse is reflected from the opposite surface and returns to the first surface to create a second displacement. A second continuous laser also shines its light through an optical fiber in the probe into the first surface and is used in conjunction with signal processing equipment to measure the time between the first and second displacements.

Abstract: A temperature compensated oscillator and a temperature detector have a temperature sensor having a single case in which a pair of AT cut crystal resonator having substantially the same natural oscillation frequency and different cut angles from each other are accommodated. The crystal resonators each constitutes the resonance circuit of respective one of two oscillation circuits. A difference in frequency between the output frequencies of the oscillation circuits is representative of a detected temperature.

Abstract: A vibrating crystal transducer for measuring temperature is disclosed. The crystal includes a single elongated vibrating beam that has a torsional mode resonant frequency that is a function of the temperature of the crystal. The torsional moments of the crystal are reverse symmetric with respect to a nodal line on the beam. The beam is contained in a frame that is secured to a sensor frame member. The beam is attached to the frame by a pair of opposed mounting posts that are in line with the nodal line on the beam. The beam, the beam frame (16) and the mounting posts are formed out of an integral section of crystalline material. When the beam is vibrated, the reverse symmetrically opposed torsional moments along the beam cancel each other out and, consequently, no torsional energy is transmitted through the mounting posts to the beam frame or the sensor frame.

Abstract: The temperature of a quartz crystal oscillator is determined by comparison of a pair of inharmonically related overtone oxcillations of the same vibrational type, e.g. a thickness shear mode, and of the same overtone order. The use of inharmonically related signals relaxes the contraints on crystal design. The technique may be employed in a crystal controlled frequency synthesizer to provide a feedback signal for maintaining constant output frequency.

Abstract: A process and apparatus for the photothermal and/or calorimetric investigation of gaseous, liquid and solid measuring material is based on the detuning of an ultrasonic resonator (1). The latter has an ultrasonic transmitter (2) and an ultrasonic receiver (3), which face one another. The signal from the receiver is analyzed by an analyzer (5) as to its amplitude or phase position which gives, as a result of the temperature dependence of the sonic velocity, information on thermal changes in the ultrasonic resonator designed as a gas cell or calorimeter. The present apparatus makes it possible to detect gases or to calorimetrically investigate the material to be investigated, particularly light-conducting elements (5), such as light fibers.

Abstract: A vibrating crystal transducer for measuring temperature including a bonding area from which three or more tines extend. The tines have a torsional mode resonant frequency that is a function of temperature. Electrodes on the transducer excite the tines into vibration so that the torsional moments of the adjacent edges of the adjacent tines are reverse symmetric. When the tines are vibrated, the reverse symmetrical vibrational moments of the individual tines cancel so that there is no torsional moment, or twisting, within the area between the points where the tines intersect, which is the area defined by the bonding area. Since the bonding area does not serve as a sink for torsional energy, torsional energy is not lost through the bonding area so that the transducer has a relatively high quality factor and torsional vibration of the transducer cannot cause the transducer to eventually work loose of a mounting pad to which it is attached.

Abstract: A gas thermometer has a case with a case end section (10) made of metal of good thermal conductivity and a main case section (14) made of material of poor thermal conductivity. By means of separating walls (46, 48, 62, 64, 70) and reflector walls (66, 68), two sound paths are created in the interior of the thermometer case, which differ by twice the distance between the reflector walls (66, 68). The phase difference of partial sound wave fields which are obtained by splitting a sound wave field produced by a common sound generator (40) between the two paths is converted to an electrical signal corresponding to the temperature in the case end section (10) by using microphones (26, 28) and an analyzing circuit (92) connected with them.

Abstract: An ultrasonic distributed temperature sensor comprises an elongate ultrasonic waveguide in the form of steel or nickel wire 0.16 cm in diameter and up to 10 meters long, which is strung around the area whose temperature is to be monitored, eg an aircraft engine. The wire is provided with discontinuities in the form of annuli welded on to it to form annular flanges, which serve to partially reflect ultrasonic pules launched into one end of the wire. These flanges, known as "posi-notches", divide the waveguide, and thus the area to be monitored, into a number of zones, the size of each zone being determined by the spacing of the adjacent flanges defining it. In operation, the temporal spacing of each pair of successive partially reflected pulses is a measure of the average temperature of the zone defined by the flanges producing that pair of pulses.

Abstract: A technique for measuring the unknown subsurface temperature T.sub.s of a bulk transparent medium such as ocean water by splitting a pulsed laser beam having a high intensity into two sub-beams, one of which is a probe beam directed into the medium. The intensity of the output beam pulses exceeds a predetermined threshold sufficient to cause stimulated Brillouin scattering within the medium and to produce therefrom a phase-conjugate beam which propagates along the path of the first sub-beam but in the opposite direction. The second sub-beam combines with the PC beam and the combined beams mix at the cathode of a photodetector thereby producing a heterodyne frequency proportional to the temperature T.sub.s. Converts the heterodyne frequency into a temperature value yields the desired unknown T.sub.s.

Abstract: A technique for measuring the unknown subsurface temperature T.sub.s of a bulk transparent medium such as ocean water by generating a continuous (cw) laser beam and pulsed laser beam both having the same wavelength, with the intensity of the pulsed laser beam exceeding the intensity required to produce stimulated Brillouin scattering in the water. By directing the pulsed laser beam into the water, it causes a return phase-conjugate beam to emanate therefrom. The return phase-conjugate beam and the pulsed laser beam are separated, and the phase-conjugate beam and the cw beam are mixed together thereby producing a heterodyne frequency proportional to the temperature T.sub.s. By converting the heterodyne frequency into a temperature value, yields the desired unknown T.sub.s.

Abstract: A temperature measurement device is provided with a temperature sensing element which contains a quartz resonator having a quartz oscillating crystal whose ratio of width to thickness is in the range of 9.48 to 9.69, and an antenna which receives stimulus for the quartz oscillating crystal and transmits waves of reverberatory oscillation. The temperature measurement device is capable of measuring temperatures in the range of normal room temperature to extremely low temperatures (4.degree. K.).

Abstract: In a fire monitoring system for monitoring the occurrence of a fire in which a space to be monitored is imaginarily subdivided into plural subspaces so that plural channels passing through the subspaces are set so as to intersect to each other in a lattice form. The propagation speed of ultrasonic waves propagating through each of the channels is measured, on the basis of which the propagation speed of the ultrasonic waves in each of the subspaces is calculated in the same manner as the solution for each element of a matrix is obtained, and then the temperature in each of the subspaces is obtained. By providing the system with a humidity sensor, the temperature for a dry condition is obtained.

Abstract: The principal surfaces of an oscillator quartz crystal body for a temperature sensor oscillator are plane, parallel and of substantially the same size and are oriented with respect to the usual x-y-z coordinate system of electric, mechanical and optic axes so that the angle .phi. of the electric (x) axis with respect to either of these planes lies within a tolerance range extending from +1.degree. to -1.degree., while the angle .theta. of the optic (z) axis with respect to either of these plane lies either in the 3.degree.-6.degree. range or in the 68.degree.-72.degree. range. Since in the regions of .theta.=4.degree. and .theta.=70.degree. the change of the temperature coefficient with variation of the angle .theta.

Abstract: A method and apparatus for measuring temperature at different localized zones within a fluid medium, for example parts of the tops of fuel sub-assemblies in a reactor core, in which a continuous stress wave signal is transmitted from a remote location to targets at the zones, the frequency of the transmitted signal is progressively changed, waves reflected from the targets are received and multiplied with a reference signal, whose frequency changes at the same rate as the transmitted signal, to produce output signals wich are analyzed to derive values for the temperatures at points between the targets. A transmitter 10, target 12, receiver 14 are arranged so that oscillator 24 sweeps the transmitted signal and provides the reference signal to detector 28 which multiplies the received and reference signals and the beat frequency output signals from different targets are fed to a computer 38 for analysis.

Abstract: An electronic thermometer has an oscillator, the frequency determining element of which is a temperature sensitive piezoelectric element (2), used as a measuring sensor, which is located inside a sealed housing (3). The piezoelectric element is provided with two termial electrodes (4, 5) which are galvanically separated from the oscillator circuit bia an inductively coupled pair of coils (6, 7); the coil (6) connected to the terminal electrodes is tightly encompassed by the housing. An evaluation unit (10) for detecting the temperature is connected to the oscillator circuit.

Abstract: A circuit is shown for representing the internal temperature of a crystal, through a combination of certain harmonic frequencies excited in that crystal. By forming a signal which is equal to nF.sub.A -F.sub.B, i.e., n times a lower harmonic frequency minus F.sub.B, an nth harmonic frequency, or F.sub.A -1/n F.sub.B, e.g., it is possible to have a signal which is near linearly dependent upon temperature which can be used in representing same. This composite signal is also seen to be highly sensitive to temperature changes yielding an improved thermometric system as compared to conventional systems.

Abstract: The subsurface temperature of a body of water such as an ocean is measured remotely by directing a laser beam deeply into the water and analyzing the resultant Brillouin and Rayleigh backscatter components. Wavelength shifted Brillouin scatter is mixed with the unshifted Rayleigh scatter in a self-heterodyne manner for each volume element of illuminated water and the frequency of the heterodyne signal is measured. This produces the desired temperature-depth profile of the water.

Abstract: Subsurface waves in a body of water such as an ocean caused by a submarine are remotely nonacoustically detected by monitoring subsurface water temperatures using a laser. A pulsed laser beam is directed into the water to at least the depth of the thermocline and an analysis is made of the resultant Brillouin and Rayleigh backscatter components. Wavelength shifted Brillouin scatter is mixed with the unshifted Rayleigh scatter in a self-heterodyne manner for each volume element of illuminated water, and the frequency of the heterodyne signal is measured and converted into temperature. This produces the desired temperature-depth profile of the water enabling detection of internal waves generated by submarines.

Abstract: Integral temperature measurement in electrical machines, transformers and energy conversion systems. An integral temperature measurement for electrical machines, transformers and energy conversion systems produces no additonal potential or voltage in the windings of such equipment. As a result, no conductive or semiconductive material can be used in a temperature sensor. The present invention utilizes the temperature dependency of the propagation conditions of sound or ultrasound in gases and also makes use of light waveguide technology. The sound or ultrasound is guided in a flexible capillary along a path along which an integral temperature measurement is to be taken.

Abstract: An electronic thermometer has an oscillator, the frequency determining element of which is a temperature sensitive piezoelectric element, used as a measuring sensor, which is located in a sealed housing of electrically insulating material. The piezoelectric element is provided with two terminal electrodes, which are each connected via a respective capacitor to the oscillator circuit, and each of the two capacitors has electrodes, one located inside and one located outside the housing.

Abstract: An apparatus and method for measuring high temperatures in a boiler transmits pulses of acoustic waves, from one side wall of the boiler to an opposite side wall thereof. Acoustic noise within the boiler, as well as the transmitted pulses of acoustic waves are received at the opposite side of the boiler. The received signal is digitized and compared to a digitized sample of the pulses during a time period which is more than the maximum transit time for the pulses between the side walls. A point of maximum correlation between the sample and the signal is taken as the arrival time for the pulse and is used to calculate the transit time of the pulse across the boiler. This transit time is used in turn to calculate the velocity of the pulses. The temperature can then be calculated as a function of the velocity, the molecular weight of the medium and the specific heat ratio of the medium. Each pulse has a modulated frequency between 500 and 3,000 Hz.

Abstract: Temperature measurement is effectively carried out by converting pulses derived from a pulse generator, in which the pulse gaps change as a result of a measured condition, for example temperature, by converting electrical pulses received from the pulse generator into light pulses, and then evaluating the light pulses with respect to a clock rate in a counter (22). The light pulses can readily be transmitted via a light pickup (9b) and fiber optic or the like (9a) to a remote evaluation unit. Preferably, the light is generated by a light emitting diode or a laser diode (8'), serially connected with a switching transistor (13') and energized upon receipt of a pulse from the pulse generator. The arrangement permits use of a piezoelectric element (2) such as a frequency determining quartz to control the frequency of an oscillator, the frequency of which is then converted into the pulses with the respective pulse gaps.

Abstract: A temperature measuring device comprises a ring oscillator having a nominal oscillating frequency positioned at a location where temperature is to be measured. The ring oscillator emits electromagnetic radiation to an antenna located at a convenient distance from the ring oscillator. The antenna transforms the electromagnetic radiation into an electrical signal. A receiver receives the electrical signal and measures the frequency of the electrical signal to determine the corresponding temperature. The temperature may then be visually monitored from a display or electronically monitored by other devices.