Abstract: The disclosed apparatus and method diagnose deterioration of a steel-reinforced concrete smokestack by taking its infrared ray photograph, thermographically processing the photograph into an outside surface temperature distribution diagram so as to detect a defect as a singular point on the diagram, measuring the circumferential length (L) of the defect from the diagram, finding concrete crack width (W) at the defect based on outside surface temperature difference between sound portion of the smokestack and the defect, and calculating reduction of the strength of the smokestack wall structure due to the defect by using the circumferential length (L) and the concrete crack width (W) of the defect.

Abstract: Apparatus is provided for investigating surface structures irrespective of the materials involved. A fine scanning tip is heated to a steady state temperature at a location remote from the structure to be investigated. Thereupon, the scanning tip is moved to a position proximate to, but spaced from the structure. At the proximate position, the temperature variation from the steady state temperature is detected. The scanning tip is scanned across the surface sturcture with the aforesaid temperature variation maintained constant. Piezo electric drivers move the scanning tip both transversely of, and parallel to, the surface structure. Feedback control assures the proper transverse positioning of the scanning tip and voltages thereby generated replicate the surface structure to be investigated.

Abstract: A radiant-energy temperature measuring apparatus of a scanning type having a linear array of light-sensitive elements which generate photoelectric signals corresponding to respective amounts of radiant energy produced at different points of an object and vicinities thereof on a straight line corresponding to the above linear array, and further having a device for determining a temperature of the object at desired one of its different points, based on the photoelectric signal generated by one of the light-sensitive elements which optically matches the desired one point of the object. The apparatus includes an edge detector for detecting an edge of the object, based on the photoelectric signals generated by the light-sensitive elements, and a selector for selecting the desired one point of the object, by designating a number of the light-sensitive elements as counted from the element corresponding to the detected edge of the object, to the element which corresponds to the above-indicated desired one point.

Abstract: A technique for generating isotherms representing the cross-sectional temperature profiles of molten glass flowing in a forehearth channel. A plurality of temperature sensors are placed at predetermined locations within the plane of the channel cross-section, advantageously in a rectangular grid, to provide a matrix of temperature readings. Digitalized temperature readings from these sensors are routed to a processor, which interpolates these temperature readings to approximate the temperatures intermediate the various sensing points, and optionally beyond the array of sensing points. The isotherms are obtained by fitting a Lagrangian interpolating polynomial through the various recorded temperatures. The interpolated values thus generated may be used to provide real time displays of isotherms in the forehearth cross-section under examination, or may be included in a control loop.

Abstract: A method and apparatus for the non-destructive identification of coated and uncoated metal parts employing infrared thermography. The apparatus comprises a means for directing infrared radiation onto the surface of a part; a means for scanning the part surface for reflected infrared radiation; a means for capturing the reflected radiation and converting it into a signal representative of variations in radiation reflected from the surface of the part; means for etching an identifying code into the surface of the part; and means for displaying the signal as a video image. The method comprises altering the surface reflective characteristics of a part to produce an identifying code, irradiating the part with infrared radiation of a specific wavelength and detecting differences in the amount and intensity of radiation reflected from the part.

Abstract: Defects in varistors are detected by pulsing a high current through the varistors and shortly thereafter mapping the temperature distribution of a main varistor surface by heat sensitive equipment. The presence of a localized hot spot sufficiently higher in temperature than a reference temperature level in the varistor indicates the presence of a defect. The disclosed technique is especially adapted for detecting defects that manifest themselves as incipient hot spots but which quickly disappear from observation because their heat rapidly disperses into surrounding varistor material.

Abstract: A thermopile detector means for a temperature measuring instrument physically and electrically configured to supply an output signal which indicates target temperature substantially independent of the influence of ambient temperature changes. The detector means includes a first thermopile device exposed to radiation from the target and a transducer means, preferably a second thermopile device, shielded from the target and connected in series opposition to the first.

Abstract: An imaging radiometer for high temperature measurements has a sensor head comprised of a solid-state video camera operated in fixed gain mode, preferably one with a charge injection device detector, an infrared filter, and a lens system to image a radiating object on the detector array. Spectral response of the system is limited to 700 to 1100 nanometers or a smaller portion of this near-infrared band. The video signal output of the sensor is processed and object temperature is displayed on a television monitor; alternatively the video signal is presented to a digital frame grabber and converted to a temperature map.

Abstract: The present invention relates to a process for the detection and recording of the weak points or defects on hot semifinished iron and steel industry products, by application of the flame of an oxygen-supplied blowtorch to the surface to be examined, displacing the application point along the surface, picking up the image of the application point by video camera, and transmitting the image to a remote location. An observer viewing this screen can make a map of the surface examined, recording thereon the weak points or defects detected both by their dimensions and by their type. This process finds application in the hot treatment of the slabs, blooms, and steel rods, when the casting, defect repair and rolling operations are to be carried out continuously.

Abstract: A method of measuring the temperature in a high pressure furnace of a hot isostatic pressing apparatus, wherein a closed-end pipe having its inside communicated with the inside of the high pressure furnace and enabling a pressure medium to pass therethrough is disposed in the furnace, an incident top end of an optical fiber, a bundle of optical fibers or like other equivalent optical rod-like memeber is disposed to the open end of the closed-end pipe so as to be capable of receiving thermally radiated light from the inside of the closed-ended pipe and an exit rear end thereof is led out through a cover and to the outside of said high pressure vessel and a measuring system is connected to said exit rear end to detect heat radiation power from the top end of the closed-end pipe to thereby measure the temperature inside of the furnace.

Abstract: Effective removal of atmospheric contamination for a sequence of satellite olor scanner ocean imagery is achieved through determination of an optimum Angstrom exponent for weighting data in a plurality of channels of different wavelengths by the method of providing a refresh plane display for data from one channel, weighting data from a selected reference channel as determined by an Angstrom exponent, interacting the weighted reference channel data with the data in the plane by subtraction therefrom to reveal atmospheric aersol bands, varying the Angstrom exponent to determine an optimum value at which the aerosol bands become transparent, and then weighting data from each of the channels by use of that optimum value.

Abstract: A method and apparatus for the non-destructive identification and location of subcoating corrosion on a coated metal surface employing infrared thermography. The apparatus comprises a heat source for directing pulsed infrared radiation onto a test surface; a scanner for scanning the test surface for infrared radiation being emitted therefrom; a detector for capturing said emitted radiation and converting it into a signal representative of the thermal characteristics of the surface; and video display apparatus for visually displaying the signal as a thermal map of the surface. The method comprises the steps irradiating a test surface and detecting temperature differentials that occur on the irradiated surface.

Abstract: The tip of an alloy rod in a vacuum chamber is remelted by radiation with an electron beam from an electron gun and the remelted droplets fall into a mold where they solidify. The droplets are scanned a plurality of times through a window provided on the vacuum chamber by an image pickup device as they pass its field of view. From the signal of the maximum level obtained during these scans, temperature data of the droplet is obtained by a temperature measurement control device.

Abstract: A hand held radiation detector may be used for scanning of a surface from a distance to obtain a gross indication of temperature variations in the surface. The radiation detector is provided with a nosepiece having a conical cup therein which can be placed directly against a surface. The radiation sensor views the surface through the cup to obtain an accurate indication of temperature substantially independent of the emissivity of the surface. The radiation sensor and a temperature sensor are potted with high conductivity material in an insulating sleeve within the nosepiece. The nosepiece is of high conductivity material and is thermally connected to a main housing which serves as a heat sink. Temperature indications are obtained from the sensed radiation indication by means of a piecewise linear gain analog circuit.

Abstract: A portable temperature data recorder for temporarily storing plural sets of temperature data representative of temperatures at a single location or at different locations, and automatically transferring the stored temperature data to a data processing unit. The portable recorder has a connector for connection thereof to the data processing unit. The portable recorder may further have a connector for connection thereof to a stationary temperature detector or thermometer installed at each measurement location. Alternatively, the temperature recorder incorporate a temperature detector for measuring the temperatures at the measurement locations. A clock circuit may be provided in the portable recorder, so that the temperature data may be stored together with measurement time data. The temperature detector may be a radiation thermometer provided at the measurement location, or built in the portable recorder.

Abstract: Hand-held instrument for measuring the temperature of a target without contact with the target. The instrument utilizes a microprocessor and a digital display to calculate and indicate different temperature functions. Compensation is included for the effects of emissivity and ambient temperature changes which otherwise could result in inaccurate readings. Temperature trend direction liquid crystal arrow(s) actuated by the microprocessor are included in the display.

Abstract: In the present invention, a discrete region of the TBC is heated, as by applying a controlled quantity of laser energy onto the region for a time interval. Then, the radiant thermal energy of a region outside the laser strike region is measured at a predetermined time following the termination of the laser pulse. The intensity of this measured radiant energy is then compared with the radiant intensities which have been experimentally obtained from known thickness specimens and the thickness is inferred therefrom.

Abstract: A method and apparatus for simulating thermal images of various target dees and backgrounds as they would appear when viewed with a thermal viewer. A number of test elements of varying thicknesses are arranged in such a manner that upon solar heating the thermal signature thereof will represent the particular target for which the elements have been arranged, thereby eliminating the need for having to physically pursue the acquisition of the actual target for test purposes.

Abstract: A hand held radiation detector is adapted for scanning the subject while a bar graph at one end of the detector is observed. The field of view of the radiation detector is variable by means of removable lens assemblies which have Fresnel lenses positioned at the focal lengths of the lenses from the radiation sensor. The lens assemblies are matched to provide the same flux density to the radiation sensor independent of the field of view. Crosshairs provided on the rear of a lens support assist in aiming the radiation detector. The time constant of the display is varied with the sensitivity of the display.

Abstract: Method and apparatus for detection and selective after-quenching of red hot pockets in previously quenched hot coke lying on a coke bench, in which the temperature of the coke is sensed and recorded over the entire surface or area of the coke bench by temperature sensors installed thereabove, and if excessively hot coke portions or local areas are found, only those excessively hot coke portions are acted upon for after-quenching automatically in controlled manner with a focused water jet or spray using only a minimum amount of water for as short a time as possible.

Abstract: A satellite method for measuring sea surface temperature uses simultaneous overage by two satellites in the same spectral window plus a simplified atmospheric radiative transfer model. A geostationary satellite and any polar orbiting satellite provide nearly coincident infrared imagery of a given area with points of equal and unequal observation angles. The calibration curve of the data for one satellite is adjusted to match the temperatures of the better calibrated satellite data along the equal angle points. A difference image is obtained from the resulting two satellite temperature images. The difference image together with the two observation angles and the temperature of the more accurate satellite radiometer are input to a suitable atmospheric model to obtain sea surface temperature at each point in the study area. The result is an accurate sea surface temperature for each point within a given area which is corrected for a spatially variant atmosphere.

Abstract: The present invention relates to a procedure and a device for determination of the temperature of an object by measurement of electromagnetic radiation emitted by this object. A portion of the radiation emitted by the object of measurement is transmitted by a transmission device to a wavelength dividing device.The wavelength dividing device causes a portion of the spectrum of the radiation corresponding to the spectral sensitivity range of the detector or pair of detectors to be distributed across the radiation-sensitive surface of the detector or pair of detectors. The detector senses the position of the center of gravity of the illuminated spectrum which is converted by the signal processing unit to temperature information, and displayed by an output device.Using a sole position-sensitive detector, the relative magnitude of two currents I.sub.1 and I.sub.2 indicates the position of the center of gravity.

Abstract: A photothermal deflection detector for thin layer chromatography includes a translation means for holding and moving a thin layer chromatographic plate; a first impinging laser beam (e.g., 20 mW chopped argon laser) focused on the moveable thin layer chromatographic plate; a second probing laser beam (e.g., 2 mW He-Ne laser) intersecting the impinging laser beam directly above and parallel to the moveable thin layer chromatographic plate; and a laser deflection measuring means (e.g., knife edge, photodiode detector and lock-in amplifier demodulator) responsive to the thermal lens effect created by the absorption of the impinging laser beam by the separated compounds on the thin layer chromatographic plate. Such a system when applied to separated compounds (e.g., 1,2-napthaquinone, phenanthrenequinone and .alpha.-ionone) exhibits detection limits that range from 30 ng to 7.5 pg, depending upon the compounds's ability to absorb the impinging light.

Abstract: A radiation detector includes a flat housing 14 having a radiation sensor 16 at one end thereof and a bar graph display 18 at the other end thereof. The bar graph display provides an indication of radiation sensed from a limited surface area as the sensor is scanned across an extended surface area. The width of the housing 14 is such that, when the housing is held at about arm's length in the line of sight, the width defines a field of view which approximates the field of view of the radiation sensor.

Abstract: A method for the structural, superficial and deep analysis of a body is disclosed. The method includes scanning the body to be examined using a modulated excitation radiation beam so as to impart a thermal modulation to the body. The thermal modulation is then measured on the side of the body distal to the side exposed to the beam. The amplitude as well as the phase of the measured thermal modulation is used to determine the thickness and structure of the body. A device for accomplishing the above described method is also disclosed.

Abstract: An apparatus is described which is capable of producing an image of a smelt bed of inorganic chemicals collected at the bottom of a kraft pulp recovery boiler. The image produced is free of interferences of fume particles and gaseous radiation which have obscured prior attempts to view hot surfaces under such environmental conditions. The apparatus includes an industrial closed circuit video camera fitted with an infrared imaging detector or vidicon tube. An objective lens obtains the image. An optical filter interposed between the lens and the vidicon is a key element of the invention and is selected to reject radiation less than about a micrometer to avoid fume interference. The filter is further selected to reject all but limited ranges of radiation to avoid gaseous species overlying the smelt bed which are strongly emitting and absorbing. As an example, a spectral filter centered at 1.68 micrometers with a band width of 0.07 micrometer is suitable for imaging a kraft recovery smelt bed.

Abstract: A camera contains a row of diodes sensitive to infrared radiation and mounted on a turntable for rotation about the optical axis of the camera. The signals from the diodes provide a temperature profile of a band across the width of a strip of hot rolled steel moving in a direction orthogonal to the optical axis and to the length of the row of diodes. Since the diodes are low accuracy devices, their measurements are compensated by normalizing co-efficients derived by comparison with the signal provided by an optical pyrometer viewing the central part of the steel strip in the region of the optical axis. To enable all diodes to be calibrated, calibration is effected with the turntable rotated 90.degree. to align all the diodes with the central part of the strip as viewed by the pyrometer. The camera may be mounted on one arm of a C-frame having X-ray tubes in an arm and X-ray detectors in the other arm for the purpose of measuring the thickness profile of the strip in known way.

Abstract: A sighting system primarily for use with infrared thermometers and that provides a visible light beam, the geometry of which is congruent with the field of view of the infrared optics of the thermometer to provide the user with an accurate representation of the intersection of the field of view cross-section of the object of which the temperature is being measured by the thermometer. Two novel embodiments are disclosed, one of which utilizes Fresnel lenses and one of which utilizes a Cassegrainian lens system. Both embodiments provide means for accommodating an isolated visible light source and passage of the visible light generated therefrom through the identical lens system used by the infrared detector to develop the signal indicative of the infrared energy and therefore temperature generated by the object to which the infrared thermometer is directed.

Abstract: The present invention provides a thermal imaging method to evaluate the surface and subsurface properties of a material and is based on techniques of optical beam deflection thermal imaging. The invention uses a localized excitation source, such as an optical beam, to provide localized heating of the sample surface. A surface thermal gradient is induced on the sample surface as heat flows, in three dimensions, from the area of localized excitation into the test material. The surface temperature gradient causes a thermal refractive lens to be generated in the fluid (gas or liquid) adjacent to the sample surface. An optical probe beam is directed through the thermal lens and is deflected by changes in a refractive index of the thermal lens. Changes in the refractive index are induced by variations of the surface temperature. In this manner, a detailed surface temperature profile can be generated which reveals surface and subsurface properties of the material tested.

Abstract: A portable, battery operated noncontact temperature measuring device including a lens for collecting infrared radiation and a thermopile for producing a signal indicative of the intensity thereof. The thermopile signal is amplified, linearized and summed with an ambient temperature signal derived from a temperature responsive element, e.g. a diode chip mounted immediately adjacent a cold junction of the thermopile. The resulting composite temperature signal is then processed and displayed. The ambient temperature signal is also utilized to control the impedance of a dual field effect transistor, which in turn controls the gain of the amplifier. Thus, temperature induced variations in the responsivity of the thermopile are compensated by corresponding changes in the gain of the amplifier.

Abstract: Apparatus for measuring the temperature distribution along the inside walls of narrow, shaft-shaped spaces such as heating flues of coking and similar ovens using a radiation pyrometer with an evaluating arrangement, whereby a radiation optical system is disposed at one of the ends of the space and contains a mirror tiltable about an axis, for optical coverage of the entire length of the space and forwarding of the detected radiation into the path of rays to be evaluated, as well as a positioning arrangement for tilting the mirror over the area to be optically covered. Therewith a fixed mirror is arranged after the tilting mirror and the path of rays to be evaluated is focused to the end of a photoconductor, which, in a transportable and coolable measuring lance, is directed to an evaluating arrangement. The measuring lance can be coarsely and finely positioned by means of a carriage arrangement.

Abstract: A temperature scanner for use in a hot strip rolling mill to enable ready determination and analysis of the temperature distribution over a hot strip of material passing through the mill. The temperature scanner comprises a photocell scanner unit 1, situated over and scanning a strip 2 perpendicular to its direction of travel, electronic analyzer 6 connected to the scanner unit via lead 5 and displayer 7 connected to the analyzer 6 by lead 8. The analyzer 6 compares the temperatures detected with a reference level set and together with the displayer 7 displays a map of the strip surface in which areas at temperature above the reference level are distinguished from those below the reference level. Alternatively, one or more temperature profiles corresponding to one or more scans of the surface are displayed, in which temperatures above the reference level are distinguished from those below the reference level.

Abstract: A surface temperature measuring apparatus is arranged to comprise means for conducting a first radiant energy generated from an object to be measured, said energy conducting means being provided opposite to said object, and reference radiation source means provided to mask the influence of radiation noise from the furnace on a radiometer and to generate a second radiation whose level is substantially determinable, whereby the surface temperature of said object can be determined from the detected values of said first and second radiations.

Abstract: An infrared thermometer primarily for agricultural applications utilizes an additional infrared sensor oriented for detection of sky radiation to compensate for reflection of sky radiation from the plant or other object to which the thermometer is directed. Preferably implemented in a gunlike, hand-held instrument, the invention utilizes a potentiometer for adjusting the signal level derived from a wide-angle, sky-directed sensor to account for changes in plant reflectivity characteristics. The adjusted signal is then summed with the signal derived from the conventional object-directed sensor to produce a composite signal which is applied to a meter-like device for display of object temperature with improved accuracy.

Abstract: A method for the remote testing of spray nozzles on headers in a nuclear reactor containment building to determine whether the nozzles are open or blocked. Heated air under pressure is supplied to the headers, and an open nozzle reaches a higher temperature than a blocked nozzle. The headers and nozzles are scanned by an infrared camera having a thermogram display, and open nozzles appear in the thermogram as extending from the headers whereas blocked nozzles appear as minor protrusions on the headers. The camera is mounted on a polar crane within the building, the crane having an axis of rotation which coincides with the axes of the headers and the camera being displaced from the crane axis, and the crane is rotated around its axis during the scanning of the headers and nozzles by the camera.

Abstract: The invention relates to a thermographic apparatus intended in particular for diagnosing disturbances in circulation in the extremities of a patient, by recording the temperature distribution along a selected line extending from the ankle of a patient up to the thigh on both legs of the patient, whereafter any asymmetry in the two registered temperature profiles is used for the basis of a diagnosis. The apparatus comprises a temperature transducer (4), preferably an IR-detector, which is carried on one end of an extendable and retractable arm (6), so that the transducer can be moved manually along a selected line on the leg (2) of the patient. Coupled to the arm (6) is a position transducer (11) for generating an electric signal representative of the distance moved by the temperature transducer. The apparatus also includes a recorder (10) to which both the temperature signal and the position signal are transmitted and which is arranged to record the measured temperature profile simultaneously.

Abstract: A temperature pattern measuring device for obtaining the surface temperature distribution of an object. The device receives an image of the measured object and two different wavelength components of light emitted from the object. The device performs a two color temperature process for each minute area within a visual field of the image pickup, detecting the temperature at a portion on the surface of the corresponding measured object, thereby obtaining the temperature pattern thereof. The above minute areas can be set by an electrical method using photoelectric conversion means. Also, a supervision unit for the weld zone at an electrically seamed pipe, may employ the temperature pattern measuring unit of the present invention, the supervision unit producing a composite display of the form of the weld zone and the temperature pattern thereof.

Abstract: An infrared scanner for sensing temperature is presented with the inclusion of a meter providing a digital read-out of the temperature. The scanner utilizes an infrared detector, scanning a field including a reference of known temperature and an object of unknown temperature. The scan is performed by a raster controlled by a horizontal oscillator and a vertical sweep circuit. During the scan, video signals are emitted from a video amplifier, which signals correspond to the temperature of objects within the raster. Delay circuits are provided in interconnection between the video amplifier, horizontal oscillator, and vertical sweep circuit for isolating video signals corresponding to the temperature of the reference and the object. A logarithmic amplifier receives such video signals and produces an output indicative of the temperature of the object as a function of the temperature of the known reference.

Abstract: In a radiation heat loss detector, radiation from an extended surface area is detected with a sensor having a wide field of view closely matching that of an associated camera. By simultaneously photographing the surface area of interest and detecting the radiation from that same area, a clear record is provided for future use. A wide band radiation sensor is used. Compensation for environmental radiation is made by first viewing the environment with the sensor and holding the sensed signal and then subtracting that signal from the flux detected when the sensor faces the extended surface area. The date and time are also recorded on the photograph. A sonar device positioned on the camera provides a distance indication which, with a known field of view, allows for a determination of the total flux from the surface area, a determination of convective heat losses from the surface and a correction for atmospheric absorption of the radiant energy.