Abstract:
A method for measuring furnace temperatures. The method includes obtaining radiance measurements from a plurality of regions of interest (ROIs) using a plurality of thermal imaging cameras, and measuring a surface temperature using a radiance measurement obtained from an ROI selected from the plurality of ROIs. Measuring the surface temperature includes determining an effective background radiance affecting the selected ROI using radiance measurements obtained from ROIs different from the selected ROI, obtaining a compensated radiance by removing the effective background radiance from the radiance measurement obtained from the selected ROI, and converting the compensated radiance to the measured surface temperature.
Abstract:
Methods and apparatus are provided to determine the emissivity, temperature and area of an object. The methods and apparatus are designed such that the emissivity and area of the object may be separately determined as functions dependent upon the temperature of the object derived from a three or more band infrared measurement sensor. As such, the methods and apparatus may only require a regression analysis of the temperature of the object without any regression analysis of the emissivity and area of the object.
Abstract:
A thermal imaging system and method for quantitative thermal mapping of a scene. The system comprises a thermal imaging device, a heat source of known temperature and emissivity located within the scene viewed by the thermal imaging device and a processor adapted to generate a calibrated temperature map of the scene from the data supplied by the thermal imaging device, based on the known temperature of the heat source. This enables accurate temperature measurements to be made using inexpensive uncooled Focal Plane Array detectors.
Abstract:
An apparatus for measuring the temperature of a gasification reactor using an optical pyrometer is disclosed. In one embodiment the apparatus may include a feed injector adapted to receive light conduits. The feed injector (2) includes a feed injector tip (6) having an opening, the feed injector tip being in fluid communication with a feed inlet (8) and a flange connector (4), the flange connector being in optical alignment with the opening of the feed injector tip. A blind flange (10) should be sized to fit on the flange connector of the feed injector and thereby form a gas pressure resistant seal. A pressure sealing gland (12) is fitted in the blind flange such that a light conduit (22a or 22b) can pass through the blind flange and that the receiving end of the light conduit extends into the feed injector such that the light receiving end of the light conduit is in optical alignment with the opening of the feed injector tip. An optical coupler (26a or 26b) functions as an optical connection between the light transmitting end of the light conduit to an fiber optic cable (28a or 28b) and thus to an optical pyrometer.
Abstract:
Apparatus and method for non-contact temperature measurement of a film growing on a substrate which accounts for the change in emissivity due to the change in film thickness. The system employs an adaptively calibrated pyrometer wherein the substrate emittance is continuously computed so that the temperature measurement is accurate regardless of the emittance variation. The new system is easily constructed by adding data processing system software and hardware to conventional pyrometers.
Abstract:
Apparatus for measuring the value of the directional spectral hemispherical reflectance of the surface of a target when not engaging but being spaced from the target employs a hollow elongated member having a longitudinal axis and first and second opposite ends. The area of the first end is relatively large relative to that of the second end. The first end is open. The member has an inner chamber extending between the ends and has an inner surface adapted to reflect light falling within a specified wave band. The member when the apparatus is in use is positioned with the first end adjacent but spaced from a selected portion of the surface of the target. The longitudinal axis is oriented essentially normal to a region on the selected surface which would be engaged by a line coincident with the axis and sufficiently extended outwardly from the first end. A beam of light falling within said band is directed within at least a portion of the chamber along the axis and outward through the first end to impinge upon the selected surface portion. A portion of the beam is reflected after said impingement backward through the first end into the chamber. The reflected light which strikes the inner surface of the chamber is directed backwardly within the chamber toward the second end. An electrical signal derived from at least a portion of the backwardly directed light provides a measurement of said reflectance value.
Abstract:
The present invention is a method and apparatus for calibrating a temperature feedback value in a wafer processing chamber to automatically compensate for variations in infrared emissions from a heated semiconductor wafer due to variations in composition and coatings from wafer to wafer. A calibration wafer with an imbedded thermocouple is used to generate a table relating actual wafer temperatures to power supplied to the heating chamber and infrared emissions detected by a pyrometer. A sample wafer of a batch to be processed is subsequently placed in the chamber at a known power level, and any difference between the detected infrared emission value and the value in the table is used to adjust the entire table according to a first predetermined formula or table. Before each wafer is processed, a known source of infrared light is reflected off the wafer and detected. The reflected light value is compared to a reflection measurement for the sample wafer. The difference in reflection measurements is correlated to emissions from heating, and the calibration table is fine-tuned with the correlation value according to a second predetermined formula or table to account for variations in emissions between individual wafers due to variances in wafer surface conditions.
Abstract:
The present invention teaches a unique laser radiometer capable of accurately measuring the radiation temperature of a radiant surface and independently measuring the surface's emissivity. A narrow-band radiometer is combined with a laser reflectometer to measure concurrently radiance and emissivity of a remote, hot surface. Together, radiance and emissivity yield the true surface temperature of the remote target. A narrow receiver bandwidth is attained by one of two methods; (a) heterodyne detection or (b) optical filtering. A direct measurement of emissivity is used to adjust the value obtained for the thermal radiation signal to substantially enhance the accuracy of the temperature measurement for a given subject surface. The technique provides substantially high detection sensitivity over a very narrow spectral bandwidth.
Abstract:
A computer-implemented method of forming a thermal-based electronic image of an object that includes receiving electromagnetic radiation emitted by the object at an optically sensitive layer including a superpixel having a plurality of pixels. Each pixel of the plurality of pixels includes a plasmonic absorber having a characteristic resonance wavelength and that generates a radiance measurement of the electromagnetic radiation at its characteristic resonance wavelength. The method further provides for determining, at a processor, an emissivity and temperature for the electromagnetic radiation received at the superpixel using the radiance measurements obtained at the pixels of the superpixel. In addition, the method provides for forming an image of the object from the determined emissivity and temperature.
Abstract:
A Safety Cooking Device includes a thermal sensor that detects infrared radiation (IR) to generate thermal images of a cooktop over time, and a controller. The controller uses the thermal images to determine whether the cooktop is unattended. Both wired and wireless embodiments of the cooking safety device are disclosed. In one implementation, the cooking safety device is in communication with and reports to a security panel of a security system.