Bull. Spec. CORESTA Symposium, Taormina, 1986, p. 99, ST01, ISSN.0525-6240

Assembly and calibration of an infrared thermal imaging system for the study of temperature distributions in cigarette coals

Philip Morris USA, Richmond, VA, USA
There are a number of thermal imaging systems available commercially that will convert the image of a scene or object as it appears in the infrared to a video signal that can be viewed on a television monitor. Since the infrared radiation emitted by an object is related to its temperature, one can, with reasonable care, use such an imaging system to measure temperature. This paper discusses the assembly and calibration of an Inframetrics Model 525 thermal imaging system along with the special adaptations needed for cigarette coal studies. The thermal camera was equipped with an 8-bit microprocessor to produce a grey scale with 256 levels for detailed temperature measurements. A special close-up lens was used to produce a magnified image of the coal. The camera system also included a colorizer which produces false colored images from the original monochrome (black and white) pictures. These false colored images are useful for visualizing the temperature contours. The video equipment used to support the thermal camera included a video tape recorder to store the video images for later analysis, a video timer that placed the date and time on each video frame and several video monitors. In addition, a digital image processor was programmed to relate the recorded infrared images to the temperature distributions in a cigarette coal. The image processing programs will be covered briefly and preliminary results from the computer analysis will be presented.