Showing papers on "Thermography published in 1968"

Thermography of Smoking

Abstract: Thermography brings skin temperature recording into the space age. Instead of “loading” the skin by using contact thermometers, such as thermocouples, and obtaining inaccurate temperature readings or a record of an isolated area, thermographs furnish thermal maps of large areas of skin surface without touching the subject. These maps, or thermograms, are made with various types of apparatus. In one thermograph, thousands of point-to-point temperature readings are detected by a sensitive thermistor bolometer in a two-to four-minute scan and registered on photographic film. In another device, a photoconductive sensor assembles the temperature readings rapidly into a pattern on a television screen. The image can be viewed in seconds and can also be photographed for later analysis. About six thermographs are on the market or are being developed. They offer pictorial representations of skin temperatures whose interpretation opens entirely new fields for the study of abnormalities of peripheral vascular circula...

A prism line-scanner for high-speed thermography.

Abstract: Thermographic instruments using single-element line scanning usually have very low line frequencies in comparison with television. To meet the requirements for higher frame rates in thermography and infra-red viewing a line scanner with an indium antimonide detector and a rotating germanium prism has been designed. It produces heat images with 100 lines per frame on a television-type display tube at a flicker-free frame rate. The sweep efficiency of the scanning system is almost 100 per cent. The optical aberrations introduced by the scanning prism are analysed and found to be at a minimum when the refractive index lies between 3 and 4. Examples of heat pictures taken with different modes of operation are given.

Thermography and Osteosarcoma

Abstract: Preliminary studies indicate that thermography is useful in evaluating patients with osteosarcoma. It may be employed to determine local extent and vascularity of the primary tumor, recurrence, and metastases. The thermogram may present findings not immediately detectable by conventional diagnostic methods. Procedure We utilize a high-speed infrared scanning device, the Pyroscan, which gives 40,000 separate temperature measurements in thirty seconds and records on newspaper facsimile paper. These scans measure a temperature range of 6° C with sensitivity of 0.3° C. The polarity is modified so that the warmer areas are recorded darker than the colder areas. The scans are performed in a room in which the temperature is 68° F, and the skin areas to be measured are exposed to this environment for eight minutes prior to thermography. Nineteen patients with osteosarcoma have been evaluated in two and a half years. The involved site was scanned in four positions; anteroposterior, postero-anterior, and both later...