| 摘要 |
<p>1,233,579. Backscatter thickness gauges. ATOMIC ENERGY OF CANADA Ltd., COMMERCIAL PRODUCTS. Sept.16, 1968 [Nov.14, 1967], No.43890/68. Heading G1A. [Also in Divisions H1 and H3] The thickness of filament material is measured by detecting the degree to which radiation from a radio-active source having an energy in the range 20-60 KeV is scattered by the filament material. Gamma radiation from an I125 source 10 passes through a collimating slit 12 and falls on the filament to be measured. Scattered radiation passes through windows 13 to an ionization chamber, (see Division H1) the output of which is amplified by an FET amplifier (see Division H3) for display on a meter and recorder. The independence of the measurement of the shape and position of the filament, which together with its independence of dyestuffs therein is demonstrated by experimental results, may be improved by locating triangular masks in front of the ionization chamber windows. The disadvantages of other radiation sources such as Sr 90/Y90; Cd 109 and Am 241 are discussed.</p> |
