Sensing elements are located at various required levels in a vacuum dewar. Resistance changes are detected external to the container and used to indicate the presence of a liquid at a particular level. This invention is utilized at present as part of an infrared aircraft detection system. This system has 28 IR detectors arranged in a vertical line and located in a glass dewar. These detectors have to be cooled to 77 K by liquid nitrogen LN2 for proper operation. The detector-dewar assembly is located in the focal plane of a Schmidt optical system. This optical unit is rotated at a 1 revolution/second rate and becomes the scanning head of the infrared aircraft detection system.
Liquid Nitrogen Level Indicator
1978
5 pages
Report
Keine Angabe
Englisch