A small calibrator has been constructed to facilitate wide-band liquid crystal temperature measurements on complex, curved surfaces. The calibrator’s size, 21.3 mm by 20.3 mm by 10.0 mm thick, makes it ideal for in-situ calibrations at multiple sites on curved surfaces. Its design utilizes the heating/cooling ability of a thermoelectric cooler, and its temperature is quickly and accurately controlled by computer. To test the calibrator’s accuracy, a liquid crystal sample was calibrated. Subsequent comparisons to thermistor measurements of a uniform temperature copper block painted with liquid crystals showed the calibration to be accurate to +/−0.1°C between the red start and the approximate blue start temperatures, and the maximum error was less than +/−0.3°C in the dark blue/violet region.

Issue Section:
Technical Notes
Keywords:
liquid crystals, temperature measurement, calibration
Topics:
Calibration, Liquid crystals, Temperature, Temperature measurement, Copper, Thermoelectric coolers, Design
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 by ASME
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