Liquid crystal is a chemical compound which changes its color with temperature. It is useful in non-intrusively visualizing instantaneous surface temperature changes, where other conventional temperature sensors cannot be used. The thermal field visualization can either be (a) qualitative, by observing the pattern of color change, or (b) quantitative by calibrating it with a thermocouple at a known temperature range. The material is available in the temperature range of -30 degrees C to 115 degrees C. The minimum and average error values associated with the temperature measurement are 0.01 degrees C and 0.5 degrees C, respectively.