Abstract: A liquid crystal temperature indicator measures human body temperatures. The temperature indicator comprises a generally planar member for retention against an outer surface of a body. A number of deposits of liquid crystals, each activatable within a predetermined temperature range to be measured, are arranged behind temperature-indicating numerals. At a temperature within the predetermined temperature range, at least one of the deposits emits or reflects visible radiation to make corresponding numerals visible for indicating the surface temperature of the body. However, numerals are calibrated to the corresponding oral temperatures. A non-water soluble lacquer coating protects the deposits from moisture or humidity.

Abstract: An indicator which is suitable for measuring a body temperature has a generally planar member shaped for retention against a very small outer surface of a body. A temperature-sensitive material is visually activatable within a predetermined temperature range. The temperature-sensitive substance emits, reflects or refracts visible radiation to indicate the temperature. The color sequence in normal white light progresses from tan through red, green and blue and ultraviolet on temperature activation, the color red normally being the first easily visible response when the temperature reaches its responsive range. Thereafter, the color falls off and tends to remain a blue color after the temperature moves above the activation range. An optical filter visually blocks out the blue color to limit the response to the active range.