[Problems of photographic documentation of color patterns in connection with the use of thermography with liquid crystals (author's transl)].

Cholesteric liquid crystals show different colors dependent on their temperature. The "thermography with liquid crystals" makes use of this property for the determination of temperature distributions of human skin. The correct photographic documentation of the color patterns is difficult, because the colors depend on the angle of incidence of light and the direction of observation. Further, the quality of the photos is reduced by the direct reflection of light at the surface. Possible geometrical conditions of taking photos are discussed. An optimum arrangement for producing photos without reflections and color changes is proposed.