RADIATION-DOSE INDICATOR AS WELL AS A LAMP AND A TANNING APPARATUS COMPRISING SUCH A RADIATION-DOSE INDICATOR

摘要

Radiation-dose indicator as well as a lamp and a tanning apparatus comprising such a radiation-dose indicator. The invention provides a novel type of radiation-dose indicator which is reliable and accurate. The indicator comprises an optically active layer which includes a liquid-crystalline material as well as a radiation-sensitive compound. This compound is converted under the influence of radiation in such a way as to change the order of the liquid-crystalline material. Preferably, a trans-isomer is used as the radiation-sensitive compound, which is converted to the corresponding cis-isomer under the influence of radiation. In this way, the order of the liquid-crystalline material is broken. Indicators in accordance with the invention can very advantageously be used in UV- and IR-lamps as well as in tanning apparatus.